<body>
<input type="submit" name="button" id="button" value="点击" />
<script type="text/javascript">
document.getElementById("button").onclick=function(){
alert(this.id);
}
document.getElementById("button").click();
function clickFun(){
alert(this.id);
}
var aButton=document.getElementById("button");
clickFun.call(aButton);
//clickFun.call(aButton);
</script>
</body>
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