class File

The File object provides a means of reading and writing files from JavaScript.

Index

Constructors

• new File(filename, access, typelist)

Properties

• access
• byteorder
• eof
• filename
• filetype
• foldername
• isopen
• linebreak
• position
• typelist

Methods

• close(text)
• open(filename)
• readbytes(count)
• readchars(count)
• readfloat32(count)
• readfloat64(count)
• readint16(count)
• readint32(count)
• readline(maximumCount)
• readstring(count)
• writebytes(bytes)
• writechars(chars)
• writefloat32(floats)
• writefloat64(floats)
• writeint16(ints)
• writeint32(ints)
• writeline(text)
• writestring(text)

new File(filename, access, typelist)

new File(
  filename?: string,
  access?: FileAccess,
  typelist?: FileFourCharacterCode[],
);

Create a file reference for reading or writing

By default, typelist is empty. If filename includes an extension, then it is not necessary to supply a typelist. If filename does not include an extension, then File will look for a file with one of the extensions specified by typelist. Note that the four-character code may not match the file extension.

Given arguments, the File constructor will open the file automatically if the file can be opened.

Examples

var f = new File("myfile.txt", "write");
post(f.isopen); // true, if myfile.txt is in the Max search path
f.close();

It's also possible to create an empty File object, and to configure it after the fact. In this case, the File object must be opened explicitly.

var f = new File();
f.filename = "myfile.txt";
f.access = "write";
f.open();
post(f.isopen); // true, if myfile.txt is in the Max search path
f.close();

If for some reason the file could not be opened, then File.isopen will return false.

access FileAccess

File access permissions: "read", "write", or "readwrite". By default, this value is "read".

byteorder FileEndianness

The assumed file byteorder (endianness): "big", "little", or "native". By default, this value is "native".

close(text)

Closes the currently open file.

close(text?: string): void;

eof number

The location of the end of file, in bytes. If set past the end of current file, File will append NULL bytes.

filename string

The current filename.

filetype FileFourCharacterCode

The four-character code for the file type.

foldername string read-only

The absolute path to parent folder.

isopen boolean read-only

Return a true/false indicating if the File constructor is successful in finding and opening the file.

linebreak FileLineEndingStyle

The line break convention to use when writing lines. Defaults to "native"

open(filename)

Opens the file specified by the filename argument. If no argument is specified, it will open the last opened file, or the value stored in the filename property. Check File.isopen to see if the file was openend successfully.

open(filename?: string): void;

position number

The current file position, in bytes. Set this to offset the file write position forward or backwards.

readbytes(count)

Read bytes to an array

Reads and returns an array containing up to count numbers, read as bytes from the file, starting at the current file position. The file position is updated accordingly.

readbytes(count: number): number[];

readchars(count)

Read bytes to an array of single character strings

Reads and returns an array containing the single character strings, read as characters from the file, starting at the current file position. The file position is updated accordingly.

readchars(count: number): string[];

readfloat32(count)

Read from a file as 32-bit floating point numbers

Reads and returns an array containing the numbers read as 32-bit floating point numbers from the file, starting at the current file position. The byteorder property is taken into account when reading these values. The file position is updated accordingly.

readfloat32(count: number): number[];

readfloat64(count)

Read from a file as 64-bit floating point numbers

Reads and returns an array containing the numbers read as 64-bit floating point numbers from the file, starting at the current file position. The byteorder property is taken into account when reading these values. The file position is updated accordingly.

readfloat64(count: number): number[];

readint16(count)

Read from a file as 16-bit signed integers

Reads and returns an array containing the numbers read as signed 16-bit integers from the file, starting at the current file position. The byteorder property is taken into account when reading these values. The file position is updated accordingly.

readint16(count: number): number[];

readint32(count)

Read from a file as 32-bit signed integers

Reads and returns an array containing the numbers read as signed 32-bit integers from the file, starting at the current file position. The byteorder property is taken into account when reading these values. The file position is updated accordingly.

readint32(count: number): number[];

readline(maximumCount)

Read a line of text

Reads and returns a string containing up to maximumCount characters or up to the first line break as read from the file, starting at the current file position. The file position is updated accordingly The default maximum count value is 512. This can be increased by specifying a new maximum count as the argument.

readline(maximumCount: number): string;

readstring(count)

Read a string of text

Reads and returns a string containing up to char_count characters as read from the file, starting at the current file position. Unlike File.readline(), line breaks are not considered. The file position is updated accordingly.

readstring(count: number): string;

typelist FileFourCharacterCode[]

An array file type codes to filter by when opening a file. By default, this is the empty array.

writebytes(bytes)

Write an array of bytes

Writes the numbers contained in the bytes argument as bytes to the file, starting at the current file position. The file position is updated accordingly.

writebytes(bytes: number[]): void;

writechars(chars)

Write single character strings

Writes the single character strings contained in the chars argument as characters to the file, starting at the current file position. The file position is updated accordingly.

writechars(chars: string[]): void;

writefloat32(floats)

Write numbers as 32-bit floating point numbers

Writes the numbers contained in the floats argument as 32-bit floating point numbers to the file, starting at the current file position. The byteorder property is taken into account when writing these values. The file position is updated accordingly.

writefloat32(floats: number[]): void;

writefloat64(floats)

Write numbers as 64-bit floating point numbers

Writes the numbers contained in the floats argument as 64-bit floating point numbers to the file, starting at the current file position. The byteorder property is taken into account when writing these values. The file position is updated accordingly.

writefloat64(floats: number[]): void;

writeint16(ints)

Write numbers as 16-bit signed integers

Writes the numbers contained in the ints argument as signed 16-bit integers to the file, starting at the current file position. The byteorder property is taken into account when writing these values. The file position is updated accordingly.

writeint16(ints: number[]): void;

writeint32(ints)

Write numbers as 32-bit signed integers

Writes the numbers contained in the ints argument as signed 32-bit integers to the file, starting at the current file position. The byteorder property is taken into account when writing these values. The file position is updated accordingly.

writeint32(ints: number[]): void;

writeline(text)

Write a line of text

Writes the characters contained in the string argument as characters to the file, starting at the current file position, and inserts a line break appropriate to the linebreak property. The file position is updated accordingly.

writeline(text: string): void;

writestring(text)

Write a string of text

Writes the characters contained in the string argument as characters to the file, starting at the current file position. Unlike File.writeline(), no line break is inserted. The file position is updated accordingly.

writestring(text: string): void;