Unicode 对象和编解码器 ¶

Unicode 类型 ¶

These are the basic Unicode object types used for the Unicode implementation in Python:

Py_UCS4 ¶

Py_UCS2 ¶

Py_UCS1 ¶

These types are typedefs for unsigned integer types wide enough to contain characters of 32 bits, 16 bits and 8 bits, respectively. When dealing with single Unicode characters, use Py_UCS4 .

3.3 版新增。

Py_UNICODE ¶

This is a typedef of wchar_t , which is a 16-bit type or 32-bit type depending on the platform.

3.3 版改变： In previous versions, this was a 16-bit type or a 32-bit type depending on whether you selected a “narrow” or “wide” Unicode version of Python at build time.

PyASCIIObject ¶

PyCompactUnicodeObject ¶

PyUnicodeObject ¶

These subtypes of PyObject represent a Python Unicode object. In almost all cases, they shouldn’t be used directly, since all API functions that deal with Unicode objects take and return PyObject pointers.

3.3 版新增。

PyTypeObject PyUnicode_Type ¶

此实例的 PyTypeObject represents the Python Unicode type. It is exposed to Python code as str .

The following APIs are really C macros and can be used to do fast checks and to access internal read-only data of Unicode objects:

int PyUnicode_Check ( PyObject  *o ) ¶

Return true if the object o is a Unicode object or an instance of a Unicode subtype.

int PyUnicode_CheckExact ( PyObject  *o ) ¶

Return true if the object o is a Unicode object, but not an instance of a subtype.

int PyUnicode_READY ( PyObject  *o ) ¶

Ensure the string object o is in the “canonical” representation. This is required before using any of the access macros described below.

返回 0 on success and -1 with an exception set on failure, which in particular happens if memory allocation fails.

3.3 版新增。

Py_ssize_t PyUnicode_GET_LENGTH ( PyObject  *o ) ¶

Return the length of the Unicode string, in code points. o has to be a Unicode object in the “canonical” representation (not checked).

3.3 版新增。

Py_UCS1 * PyUnicode_1BYTE_DATA ( PyObject  *o ) ¶

Py_UCS2 * PyUnicode_2BYTE_DATA ( PyObject  *o ) ¶

Py_UCS4 * PyUnicode_4BYTE_DATA ( PyObject  *o ) ¶

Return a pointer to the canonical representation cast to UCS1, UCS2 or UCS4 integer types for direct character access. No checks are performed if the canonical representation has the correct character size; use PyUnicode_KIND() to select the right macro. Make sure PyUnicode_READY() has been called before accessing this.

3.3 版新增。

PyUnicode_WCHAR_KIND ¶

PyUnicode_1BYTE_KIND ¶

PyUnicode_2BYTE_KIND ¶

PyUnicode_4BYTE_KIND ¶

Return values of the PyUnicode_KIND() 宏。

3.3 版新增。

int PyUnicode_KIND ( PyObject  *o ) ¶

Return one of the PyUnicode kind constants (see above) that indicate how many bytes per character this Unicode object uses to store its data. o has to be a Unicode object in the “canonical” representation (not checked).

3.3 版新增。

void* PyUnicode_DATA ( PyObject  *o ) ¶

Return a void pointer to the raw unicode buffer. o has to be a Unicode object in the “canonical” representation (not checked).

3.3 版新增。

void PyUnicode_WRITE ( int  kind , void  *data , Py_ssize_t  index , Py_UCS4  value ) ¶

Write into a canonical representation data (as obtained with PyUnicode_DATA() ). This macro does not do any sanity checks and is intended for usage in loops. The caller should cache the kind value and data pointer as obtained from other macro calls. index is the index in the string (starts at 0) and value is the new code point value which should be written to that location.

3.3 版新增。

Py_UCS4 PyUnicode_READ ( int  kind , void  *data , Py_ssize_t  index ) ¶

Read a code point from a canonical representation data (as obtained with PyUnicode_DATA() ). No checks or ready calls are performed.

3.3 版新增。

Py_UCS4 PyUnicode_READ_CHAR ( PyObject  *o , Py_ssize_t  index ) ¶

Read a character from a Unicode object o , which must be in the “canonical” representation. This is less efficient than PyUnicode_READ() if you do multiple consecutive reads.

3.3 版新增。

PyUnicode_MAX_CHAR_VALUE ( PyObject  *o ) ¶

Return the maximum code point that is suitable for creating another string based on o , which must be in the “canonical” representation. This is always an approximation but more efficient than iterating over the string.

3.3 版新增。

int PyUnicode_ClearFreeList ( ) ¶

Clear the free list. Return the total number of freed items.

Py_ssize_t PyUnicode_GET_SIZE ( PyObject  *o ) ¶

Return the size of the deprecated Py_UNICODE representation, in code units (this includes surrogate pairs as 2 units). o has to be a Unicode object (not checked).

Deprecated since version 3.3, will be removed in version 4.0: Part of the old-style Unicode API, please migrate to using PyUnicode_GET_LENGTH() .

Py_ssize_t PyUnicode_GET_DATA_SIZE ( PyObject  *o ) ¶

Return the size of the deprecated Py_UNICODE representation in bytes. o has to be a Unicode object (not checked).

Deprecated since version 3.3, will be removed in version 4.0: Part of the old-style Unicode API, please migrate to using PyUnicode_GET_LENGTH() .

Py_UNICODE * PyUnicode_AS_UNICODE ( PyObject  *o ) ¶

const char* PyUnicode_AS_DATA ( PyObject  *o ) ¶

Return a pointer to a Py_UNICODE representation of the object. The returned buffer is always terminated with an extra null code point. It may also contain embedded null code points, which would cause the string to be truncated when used in most C functions. The AS_DATA form casts the pointer to const char * 。 o argument has to be a Unicode object (not checked).

3.3 版改变： This macro is now inefficient – because in many cases the Py_UNICODE representation does not exist and needs to be created – and can fail (return NULL with an exception set). Try to port the code to use the new PyUnicode_nBYTE_DATA() macros or use PyUnicode_WRITE() or PyUnicode_READ() .

