nodejs 里字符串同Buffer之間的互轉

1.string轉buffer

var str = 'hello,world';
var buffer = Buffer.from(str)

buffer的值為

<Buffer 68 65 6c 6c 6f 2c 77 6f 72 6c 64>

轉回字符串

buffer.toString()

hello,world

2.使用 Uint8Array

var array = new Uint8Array(new ArrayBuffer(str.length));
for (var i = 0, il = str.length; i < il; i++) {
    var value = str.charCodeAt(i);
    array[i] = value > 0xFF ? 0x20 : value;
}
var arrBuffer=array.buffer

arrBuffer的值為

ArrayBuffer {
[Uint8Contents]: <68 65 6c 6c 6f 2c 77 6f 72 6c 64>,
byteLength: 11
}

轉成buffer

Buffer.from(array.buffer)

轉成字符串

(Buffer.from(array.buffer)).toString()

<Buffer 68 65 6c 6c 6f 2c 77 6f 72 6c 64>

(Buffer.from(array.buffer)).toString()

hello,world