JavaScript with function ()

Question

Is with()part of the built-in JavaScript library? What browsers support it?

Answer 1

This is part of the JavaScript 1.5 specification . Therefore, it must be supported by the main browser.

Answer 2

Yes, that is part of it. Each browser that supports JavaScript 1.5 supports it (these are all major browsers or class A).

However, using the with statement is not recommended .

Answer 3

, , , (.)

// BAD use of with is to replace this:
// some.expression.with.lots.of.dots.x = 10;
// some.expression.with.lots.of.dots.y = 20;
// with this:
with (some.expression.with.lots.of.dots) {
    x = 10;
    y = 20;
}

, :

// Acceptable use of with is to close over a variable by value.
var functions = [];
for (var i = 0; i < 5; i++) {
    with ({ j: i }) {
        functions[i] = function() { return j; };
    }
}

, , , , .

Answer 4

- JS, - , Google-fu . , - , , , .

: , , , . .;)

Answer 5

, JavaScript with.

: ,