Deprecated since version 3.3, will be removed in version 4.0: Part of the old-style Unicode API, please migrate to using the PyUnicode_nBYTE_DATA() family of macros.

Unicode 字符特性 ¶

Unicode provides many different character properties. The most often needed ones are available through these macros which are mapped to C functions depending on the Python configuration.

int Py_UNICODE_ISSPACE ( Py_UNICODE  ch ) ¶

返回 1 or 0 depending on whether ch is a whitespace character.

int Py_UNICODE_ISLOWER ( Py_UNICODE  ch ) ¶

返回 1 or 0 depending on whether ch is a lowercase character.

int Py_UNICODE_ISUPPER ( Py_UNICODE  ch ) ¶

返回 1 or 0 depending on whether ch is an uppercase character.

int Py_UNICODE_ISTITLE ( Py_UNICODE  ch ) ¶

返回 1 or 0 depending on whether ch is a titlecase character.

int Py_UNICODE_ISLINEBREAK ( Py_UNICODE  ch ) ¶

返回 1 or 0 depending on whether ch is a linebreak character.

int Py_UNICODE_ISDECIMAL ( Py_UNICODE  ch ) ¶

返回 1 or 0 depending on whether ch is a decimal character.

int Py_UNICODE_ISDIGIT ( Py_UNICODE  ch ) ¶

返回 1 or 0 depending on whether ch is a digit character.

int Py_UNICODE_ISNUMERIC ( Py_UNICODE  ch ) ¶

返回 1 or 0 depending on whether ch is a numeric character.

int Py_UNICODE_ISALPHA ( Py_UNICODE  ch ) ¶

返回 1 or 0 depending on whether ch is an alphabetic character.

int Py_UNICODE_ISALNUM ( Py_UNICODE  ch ) ¶

返回 1 or 0 depending on whether ch is an alphanumeric character.

int Py_UNICODE_ISPRINTABLE ( Py_UNICODE  ch ) ¶

返回 1 or 0 depending on whether ch is a printable character. Nonprintable characters are those characters defined in the Unicode character database as “Other” or “Separator”, excepting the ASCII space (0x20) which is considered printable. (Note that printable characters in this context are those which should not be escaped when repr() is invoked on a string. It has no bearing on the handling of strings written to sys.stdout or sys.stderr .)

These APIs can be used for fast direct character conversions:

Py_UNICODE Py_UNICODE_TOLOWER ( Py_UNICODE  ch ) ¶

Return the character ch converted to lower case.

从 3.3 版起弃用： This function uses simple case mappings.

Py_UNICODE Py_UNICODE_TOUPPER ( Py_UNICODE  ch ) ¶

Return the character ch converted to upper case.

从 3.3 版起弃用： This function uses simple case mappings.

Py_UNICODE Py_UNICODE_TOTITLE ( Py_UNICODE  ch ) ¶

Return the character ch converted to title case.

从 3.3 版起弃用： This function uses simple case mappings.

int Py_UNICODE_TODECIMAL ( Py_UNICODE  ch ) ¶

Return the character ch converted to a decimal positive integer. Return -1 if this is not possible. This macro does not raise exceptions.

int Py_UNICODE_TODIGIT ( Py_UNICODE  ch ) ¶

Return the character ch converted to a single digit integer. Return -1 if this is not possible. This macro does not raise exceptions.

double Py_UNICODE_TONUMERIC ( Py_UNICODE  ch ) ¶

Return the character ch converted to a double. Return -1.0 if this is not possible. This macro does not raise exceptions.

These APIs can be used to work with surrogates:

Py_UNICODE_IS_SURROGATE ( ch ) ¶

Check if ch is a surrogate ( 0xD800 <= ch <= 0xDFFF ).

Py_UNICODE_IS_HIGH_SURROGATE ( ch ) ¶

Check if ch is a high surrogate ( 0xD800 <= ch <= 0xDBFF ).

Py_UNICODE_IS_LOW_SURROGATE ( ch ) ¶

Check if ch is a low surrogate ( 0xDC00 <= ch <= 0xDFFF ).

Py_UNICODE_JOIN_SURROGATES ( high, low ) ¶

Join two surrogate characters and return a single Py_UCS4 value. high and low are respectively the leading and trailing surrogates in a surrogate pair.

创建和访问 Unicode 字符串 ¶

To create Unicode objects and access their basic sequence properties, use these APIs:

PyObject * PyUnicode_New ( Py_ssize_t  size , Py_UCS4  maxchar ) ¶

Create a new Unicode object. maxchar should be the true maximum code point to be placed in the string. As an approximation, it can be rounded up to the nearest value in the sequence 127, 255, 65535, 1114111.

This is the recommended way to allocate a new Unicode object. Objects created using this function are not resizable.

3.3 版新增。

PyObject * PyUnicode_FromKindAndData ( int  kind , const void  *buffer , Py_ssize_t  size ) ¶

Create a new Unicode object with the given kind (possible values are PyUnicode_1BYTE_KIND etc., as returned by PyUnicode_KIND() )。 buffer must point to an array of size units of 1, 2 or 4 bytes per character, as given by the kind.

3.3 版新增。

PyObject * PyUnicode_FromStringAndSize ( const char  *u , Py_ssize_t  size ) ¶

Create a Unicode object from the char buffer u . The bytes will be interpreted as being UTF-8 encoded. The buffer is copied into the new object. If the buffer is not NULL , the return value might be a shared object, i.e. modification of the data is not allowed.

若 u is NULL , this function behaves like PyUnicode_FromUnicode() with the buffer set to NULL . This usage is deprecated in favor of PyUnicode_New() .

PyObject * PyUnicode_FromString ( const char  *u ) ¶

Create a Unicode object from a UTF-8 encoded null-terminated char buffer u .

