give some explanation about bind() function in JavaScript

Question

I saw the source code in the MSD

// Define the original function with four parameters.
var displayArgs = function (val1, val2, val3, val4) {
    document.write(val1 + " " + val2 + " " + val3 + " " + val4);
}

var emptyObject = {};

// Create a new function that uses the 12 and "a" parameters
// as the first and second parameters.
var displayArgs2 = displayArgs.bind(emptyObject, 12, "a");

// Call the new function. The "b" and "c" parameters are used
// as the third and fourth parameters.
displayArgs2("b", "c");

// Output: 12 a b c

I can not understand how this source code is working. Bind function can map parameters automatically? Here, it binds two parameters second times.

developer.mozilla.org/en/docs/Web/JavaScript/Reference/… Bind can take multiple arguments. The first argument will be used as the value of this and the rest of the parameters will be passed in as arguments when the function is invoked — blessanm86
– blessanm86, Commented Mar 11, 2016 at 2:15

chmod · Accepted Answer · 2016-03-11 02:23:09Z

1

The first argument is always the this value that you want to pass and the rest of the arguments are arguments to your function. You can pass these arguments partially.

What that means is if you have the partial arguments now and you want to pass the rest of the arguments later when available, you can do that by having this bound function.

HTH.

answered Mar 11, 2016 at 2:23

chmod

646 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

give some explanation about bind() function in JavaScript

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related