# File Object [AHK_L 42+]

Provides an interface for file input/output. FileOpen returns an object of this type.

## Read

Reads a string of characters from the file and advances the file pointer.

    String := File.Read([Characters])

Characters | The maximum number of characters to read. If omitted, the rest of the file is read and returned as one string. If the File object was created from a handle to a non-seeking device such as a console buffer or pipe, omitting this parameter may cause the method to fail or return only what data is currently available.
Returns | A string.

## Write

Writes a string of characters to the file and advances the file pointer.

    File.Write(String)

String | A string.
Returns | The number of bytes (not characters) that were written.

## ReadLine

Reads a line of text from the file and advances the file pointer.

    Line := File.ReadLine()

Returns | A line of text. This may include ``n`, ``r`n` or ``r` depending on the file and EOL flags used to open the file.

## WriteLine

Writes a string of characters followed by ``n` or ``r`n` depending on the flags used to open the file. Advances the file pointer.

    File.WriteLine([String])

String | An optional string.
Returns | The number of bytes (not characters) that were written.

## ReadNum

Reads a number from the file and advances the file pointer.

    Num := File.ReadNumType()

NumType | One of the following specified directly as part of the function name: UInt, Int, Int64, Short, UShort, Char, UChar, Double, or Float.
Returns | A number if successful, otherwise an empty string.

## WriteNum

Writes a number to the file and advances the file pointer.

    File.WriteNumType(Num)

NumType | One of the following specified directly as part of the function name: UInt, Int, Int64, Short, UShort, Char, UChar, Double, or Float.
Num | A number.
Returns | The number of bytes that were written. For instance, WriteUInt returns 4 if successful.

## RawRead

Read raw binary data from the file into memory. If a var is specified, it is expanded automatically when necessary.

    File.RawRead(VarOrAddress, Bytes)

VarOrAddress | A variable or memory address to which the data will be copied. Usage is similar to NumGet.
Bytes | The maximum number of bytes to read.
Returns | The number of bytes that were read.

## RawWrite

Write raw binary data to the file.

    File.RawWrite(VarOrAddress, Bytes)

VarOrAddress | A variable containing the data or the address of the data in memory. Usage is similar to NumPut.
Bytes | The number of bytes to write.
Returns | The number of bytes that were written.

## Seek

Moves the file pointer.

    File.Seek(Distance [, Origin = 0])
    File.Position := Distance
    File.Pos := Distance

Distance | Distance to move, in bytes. Lower values are closer to the beginning of the file.
Origin | Starting point for the file pointer move. Must be one of the following: 0 (SEEK_SET): Beginning of the file. Distance must be zero or greater. 1 (SEEK_CUR): Current position of the file pointer. 2 (SEEK_END): End of the file. Distance should usually be negative. If omitted, Origin defaults to SEEK_END when Distance is negative and SEEK_SET otherwise.
Returns | A non-zero value if successful, otherwise zero.

## Tell

    Pos := File.Tell()
    Pos := File.Position
    Pos := File.Pos

Returns | The current position of the file pointer, where 0 is the beginning of the file.

## Length

Retrieves or sets the size of the file.

    FileSize := File.Length
    File.Length := NewSize

NewSize | The new size of the file, in bytes.
Returns | The size of the file, in bytes.

This property should be used only with an actual file. If the File object was created from a handle to a pipe, it may return the amount of data currently available in the pipe's internal buffer, but this behaviour is not guaranteed.

## AtEOF

    IsAtEOF := File.AtEOF

Returns | A non-zero value if the file pointer has reached the end of the file, otherwise zero.

This property should be used only with an actual file. If the File object was created from a handle to a non-seeking device such as a console buffer or pipe, the returned value may not be meaningful, as such devices do not logically have an "end of file".

## Close

Closes the file, flushes any data in the cache to disk and releases the share locks. Although the file is closed automatically when the object is freed, it is recommended to close the file as soon as possible.

    File.Close()

No parameters or return value.

## Encoding

Retrieves or sets the text encoding used by this file object.

    Encoding := File.Encoding
    File.Encoding := Encoding

Encoding | A string in the format accepted by FileEncoding.

## __Handle

    File.__Handle

Returns | A system file handle, intended for use with DllCall. See CreateFile.

File objects internally buffer reads or writes. If data has been written into the object's internal buffer, it is committed to disk before the handle is returned. If the buffer contains data read from file, it is discarded and the actual file pointer is reset to the logical position indicated by `File.Pos`.