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<body>
<h1>JavaScript <b>this</b> 关键词</h1>
<p>在函数中,默认地,<b>this</b> 引用全局对象。</p>
<p>在严格模式中,<b>this</b><b>undefined</b>,因为严格模式不允许默认绑定:</p>
<p id="demo"></p>
<script>
"use strict";
document.getElementById("demo").innerHTML = myFunction();
function myFunction() {
  return this;
}
</script>
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