PyObject * PyUnicode_FromFormat ( const char  *format , ... ) ¶

Take a C printf() -style format string and a variable number of arguments, calculate the size of the resulting Python unicode string and return a string with the values formatted into it. The variable arguments must be C types and must correspond exactly to the format characters in the format ASCII-encoded string. The following format characters are allowed:

格式字符	类型	Comment
%%	n/a	The literal % character.
%c	int	A single character, represented as a C int.
%d	int	Exactly equivalent to printf("%d") .
%u	无符号 int	Exactly equivalent to printf("%u") .
%ld	long	Exactly equivalent to printf("%ld") .
%li	long	Exactly equivalent to printf("%li") .
%lu	unsigned long	Exactly equivalent to printf("%lu") .
%lld	long long	Exactly equivalent to printf("%lld") .
%lli	long long	Exactly equivalent to printf("%lli") .
%llu	unsigned long long	Exactly equivalent to printf("%llu") .
%zd	Py_ssize_t	Exactly equivalent to printf("%zd") .
%zi	Py_ssize_t	Exactly equivalent to printf("%zi") .
%zu	size_t	Exactly equivalent to printf("%zu") .
%i	int	Exactly equivalent to printf("%i") .
%x	int	Exactly equivalent to printf("%x") .
%s	char*	A null-terminated C character array.
%p	void*	The hex representation of a C pointer. Mostly equivalent to printf("%p") except that it is guaranteed to start with the literal 0x regardless of what the platform’s printf yields.
%A	PyObject*	The result of calling ascii() .
%U	PyObject*	A unicode object.
%V	PyObject*, char *	A unicode object (which may be NULL ) and a null-terminated C character array as a second parameter (which will be used, if the first parameter is NULL ).
%S	PyObject*	The result of calling PyObject_Str() .
%R	PyObject*	The result of calling PyObject_Repr() .

An unrecognized format character causes all the rest of the format string to be copied as-is to the result string, and any extra arguments discarded.

注意

The width formatter unit is number of characters rather than bytes. The precision formatter unit is number of bytes for "%s" and "%V" (if the PyObject* argument is NULL), and a number of characters for "%A" , "%U" , "%S" , "%R" and "%V" (if the PyObject* argument is not NULL).

3.2 版改变： 支持 "%lld" and "%llu" added.

3.3 版改变： 支持 "%li" , "%lli" and "%zi" added.

3.4 版改变： Support width and precision formatter for "%s" , "%A" , "%U" , "%V" , "%S" , "%R" added.

PyObject * PyUnicode_FromFormatV ( const char  *format , va_list  vargs ) ¶

等同于 PyUnicode_FromFormat() except that it takes exactly two arguments.

PyObject * PyUnicode_FromEncodedObject ( PyObject  *obj , const char  *encoding , const char  *errors ) ¶

返回值：新引用。

Decode an encoded object obj to a Unicode object.

bytes , bytearray and other 像字节对象 are decoded according to the given encoding and using the error handling defined by errors . Both can be NULL to have the interface use the default values (see 内置编解码器 了解细节)。

All other objects, including Unicode objects, cause a TypeError to be set.

The API returns NULL if there was an error. The caller is responsible for decref’ing the returned objects.

Py_ssize_t PyUnicode_GetLength ( PyObject  *unicode ) ¶

Return the length of the Unicode object, in code points.

3.3 版新增。

Py_ssize_t PyUnicode_CopyCharacters ( PyObject  *to , Py_ssize_t  to_start , PyObject  *from , Py_ssize_t  from_start , Py_ssize_t  how_many ) ¶

Copy characters from one Unicode object into another. This function performs character conversion when necessary and falls back to memcpy() if possible. Returns -1 and sets an exception on error, otherwise returns the number of copied characters.

3.3 版新增。

Py_ssize_t PyUnicode_Fill ( PyObject  *unicode , Py_ssize_t  start , Py_ssize_t  length , Py_UCS4  fill_char ) ¶

Fill a string with a character: write fill_char into unicode[start:start+length] .

Fail if fill_char is bigger than the string maximum character, or if the string has more than 1 reference.

Return the number of written character, or return -1 and raise an exception on error.

3.3 版新增。

int PyUnicode_WriteChar ( PyObject  *unicode , Py_ssize_t  index , Py_UCS4  character ) ¶

Write a character to a string. The string must have been created through PyUnicode_New() . Since Unicode strings are supposed to be immutable, the string must not be shared, or have been hashed yet.

This function checks that unicode is a Unicode object, that the index is not out of bounds, and that the object can be modified safely (i.e. that it its reference count is one).

3.3 版新增。

Py_UCS4 PyUnicode_ReadChar ( PyObject  *unicode , Py_ssize_t  index ) ¶

Read a character from a string. This function checks that unicode is a Unicode object and the index is not out of bounds, in contrast to the macro version PyUnicode_READ_CHAR() .

3.3 版新增。

PyObject * PyUnicode_Substring ( PyObject  *str , Py_ssize_t  start , Py_ssize_t  end ) ¶

Return a substring of str , from character index start (included) to character index end (excluded). Negative indices are not supported.

3.3 版新增。

Py_UCS4 * PyUnicode_AsUCS4 ( PyObject  *u , Py_UCS4  *buffer , Py_ssize_t  buflen , int  copy_null ) ¶

Copy the string u into a UCS4 buffer, including a null character, if copy_null is set. Returns NULL and sets an exception on error (in particular, a SystemError if buflen is smaller than the length of u ). buffer 被返回当成功时。

3.3 版新增。

Py_UCS4 * PyUnicode_AsUCS4Copy ( PyObject  *u ) ¶

Copy the string u into a new UCS4 buffer that is allocated using PyMem_Malloc() . If this fails, NULL is returned with a MemoryError set. The returned buffer always has an extra null code point appended.

3.3 版新增。

弃用 Py_UNICODE API ¶

These API functions are deprecated with the implementation of PEP 393 . Extension modules can continue using them, as they will not be removed in Python 3.x, but need to be aware that their use can now cause performance and memory hits.

PyObject * PyUnicode_FromUnicode ( const Py_UNICODE  *u , Py_ssize_t  size ) ¶

返回值：新引用。

Create a Unicode object from the Py_UNICODE buffer u of the given size. u 可以是 NULL which causes the contents to be undefined. It is the user’s responsibility to fill in the needed data. The buffer is copied into the new object.

