Buffer
¶
Buffer
objects are used for working with binary data. They can be used much like arrays, but are much more efficient since they only store bytes.
- new Buffer()¶
Constructor method.
Create a new empty buffer.
- Returns:
Buffer
.
EXAMPLE
var buffer = new mupdf.Buffer();
- new Buffer(original)¶
Constructor method.
Create a new buffer with a copy of the data from the original buffer.
- Arguments:
original –
Buffer
.
- Returns:
Buffer
.
EXAMPLE
var buffer = new mupdf.Buffer(buffer);
- readFile(fileName)¶
mutool only
Constructor method.
Create a new buffer with the contents of a file.
- Arguments:
fileName – The path to the file to read.
- Returns:
Buffer
.
EXAMPLE
var buffer = mupdf.readFile("my_file.pdf");
Instance properties
length
mutool only
The number of bytes in the buffer.
Read-only
.
[n]
mutool only
Read/write the byte at index ‘n’. Will throw exceptions on out of bounds accesses.
EXAMPLE
var byte = buffer[0];
Instance methods
- getLength()¶
wasm only
Returns the number of bytes in the buffer.
Read-only
.- Returns:
Integer
.
EXAMPLE
var length = buffer.getLength();
- writeByte(b)¶
Append a single byte to the end of the buffer.
- Arguments:
b – The byte value. Only the least significant 8 bits of the value are appended to the buffer.
EXAMPLE
buffer.writeByte(0x2a);
- readByte(at)¶
wasm only
Read the byte at the supplied index.
- Arguments:
at –
Integer
.
EXAMPLE
buffer.readByte(0);
- writeRune(c)¶
mutool only
Encode a unicode character as UTF-8 and append to the end of the buffer.
- Arguments:
c – The character unicode codepoint.
EXAMPLE
buffer.writeRune(0x4f60); // To append U+4f60 buffer.writeRune(0x597d); // To append U+597d buffer.writeRune(0xff01); // To append U+ff01
- writeLine(...)¶
Append arguments to the end of the buffer, separated by spaces, ending with a newline.
- Arguments:
... – List of arguments.
EXAMPLE
buffer.writeLine("a line");
- write(...)¶
Append arguments to the end of the buffer, separated by spaces.
- Arguments:
... – List of arguments.
EXAMPLE
buffer.write("hello", "world");
- writeBuffer(data)¶
Append the contents of the
data
buffer to the end of the buffer.- Arguments:
data – Data buffer.
EXAMPLE
buffer.writeBuffer(anotherBuffer);
- slice(start end)¶
Create a new buffer containing a (subset of) the data in this buffer. Start and end are offsets from the beginning of this buffer, and if negative from the end of this buffer.
- Arguments:
start – Start index.
end – End index.
- Returns:
Buffer
.
EXAMPLE
var buffer = new Buffer(); buffer.write("hello", "world"); // buffer contains "hello world" var newBuffer = buffer.slice(1, -1); // newBuffer contains "ello worl"
- save(fileName)¶
mutool only
Write the contents of the buffer to a file.
- Arguments:
fileName – Filename to save to.
EXAMPLE
buffer.save("my_buffer_filename");
- asUint8Array()¶
wasm only
Returns the buffer as a
Uint8Array
.- Returns:
Uint8Array
.
EXAMPLE
var arr = buffer.asUint8Array();
- asString()¶
wasm only
Returns the buffer as a
String
.- Returns:
String
.
EXAMPLE
var str = buffer.asString();