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<script type="text/javascript">
//div的滚动条滚动事件
function doScroll(){
//获取协议和按钮的DOM
var d = document.getElementById(‘xieyi‘);
var btn = document.getElementById(‘btn‘);
//判断是否滚动到最底部了
if(d.scrollTop + d.offsetHeight > 200){
btn.disabled = false;//恢复按钮可用
}
}
</script>
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<body style="text-align:center">
<div style="width:200px;height:150px; overflow-y:
scroll;margin:5px auto;border:1px solid black;"
onscroll="doScroll()" id="xieyi">
请认真阅读本协议。。。<br>
...<br>
...<br>
...<br>
...<br>
...<br>
...<br>
...<br>...<br>
协议 end.
</div><br>
<input type="button" value="注册" id="btn" disabled="disabled"/>
</body>
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