If the buffer is not NULL , the return value might be a shared object. Therefore, modification of the resulting Unicode object is only allowed when u is NULL .

If the buffer is NULL , PyUnicode_READY() must be called once the string content has been filled before using any of the access macros such as PyUnicode_KIND() .

Please migrate to using PyUnicode_FromKindAndData() , PyUnicode_FromWideChar() or PyUnicode_New() .

Py_UNICODE * PyUnicode_AsUnicode ( PyObject  *unicode ) ¶

Return a read-only pointer to the Unicode object’s internal Py_UNICODE buffer, or NULL on error. This will create the Py_UNICODE* representation of the object if it is not yet available. The buffer is always terminated with an extra null code point. Note that the resulting Py_UNICODE string may also contain embedded null code points, which would cause the string to be truncated when used in most C functions.

Please migrate to using PyUnicode_AsUCS4() , PyUnicode_AsWideChar() , PyUnicode_ReadChar() or similar new APIs.

PyObject * PyUnicode_TransformDecimalToASCII ( Py_UNICODE  *s , Py_ssize_t  size ) ¶

Create a Unicode object by replacing all decimal digits in Py_UNICODE buffer of the given size by ASCII digits 0–9 according to their decimal value. Return NULL if an exception occurs.

Py_UNICODE * PyUnicode_AsUnicodeAndSize ( PyObject  *unicode , Py_ssize_t  *size ) ¶

像 PyUnicode_AsUnicode() , but also saves the Py_UNICODE() array length (excluding the extra null terminator) in size . Note that the resulting Py_UNICODE* string may contain embedded null code points, which would cause the string to be truncated when used in most C functions.

3.3 版新增。

Py_UNICODE * PyUnicode_AsUnicodeCopy ( PyObject  *unicode ) ¶

Create a copy of a Unicode string ending with a null code point. Return NULL and raise a MemoryError exception on memory allocation failure, otherwise return a new allocated buffer (use PyMem_Free() to free the buffer). Note that the resulting Py_UNICODE* string may contain embedded null code points, which would cause the string to be truncated when used in most C functions.

3.2 版新增。

Please migrate to using PyUnicode_AsUCS4Copy() or similar new APIs.

Py_ssize_t PyUnicode_GetSize ( PyObject  *unicode ) ¶

Return the size of the deprecated Py_UNICODE representation, in code units (this includes surrogate pairs as 2 units).

Please migrate to using PyUnicode_GetLength() .

PyObject * PyUnicode_FromObject ( PyObject  *obj ) ¶

返回值：新引用。

Copy an instance of a Unicode subtype to a new true Unicode object if necessary. If obj is already a true Unicode object (not a subtype), return the reference with incremented refcount.

Objects other than Unicode or its subtypes will cause a TypeError .

区域设置编码 ¶

The current locale encoding can be used to decode text from the operating system.

PyObject * PyUnicode_DecodeLocaleAndSize ( const char  *str , Py_ssize_t  len , const char  *errors ) ¶

Decode a string from the current locale encoding. The supported error handlers are "strict" and "surrogateescape" ( PEP 383 ). The decoder uses "strict" error handler if errors is NULL . str must end with a null character but cannot contain embedded null characters.

使用 PyUnicode_DecodeFSDefaultAndSize() to decode a string from Py_FileSystemDefaultEncoding (the locale encoding read at Python startup).

另请参阅

Py_DecodeLocale() 函数。

3.3 版新增。

3.6.5 版改变： The function now also uses the current locale encoding for the surrogateescape error handler. Previously, Py_DecodeLocale() was used for the surrogateescape , and the current locale encoding was used for strict .

PyObject * PyUnicode_DecodeLocale ( const char  *str , const char  *errors ) ¶

类似 PyUnicode_DecodeLocaleAndSize() , but compute the string length using strlen() .

3.3 版新增。

PyObject * PyUnicode_EncodeLocale ( PyObject  *unicode , const char  *errors ) ¶

Encode a Unicode object to the current locale encoding. The supported error handlers are "strict" and "surrogateescape" ( PEP 383 ). The encoder uses "strict" error handler if errors is NULL 。返回 bytes 对象。 unicode cannot contain embedded null characters.

使用 PyUnicode_EncodeFSDefault() to encode a string to Py_FileSystemDefaultEncoding (the locale encoding read at Python startup).

另请参阅

Py_EncodeLocale() 函数。

3.3 版新增。

3.6.5 版改变： The function now also uses the current locale encoding for the surrogateescape error handler. Previously, Py_EncodeLocale() was used for the surrogateescape , and the current locale encoding was used for strict .

文件系统编码 ¶

To encode and decode file names and other environment strings, Py_FileSystemDefaultEncoding should be used as the encoding, and Py_FileSystemDefaultEncodeErrors should be used as the error handler ( PEP 383 and PEP 529 ). To encode file names to bytes during argument parsing, the "O&" converter should be used, passing PyUnicode_FSConverter() as the conversion function:

int PyUnicode_FSConverter ( PyObject *  obj , void*  result ) ¶

ParseTuple converter: encode str objects – obtained directly or through the os.PathLike interface – to bytes 使用 PyUnicode_EncodeFSDefault() ; bytes objects are output as-is. result 必须是 PyBytesObject* which must be released when it is no longer used.

3.1 版新增。

3.6 版改变： 接受 像路径对象 .

To decode file names to str during argument parsing, the "O&" converter should be used, passing PyUnicode_FSDecoder() as the conversion function:

int PyUnicode_FSDecoder ( PyObject *  obj , void*  result ) ¶

ParseTuple converter: decode bytes objects – obtained either directly or indirectly through the os.PathLike interface – to str 使用 PyUnicode_DecodeFSDefaultAndSize() ; str objects are output as-is. result 必须是 PyUnicodeObject* which must be released when it is no longer used.

3.2 版新增。

3.6 版改变： 接受 像路径对象 .

