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<title>菜鸟教程(runoob.com)</title>
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<h2>JavaScript this 关键字</h2>
<p>实例中 <strong>this</strong> 指向了 person2，即便它是 person1 的方法:</p>

<p id="demo"></p>

<script>
var person1 = {
  fullName: function() {
    return this.firstName + " " + this.lastName;
  }
}
var person2 = {
  firstName:"John",
  lastName: "Doe",
}
var x = person1.fullName.call(person2); 
document.getElementById("demo").innerHTML = x; 
</script>

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