Convert a 32bit integer into 4 bytes of data in javascript

Question

I was asked to convert the integers to 32-bit binary numbers. So is used integer.toString(2) and got the required value in 32-bit binary format of 0\'sand 1\'s. But

Answer 1

Now you can use ArrayBuffer and DataView. They are native so the performance will be much better if you need to use it very often.

function toBytesInt32 (num) {
    arr = new ArrayBuffer(4); // an Int32 takes 4 bytes
    view = new DataView(arr);
    view.setUint32(0, num, false); // byteOffset = 0; litteEndian = false
    return arr;
}

equals to

function toBytesInt32 (num) {
    arr = new Uint8Array([
         (num & 0xff000000) >> 24,
         (num & 0x00ff0000) >> 16,
         (num & 0x0000ff00) >> 8,
         (num & 0x000000ff)
    ]);
    return arr.buffer;
}

which use javascript bitwise operators to achieve that.