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  • python-open函数

    open函数,该函数用于文件处理

    操作文件时,一般需要经历如下步骤:

    • 打开文件
    • 操作文件

    一、打开文件

    1

    文件句柄 = open('文件路径', '模式')

    打开文件时,需要指定文件路径和以何等方式打开文件,打开后,即可获取该文件句柄,日后通过此文件句柄对该文件操作。

    打开文件的模式有:

    • r,只读模式(默认)。
    • w,只写模式。【不可读;不存在则创建;存在则删除内容;】
    • a,追加模式。【可读;   不存在则创建;存在则只追加内容;】

    "+" 表示可以同时读写某个文件

    • r+,可读写文件。【可读;可写;可追加】
    • w+,写读
    • a+,同a

    "U"表示在读取时,可以将 自动转换成 (与 r 或 r+ 模式同使用)

    • rU
    • r+U

    "b"表示处理二进制文件(如:FTP发送上传ISO镜像文件,linux可忽略,windows处理二进制文件时需标注)

    • rb
    • wb
    • ab


    • class TextIOWrapper(_TextIOBase):

          """

          Character and line based layer over a BufferedIOBase object, buffer.

         

          encoding gives the name of the encoding that the stream will be

          decoded or encoded with. It defaults to locale.getpreferredencoding(False).

         

          errors determines the strictness of encoding and decoding (see

          help(codecs.Codec) or the documentation for codecs.register) and

          defaults to "strict".

         

          newline controls how line endings are handled. It can be None, '',

          ' ', ' ', and ' '.  It works as follows:

         

          * On input, if newline is None, universal newlines mode is

            enabled. Lines in the input can end in ' ', ' ', or ' ', and

            these are translated into ' ' before being returned to the

            caller. If it is '', universal newline mode is enabled, but line

            endings are returned to the caller untranslated. If it has any of

            the other legal values, input lines are only terminated by the given

            string, and the line ending is returned to the caller untranslated.

         

          * On output, if newline is None, any ' ' characters written are

            translated to the system default line separator, os.linesep. If

            newline is '' or ' ', no translation takes place. If newline is any

            of the other legal values, any ' ' characters written are translated

            to the given string.

         

          If line_buffering is True, a call to flush is implied when a call to

          write contains a newline character.

          """

          def close(self, *args, **kwargs): # real signature unknown

              关闭文件

              pass

          def fileno(self, *args, **kwargs): # real signature unknown

              文件描述符 

              pass

          def flush(self, *args, **kwargs): # real signature unknown

              刷新文件内部缓冲区

              pass

          def isatty(self, *args, **kwargs): # real signature unknown

              判断文件是否是同意tty设备

              pass

          def read(self, *args, **kwargs): # real signature unknown

              读取指定字节数据

              pass

          def readable(self, *args, **kwargs): # real signature unknown

              是否可读

              pass

          def readline(self, *args, **kwargs): # real signature unknown

              仅读取一行数据

              pass

          def seek(self, *args, **kwargs): # real signature unknown

              指定文件中指针位置

              pass

          def seekable(self, *args, **kwargs): # real signature unknown

              指针是否可操作

              pass

          def tell(self, *args, **kwargs): # real signature unknown

              获取指针位置

              pass

          def truncate(self, *args, **kwargs): # real signature unknown

              截断数据,仅保留指定之前数据

              pass

          def writable(self, *args, **kwargs): # real signature unknown

              是否可写

              pass

          def write(self, *args, **kwargs): # real signature unknown

              写内容

              pass

          def __getstate__(self, *args, **kwargs): # real signature unknown

              pass

          def __init__(self, *args, **kwargs): # real signature unknown

              pass

          @staticmethod # known case of __new__

          def __new__(*args, **kwargs): # real signature unknown

              """ Create and return a new object.  See help(type) for accurate signature. """

              pass

          def __next__(self, *args, **kwargs): # real signature unknown

              """ Implement next(self). """

              pass

          def __repr__(self, *args, **kwargs): # real signature unknown

              """ Return repr(self). """

              pass

          buffer = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default

          closed = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default

          encoding = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default

          errors = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default

          line_buffering = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default

          name = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default

          newlines = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default

          _CHUNK_SIZE = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default

          _finalizing = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default

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  • 原文地址:https://www.cnblogs.com/fuyuteng/p/8482477.html
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