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The different ways "this" is used in JavaScript
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| // 1 | |
| console.log(this); // refers to the Global Object aka window | |
| // its methods include prompt alert confirm etc... | |
| // 2 | |
| function test() { | |
| console.log(this); | |
| this.method = function inner() {console.log(this)}; | |
| }; // Here again "this" will refer to the global object | |
| test(); | |
| //3 | |
| var obj = new test(); // Since we are using the constructor, this now refers to the new object "test"! | |
| //4 | |
| obj.method(); //infereing methods forced this to be set to its object | |
| // 5: You can also force this to be a certain value using call or apply | |
| function foo(a, b, c) { | |
| this.a = a; | |
| this.b = b; | |
| this.c = c; | |
| } | |
| var bar = {}; | |
| foo.apply(bar, [1, 2, 3]); //this first parameter will be what "this" is | |
| console.log(bar) // bar will be an arry like a: 1, b: 2, c: 3 | |
| foo.call(bar, 4, 5, 6); // same here | |
| console.log(bar) // bar will be an arry like a: 4, b: 5, c: 6 | |
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