PyObject * PyUnicode_DecodeFSDefaultAndSize ( const char  *s , Py_ssize_t  size ) ¶

Decode a string using Py_FileSystemDefaultEncoding 和 Py_FileSystemDefaultEncodeErrors 错误处理程序。

若 Py_FileSystemDefaultEncoding is not set, fall back to the locale encoding.

Py_FileSystemDefaultEncoding is initialized at startup from the locale encoding and cannot be modified later. If you need to decode a string from the current locale encoding, use PyUnicode_DecodeLocaleAndSize() .

另请参阅

Py_DecodeLocale() 函数。

3.6 版改变： 使用 Py_FileSystemDefaultEncodeErrors 错误处理程序。

PyObject * PyUnicode_DecodeFSDefault ( const char  *s ) ¶

Decode a null-terminated string using Py_FileSystemDefaultEncoding 和 Py_FileSystemDefaultEncodeErrors 错误处理程序。

若 Py_FileSystemDefaultEncoding is not set, fall back to the locale encoding.

使用 PyUnicode_DecodeFSDefaultAndSize() if you know the string length.

3.6 版改变： 使用 Py_FileSystemDefaultEncodeErrors 错误处理程序。

PyObject * PyUnicode_EncodeFSDefault ( PyObject  *unicode ) ¶

Encode a Unicode object to Py_FileSystemDefaultEncoding 采用 Py_FileSystemDefaultEncodeErrors error handler, and return bytes . Note that the resulting bytes object may contain null bytes.

若 Py_FileSystemDefaultEncoding is not set, fall back to the locale encoding.

Py_FileSystemDefaultEncoding is initialized at startup from the locale encoding and cannot be modified later. If you need to encode a string to the current locale encoding, use PyUnicode_EncodeLocale() .

另请参阅

Py_EncodeLocale() 函数。

3.2 版新增。

3.6 版改变： 使用 Py_FileSystemDefaultEncodeErrors 错误处理程序。

wchar_t 支持 ¶

wchar_t support for platforms which support it:

PyObject * PyUnicode_FromWideChar ( const wchar_t  *w , Py_ssize_t  size ) ¶

返回值：新引用。

Create a Unicode object from the wchar_t buffer w of the given size . Passing -1 作为 size indicates that the function must itself compute the length, using wcslen. Return NULL 当故障时。

Py_ssize_t PyUnicode_AsWideChar ( PyObject  *unicode , wchar_t  *w , Py_ssize_t  size ) ¶

Copy the Unicode object contents into the wchar_t buffer w . At most size wchar_t characters are copied (excluding a possibly trailing null termination character). Return the number of wchar_t characters copied or -1 in case of an error. Note that the resulting wchar_t* string may or may not be null-terminated. It is the responsibility of the caller to make sure that the wchar_t* string is null-terminated in case this is required by the application. Also, note that the wchar_t* string might contain null characters, which would cause the string to be truncated when used with most C functions.

wchar_t* PyUnicode_AsWideCharString ( PyObject  *unicode , Py_ssize_t  *size ) ¶

Convert the Unicode object to a wide character string. The output string always ends with a null character. If size 不是 NULL , write the number of wide characters (excluding the trailing null termination character) into *size .

Returns a buffer allocated by PyMem_Alloc() (use PyMem_Free() to free it) on success. On error, returns NULL , *size is undefined and raises a MemoryError . Note that the resulting wchar_t string might contain null characters, which would cause the string to be truncated when used with most C functions.

3.2 版新增。

一般编解码器 ¶

These are the generic codec APIs:

PyObject * PyUnicode_Decode ( const char  *s , Py_ssize_t  size , const char  *encoding , const char  *errors ) ¶

返回值：新引用。

Create a Unicode object by decoding size bytes of the encoded string s . encoding and errors have the same meaning as the parameters of the same name in the str() built-in function. The codec to be used is looked up using the Python codec registry. Return NULL if an exception was raised by the codec.

PyObject * PyUnicode_AsEncodedString ( PyObject  *unicode , const char  *encoding , const char  *errors ) ¶

返回值：新引用。

Encode a Unicode object and return the result as Python bytes object. encoding and errors have the same meaning as the parameters of the same name in the Unicode encode() method. The codec to be used is looked up using the Python codec registry. Return NULL if an exception was raised by the codec.

PyObject * PyUnicode_Encode ( const Py_UNICODE  *s , Py_ssize_t  size , const char  *encoding , const char  *errors ) ¶

返回值：新引用。

编码 Py_UNICODE buffer s of the given size and return a Python bytes object. encoding and errors have the same meaning as the parameters of the same name in the Unicode encode() method. The codec to be used is looked up using the Python codec registry. Return NULL if an exception was raised by the codec.

Deprecated since version 3.3, will be removed in version 4.0: Part of the old-style Py_UNICODE API；请迁移到使用 PyUnicode_AsEncodedString() .

UTF-8 编解码器 ¶

These are the UTF-8 codec APIs:

PyObject * PyUnicode_DecodeUTF8 ( const char  *s , Py_ssize_t  size , const char  *errors ) ¶

返回值：新引用。

Create a Unicode object by decoding size bytes of the UTF-8 encoded string s 。返回 NULL if an exception was raised by the codec.

PyObject * PyUnicode_DecodeUTF8Stateful ( const char  *s , Py_ssize_t  size , const char  *errors , Py_ssize_t  *consumed ) ¶

返回值：新引用。

若 consumed is NULL , behave like PyUnicode_DecodeUTF8() 。若 consumed 不是 NULL , trailing incomplete UTF-8 byte sequences will not be treated as an error. Those bytes will not be decoded and the number of bytes that have been decoded will be stored in consumed .

PyObject * PyUnicode_AsUTF8String ( PyObject  *unicode ) ¶

返回值：新引用。

Encode a Unicode object using UTF-8 and return the result as Python bytes object. Error handling is “strict”. Return NULL if an exception was raised by the codec.

char* PyUnicode_AsUTF8AndSize ( PyObject  *unicode , Py_ssize_t  *size ) ¶

Return a pointer to the UTF-8 encoding of the Unicode object, and store the size of the encoded representation (in bytes) in size 。 size argument can be NULL ; in this case no size will be stored. The returned buffer always has an extra null byte appended (not included in size ), regardless of whether there are any other null code points.

