Page 175 - JavaScript
P. 175

SomeClass.prototype.handleEvent = function(event) {
                   var fn = this[event.type];
                   if (fn) {
                      fn.apply(this, arguments);
                   }
                 };

                 SomeClass.prototype.click = function(event) {
                   console.log(this.msg);
                 };


        Callback using Arrow function


        Using arrow function as callback function can reduce lines of code.


        The default syntax for arrow function is


         () => {}


        This can be used as callbacks

        For example if we want to print all elements in an array [1,2,3,4,5]


        without arrow function, the code will look like this


         [1,2,3,4,5].forEach(function(x){
                          console.log(x);
                     }


        With arrow function, it can be reduced to


         [1,2,3,4,5].forEach(x => console.log(x));


        Here the callback function function(x){console.log(x)} is reduced to x=>console.log(x)

        Read Callbacks online: https://riptutorial.com/javascript/topic/2842/callbacks





























        https://riptutorial.com/                                                                             132
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