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<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<TITLE>枫芸志 » 文本框textarea高度自适应增长/伸缩</TITLE>
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<textarea id="txtContent" rows="5" cols="50" onkeyup="ResizeTextarea()" style="overflow-y:hidden;">Textarea高度随内容自适应地增长，无滚动条
晴枫制作
http://www.111cn.net</textarea>
<script type="text/javascript">
// 最小高度
var minRows = 5;
// 最大高度，超过则出现滚动条
var maxRows = 12;
function ResizeTextarea(){
var t = document.getElementById('txtContent');
if (t.scrollTop == 0) t.scrollTop=1;
while (t.scrollTop == 0){
if (t.rows > minRows)
t.rows--;
else
break;
t.scrollTop = 1;
if (t.rows < maxRows)
t.style.overflowY = "hidden";
if (t.scrollTop > 0){
t.rows++;
break;
}
}
while(t.scrollTop > 0){
if (t.rows < maxRows){
t.rows++;
if (t.scrollTop == 0) t.scrollTop=1;
}
else{
t.style.overflowY = "auto";
break;
}
}
}
</script>
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