EN
JavaScript - how to use '.call(...)' method with (or instead) 'new' operator
5 points
In this article we would like to show how to create object with MyClass.call(...) method instead of new operator in JavaScript.
Simple solution:
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function MyClass(a, b) {2
console.log(a + ' ' + b);3
this.print = function(c, d) {4
console.log(a + ' ' + b + ' -> ' + c + ' ' + d);5
};6
}7
8
var object = { };9
MyClass.call(object, 'a', 'b');10
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object.print('c', 'd');Note: read this article to see
MyClass.apply(...)method examples.
Check below alternative solutions:
There are few different ways how to achieve same effect, what was presenbted in this section.
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function MyClass(a, b) {2
console.log(a + ' ' + b);3
this.print = function(c, d) {4
console.log(a + ' ' + b + ' -> ' + c + ' ' + d);5
};6
}7
8
var object = new (MyClass.bind.call(MyClass, null, 'a', 'b'));9
object.print('c', 'd');xxxxxxxxxx1
function MyClass(a, b) {2
console.log(a + ' ' + b);3
this.print = function(c, d) {4
console.log(a + ' ' + b + ' -> ' + c + ' ' + d);5
};6
}7
8
var object = new (Function.prototype.bind.call(MyClass, null, 'a', 'b'));9
object.print('c', 'd');