In the case of an error, NULL is returned with an exception set and no size 是存储。

This caches the UTF-8 representation of the string in the Unicode object, and subsequent calls will return a pointer to the same buffer. The caller is not responsible for deallocating the buffer.

3.3 版新增。

char* PyUnicode_AsUTF8 ( PyObject  *unicode ) ¶

As PyUnicode_AsUTF8AndSize() , but does not store the size.

3.3 版新增。

PyObject * PyUnicode_EncodeUTF8 ( const Py_UNICODE  *s , Py_ssize_t  size , const char  *errors ) ¶

返回值：新引用。

编码 Py_UNICODE buffer s of the given size using UTF-8 and return a Python bytes object. Return NULL if an exception was raised by the codec.

Deprecated since version 3.3, will be removed in version 4.0: Part of the old-style Py_UNICODE API；请迁移到使用 PyUnicode_AsUTF8String() , PyUnicode_AsUTF8AndSize() or PyUnicode_AsEncodedString() .

UTF-32 编解码器 ¶

These are the UTF-32 codec APIs:

PyObject * PyUnicode_DecodeUTF32 ( const char  *s , Py_ssize_t  size , const char  *errors , int  *byteorder ) ¶

解码 size bytes from a UTF-32 encoded buffer string and return the corresponding Unicode object. errors (if non- NULL ) defines the error handling. It defaults to “strict”.

若 byteorder 为非 NULL , the decoder starts decoding using the given byte order:

*byteorder == -1: little endian
*byteorder == 0:  native order
*byteorder == 1:  big endian
											

若 *byteorder is zero, and the first four bytes of the input data are a byte order mark (BOM), the decoder switches to this byte order and the BOM is not copied into the resulting Unicode string. If *byteorder is -1 or 1 , any byte order mark is copied to the output.

After completion, *byteorder is set to the current byte order at the end of input data.

若 byteorder is NULL , the codec starts in native order mode.

返回 NULL if an exception was raised by the codec.

PyObject * PyUnicode_DecodeUTF32Stateful ( const char  *s , Py_ssize_t  size , const char  *errors , int  *byteorder , Py_ssize_t  *consumed ) ¶

若 consumed is NULL , behave like PyUnicode_DecodeUTF32() 。若 consumed 不是 NULL , PyUnicode_DecodeUTF32Stateful() will not treat trailing incomplete UTF-32 byte sequences (such as a number of bytes not divisible by four) as an error. Those bytes will not be decoded and the number of bytes that have been decoded will be stored in consumed .

PyObject * PyUnicode_AsUTF32String ( PyObject  *unicode ) ¶

Return a Python byte string using the UTF-32 encoding in native byte order. The string always starts with a BOM mark. Error handling is “strict”. Return NULL if an exception was raised by the codec.

PyObject * PyUnicode_EncodeUTF32 ( const Py_UNICODE  *s , Py_ssize_t  size , const char  *errors , int  byteorder ) ¶

Return a Python bytes object holding the UTF-32 encoded value of the Unicode data in s . Output is written according to the following byte order:

byteorder == -1: little endian
byteorder == 0:  native byte order (writes a BOM mark)
byteorder == 1:  big endian
											

If byteorder is 0 , the output string will always start with the Unicode BOM mark (U+FEFF). In the other two modes, no BOM mark is prepended.

若 Py_UNICODE_WIDE is not defined, surrogate pairs will be output as a single code point.

返回 NULL if an exception was raised by the codec.

Deprecated since version 3.3, will be removed in version 4.0: Part of the old-style Py_UNICODE API；请迁移到使用 PyUnicode_AsUTF32String() or PyUnicode_AsEncodedString() .

UTF-16 编解码器 ¶

These are the UTF-16 codec APIs:

PyObject * PyUnicode_DecodeUTF16 ( const char  *s , Py_ssize_t  size , const char  *errors , int  *byteorder ) ¶

返回值：新引用。

解码 size bytes from a UTF-16 encoded buffer string and return the corresponding Unicode object. errors (if non- NULL ) defines the error handling. It defaults to “strict”.

若 byteorder 为非 NULL , the decoder starts decoding using the given byte order:

*byteorder == -1: little endian
*byteorder == 0:  native order
*byteorder == 1:  big endian
											

若 *byteorder is zero, and the first two bytes of the input data are a byte order mark (BOM), the decoder switches to this byte order and the BOM is not copied into the resulting Unicode string. If *byteorder is -1 or 1 , any byte order mark is copied to the output (where it will result in either a \ufeff 或 \ufffe character).

After completion, *byteorder is set to the current byte order at the end of input data.

若 byteorder is NULL , the codec starts in native order mode.

返回 NULL if an exception was raised by the codec.

PyObject * PyUnicode_DecodeUTF16Stateful ( const char  *s , Py_ssize_t  size , const char  *errors , int  *byteorder , Py_ssize_t  *consumed ) ¶

返回值：新引用。

若 consumed is NULL , behave like PyUnicode_DecodeUTF16() 。若 consumed 不是 NULL , PyUnicode_DecodeUTF16Stateful() will not treat trailing incomplete UTF-16 byte sequences (such as an odd number of bytes or a split surrogate pair) as an error. Those bytes will not be decoded and the number of bytes that have been decoded will be stored in consumed .

PyObject * PyUnicode_AsUTF16String ( PyObject  *unicode ) ¶

返回值：新引用。

Return a Python byte string using the UTF-16 encoding in native byte order. The string always starts with a BOM mark. Error handling is “strict”. Return NULL if an exception was raised by the codec.

PyObject * PyUnicode_EncodeUTF16 ( const Py_UNICODE  *s , Py_ssize_t  size , const char  *errors , int  byteorder ) ¶

返回值：新引用。

Return a Python bytes object holding the UTF-16 encoded value of the Unicode data in s . Output is written according to the following byte order:

byteorder == -1: little endian
byteorder == 0:  native byte order (writes a BOM mark)
byteorder == 1:  big endian
											

If byteorder is 0 , the output string will always start with the Unicode BOM mark (U+FEFF). In the other two modes, no BOM mark is prepended.

