call、bind、apply Difference and use

1. bind Will change this Point to And the function will not execute immediately The method of passing parameters is separated by commas
2. call Will change this Point to The function will execute immediately The method of passing parameters is separated by commas
3. apply Will change this Point to The function immediately points to The parameter transfer method is passed in the form of an array

	     let fn1 = function (a, b) {
            this.name1 = ' The doll '
            this.age = '40'
            console.log(this, a, b)
        }
        let obj2 = { names: ' anaesthesia ' };
        //  hold obj2 Of this Point to become  fn1 
        fn1.bind(obj2, 2, 3)(); // change this Point to   Not execute 
        fn1.call(obj2, 2, 3); // change this Point to   Automatically 
        fn1.apply(obj2, [2, 3]) // change this Point to   Automatically   The parameter transfer method is array 

The results returned are the same Just pass on and Whether to execute immediately is the same