javascript - this keyword in a class method -

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var mc = function(map){     var init = function(imap){         alert("init " + + " with");     }     init(map); }; var m = new mc({});

why getting value of [object window]? window object??

yes! because init variable of mc, share scope (which global scope, window object).

however. if changed following:

var mc = function(map){     this.init = function(imap){         alert("init " + + " with");     }     this.init(map); }; var m = new mc({});

then this inside init reference instance.


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