若 Py_UNICODE_WIDE is defined, a single Py_UNICODE value may get represented as a surrogate pair. If it is not defined, each Py_UNICODE values is interpreted as a UCS-2 character.

返回 NULL if an exception was raised by the codec.

Deprecated since version 3.3, will be removed in version 4.0: Part of the old-style Py_UNICODE API；请迁移到使用 PyUnicode_AsUTF16String() or PyUnicode_AsEncodedString() .

UTF-7 编解码器 ¶

These are the UTF-7 codec APIs:

PyObject * PyUnicode_DecodeUTF7 ( const char  *s , Py_ssize_t  size , const char  *errors ) ¶

Create a Unicode object by decoding size bytes of the UTF-7 encoded string s 。返回 NULL if an exception was raised by the codec.

PyObject * PyUnicode_DecodeUTF7Stateful ( const char  *s , Py_ssize_t  size , const char  *errors , Py_ssize_t  *consumed ) ¶

若 consumed is NULL , behave like PyUnicode_DecodeUTF7() 。若 consumed 不是 NULL , trailing incomplete UTF-7 base-64 sections will not be treated as an error. Those bytes will not be decoded and the number of bytes that have been decoded will be stored in consumed .

PyObject * PyUnicode_EncodeUTF7 ( const Py_UNICODE  *s , Py_ssize_t  size , int  base64SetO , int  base64WhiteSpace , const char  *errors ) ¶

编码 Py_UNICODE buffer of the given size using UTF-7 and return a Python bytes object. Return NULL if an exception was raised by the codec.

若 base64SetO is nonzero, “Set O” (punctuation that has no otherwise special meaning) will be encoded in base-64. If base64WhiteSpace is nonzero, whitespace will be encoded in base-64. Both are set to zero for the Python “utf-7” codec.

Deprecated since version 3.3, will be removed in version 4.0: Part of the old-style Py_UNICODE API；请迁移到使用 PyUnicode_AsEncodedString() .

Unicode 转义编解码器 ¶

These are the “Unicode Escape” codec APIs:

PyObject * PyUnicode_DecodeUnicodeEscape ( const char  *s , Py_ssize_t  size , const char  *errors ) ¶

返回值：新引用。

Create a Unicode object by decoding size bytes of the Unicode-Escape encoded string s 。返回 NULL if an exception was raised by the codec.

PyObject * PyUnicode_AsUnicodeEscapeString ( PyObject  *unicode ) ¶

返回值：新引用。

Encode a Unicode object using Unicode-Escape and return the result as a bytes object. Error handling is “strict”. Return NULL if an exception was raised by the codec.

PyObject * PyUnicode_EncodeUnicodeEscape ( const Py_UNICODE  *s , Py_ssize_t  size ) ¶

返回值：新引用。

编码 Py_UNICODE buffer of the given size using Unicode-Escape and return a bytes object. Return NULL if an exception was raised by the codec.

Deprecated since version 3.3, will be removed in version 4.0: Part of the old-style Py_UNICODE API；请迁移到使用 PyUnicode_AsUnicodeEscapeString() .

原生 Unicode 转义编解码器 ¶

These are the “Raw Unicode Escape” codec APIs:

PyObject * PyUnicode_DecodeRawUnicodeEscape ( const char  *s , Py_ssize_t  size , const char  *errors ) ¶

返回值：新引用。

Create a Unicode object by decoding size bytes of the Raw-Unicode-Escape encoded string s 。返回 NULL if an exception was raised by the codec.

PyObject * PyUnicode_AsRawUnicodeEscapeString ( PyObject  *unicode ) ¶

返回值：新引用。

Encode a Unicode object using Raw-Unicode-Escape and return the result as a bytes object. Error handling is “strict”. Return NULL if an exception was raised by the codec.

PyObject * PyUnicode_EncodeRawUnicodeEscape ( const Py_UNICODE  *s , Py_ssize_t  size ) ¶

返回值：新引用。

编码 Py_UNICODE buffer of the given size using Raw-Unicode-Escape and return a bytes object. Return NULL if an exception was raised by the codec.

Deprecated since version 3.3, will be removed in version 4.0: Part of the old-style Py_UNICODE API；请迁移到使用 PyUnicode_AsRawUnicodeEscapeString() or PyUnicode_AsEncodedString() .

Latin-1 编解码器 ¶

These are the Latin-1 codec APIs: Latin-1 corresponds to the first 256 Unicode ordinals and only these are accepted by the codecs during encoding.

PyObject * PyUnicode_DecodeLatin1 ( const char  *s , Py_ssize_t  size , const char  *errors ) ¶

返回值：新引用。

Create a Unicode object by decoding size bytes of the Latin-1 encoded string s 。返回 NULL if an exception was raised by the codec.

PyObject * PyUnicode_AsLatin1String ( PyObject  *unicode ) ¶

返回值：新引用。

Encode a Unicode object using Latin-1 and return the result as Python bytes object. Error handling is “strict”. Return NULL if an exception was raised by the codec.

PyObject * PyUnicode_EncodeLatin1 ( const Py_UNICODE  *s , Py_ssize_t  size , const char  *errors ) ¶

返回值：新引用。

编码 Py_UNICODE buffer of the given size using Latin-1 and return a Python bytes object. Return NULL if an exception was raised by the codec.

Deprecated since version 3.3, will be removed in version 4.0: Part of the old-style Py_UNICODE API；请迁移到使用 PyUnicode_AsLatin1String() or PyUnicode_AsEncodedString() .

ASCII 编解码器 ¶

These are the ASCII codec APIs. Only 7-bit ASCII data is accepted. All other codes generate errors.

PyObject * PyUnicode_DecodeASCII ( const char  *s , Py_ssize_t  size , const char  *errors ) ¶

返回值：新引用。

Create a Unicode object by decoding size bytes of the ASCII encoded string s 。返回 NULL if an exception was raised by the codec.

