How can I check if two arrays in Javascript are equal?

Question

Is there a way to check if two JavaScript ArrayBuffers are equal? I would like to write a test for the message composition method. The only way I found is to convert the ArrayBuffer to a string and then compare. Did I miss something?

The following code gives false, even if I think this should be true:

(function() {
    'use strict';

    /* Fill buffer with data of Verse header and user_auth
     * command */
    var buf_pos = 0;
    var name_len = 6
    var message_len = 4 + 1 + 1 + 1 + name_len + 1;

    var buf = new ArrayBuffer(message_len);
    var view = new DataView(buf);
    /* Verse header starts with version */
    view.setUint8(buf_pos, 1 << 4); /* First 4 bits are reserved for version of protocol */
    buf_pos += 2;
    /* The lenght of the message */
    view.setUint16(buf_pos, message_len);
    buf_pos += 2;

    buf_pos = 0;
    var buf2 = new ArrayBuffer(message_len);
    var view2 = new DataView(buf);
    /* Verse header starts with version */
    view2.setUint8(buf_pos, 1 << 4); /* First 4 bits are reserved for version of protocol */
    buf_pos += 2;
    /* The lenght of the message */
    view2.setUint16(buf_pos, message_len);
    buf_pos += 2;


    if(buf == buf2){
        console.log('true');
    }
    else{
        console.log('false');
    }


}());

If I try to compare view and view2, it will again be false.

Answer 1

JavaScript == ===.
(.. ).

DataView ArrayView ArrayBuffer .

:

if (  view1.getUint8 (0) == view2.getUint8 (0)
   && view1.getUint16(2) == view2.getUint16(2)) ...

, :

function equal (buf1, buf2)
{
    if (buf1.byteLength != buf2.byteLength) return false;
    var dv1 = new Int8Array(buf1);
    var dv2 = new Int8Array(buf2);
    for (var i = 0 ; i != buf1.byteLength ; i++)
    {
        if (dv1[i] != dv2[i]) return false;
    }
    return true;
}

ArrayBuffer, , DataView/ArrayView , .

Answer 2

. .

let a = new Uint8Array([1, 2, 3, 4]);
let b = new Uint8Array([1, 2, 3, 4]);
if (a.toString() == b.toString()) {
    console.log("Yes");
} else {
    console.log("No");
}