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JavaScript JavaScript Foundations Objects Call and Apply

the apply method

what is wrong with this code. the last line in particular <body> <h1>JavaScript Foundations</h1> <h2>Objects: Call and Apply</h2> <script> var genericGreet = function(name, mood) { name = name || "you"; mood = mood || "good"; return "Hello " + name + ", my name is " + this.name + " and I am in a " + mood + " mood!"; }

  var andrew = {
    name: "Andrew"
  }

  var args1 = ["Michael", "awesome", ":)"];

  var greeting = genericGreet;
  greeting.apply(andrew, args1);
</script>

</body>

2 Answers

Andrew Corcoran
Andrew Corcoran
20,552 Points

Hi Alexander,

When the code is run as you have it, the variable greeting is set to the function genericGreet and then you are calling the apply() method on the greeting variable. However this will not actually set the greeting variable to the correct value.

In order to set the greeting variable in the context of 'andrew' with the array of arguments, 'args1' you should call the apply() method directly on genericGreet in the variable declaration. This should look like the code sample below.

var greeting = genericGreet.apply(andrew,args1);
Irfan Ullah
Irfan Ullah
6,869 Points

I was writing like below and was giving me error when I checked it in browser console it was perfectly fine. Thanks Andrew for your help.

var andrew = {
        name: "Andrew",
       greeting:genericGreet
      }

   var args1 = ["Michael", "awesome", ":)"];
      var greeting = genericGreet;
     greeting.apply(andrew,args1);