PyObject * PyUnicode_AsASCIIString ( PyObject  *unicode ) ¶

返回值：新引用。

Encode a Unicode object using ASCII and return the result as Python bytes object. Error handling is “strict”. Return NULL if an exception was raised by the codec.

PyObject * PyUnicode_EncodeASCII ( const Py_UNICODE  *s , Py_ssize_t  size , const char  *errors ) ¶

返回值：新引用。

编码 Py_UNICODE buffer of the given size using ASCII and return a Python bytes object. Return NULL if an exception was raised by the codec.

Deprecated since version 3.3, will be removed in version 4.0: Part of the old-style Py_UNICODE API；请迁移到使用 PyUnicode_AsASCIIString() or PyUnicode_AsEncodedString() .

字符映射编解码器 ¶

This codec is special in that it can be used to implement many different codecs (and this is in fact what was done to obtain most of the standard codecs included in the encodings package). The codec uses mapping to encode and decode characters. The mapping objects provided must support the __getitem__() mapping interface; dictionaries and sequences work well.

These are the mapping codec APIs:

PyObject * PyUnicode_DecodeCharmap ( const char  *data , Py_ssize_t  size , PyObject  *mapping , const char  *errors ) ¶

返回值：新引用。

Create a Unicode object by decoding size bytes of the encoded string s using the given 映射 object. Return NULL if an exception was raised by the codec.

若 映射 is NULL , Latin-1 decoding will be applied. Else 映射 must map bytes ordinals (integers in the range from 0 to 255) to Unicode strings, integers (which are then interpreted as Unicode ordinals) or None . Unmapped data bytes – ones which cause a LookupError , as well as ones which get mapped to None , 0xFFFE or '\ufffe' , are treated as undefined mappings and cause an error.

PyObject * PyUnicode_AsCharmapString ( PyObject  *unicode , PyObject  *mapping ) ¶

返回值：新引用。

Encode a Unicode object using the given 映射 object and return the result as a bytes object. Error handling is “strict”. Return NULL if an exception was raised by the codec.

映射 object must map Unicode ordinal integers to bytes objects, integers in the range from 0 to 255 or None . Unmapped character ordinals (ones which cause a LookupError ) as well as mapped to None are treated as “undefined mapping” and cause an error.

PyObject * PyUnicode_EncodeCharmap ( const Py_UNICODE  *s , Py_ssize_t  size , PyObject  *mapping , const char  *errors ) ¶

返回值：新引用。

编码 Py_UNICODE buffer of the given size using the given 映射 object and return the result as a bytes object. Return NULL if an exception was raised by the codec.

Deprecated since version 3.3, will be removed in version 4.0: Part of the old-style Py_UNICODE API；请迁移到使用 PyUnicode_AsCharmapString() or PyUnicode_AsEncodedString() .

The following codec API is special in that maps Unicode to Unicode.

PyObject * PyUnicode_Translate ( PyObject  *unicode , PyObject  *mapping , const char  *errors ) ¶

返回值：新引用。

Translate a Unicode object using the given 映射 object and return the resulting Unicode object. Return NULL if an exception was raised by the codec.

映射 object must map Unicode ordinal integers to Unicode strings, integers (which are then interpreted as Unicode ordinals) or None (causing deletion of the character). Unmapped character ordinals (ones which cause a LookupError ) are left untouched and are copied as-is.

PyObject * PyUnicode_TranslateCharmap ( const Py_UNICODE  *s , Py_ssize_t  size , PyObject  *mapping , const char  *errors ) ¶

返回值：新引用。

Translate a Py_UNICODE buffer of the given size by applying a character 映射 table to it and return the resulting Unicode object. Return NULL when an exception was raised by the codec.

Deprecated since version 3.3, will be removed in version 4.0: Part of the old-style Py_UNICODE API；请迁移到使用 PyUnicode_Translate() . or generic codec based API

用于 Windows 的 MBCS 编解码器 ¶

These are the MBCS codec APIs. They are currently only available on Windows and use the Win32 MBCS converters to implement the conversions. Note that MBCS (or DBCS) is a class of encodings, not just one. The target encoding is defined by the user settings on the machine running the codec.

PyObject * PyUnicode_DecodeMBCS ( const char  *s , Py_ssize_t  size , const char  *errors ) ¶

返回值：新引用。

Create a Unicode object by decoding size bytes of the MBCS encoded string s 。返回 NULL if an exception was raised by the codec.

PyObject * PyUnicode_DecodeMBCSStateful ( const char  *s , Py_ssize_t  size , const char  *errors , Py_ssize_t  *consumed ) ¶

若 consumed is NULL , behave like PyUnicode_DecodeMBCS() 。若 consumed 不是 NULL , PyUnicode_DecodeMBCSStateful() will not decode trailing lead byte and the number of bytes that have been decoded will be stored in consumed .

PyObject * PyUnicode_AsMBCSString ( PyObject  *unicode ) ¶

返回值：新引用。

Encode a Unicode object using MBCS and return the result as Python bytes object. Error handling is “strict”. Return NULL if an exception was raised by the codec.

PyObject * PyUnicode_EncodeCodePage ( int  code_page , PyObject  *unicode , const char  *errors ) ¶

Encode the Unicode object using the specified code page and return a Python bytes object. Return NULL if an exception was raised by the codec. Use CP_ACP code page to get the MBCS encoder.

3.3 版新增。

PyObject * PyUnicode_EncodeMBCS ( const Py_UNICODE  *s , Py_ssize_t  size , const char  *errors ) ¶

返回值：新引用。

编码 Py_UNICODE buffer of the given size using MBCS and return a Python bytes object. Return NULL if an exception was raised by the codec.

Deprecated since version 3.3, will be removed in version 4.0: Part of the old-style Py_UNICODE API；请迁移到使用 PyUnicode_AsMBCSString() , PyUnicode_EncodeCodePage() or PyUnicode_AsEncodedString() .

方法 & 槽 ¶