直接上代码
<textarea id="textarea1" onkeyup="AutoExpand(this)" onfocus="AutoExpand(this)">
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<script type="text/javascript">
var InitHeight = 20;
function AutoExpand(e) {
var HideTextarea = document.getElementById("__hidetextarea");
if (!HideTextarea) {
HideTextarea = document.createElement("textarea");
HideTextarea.id = "__hidetextarea";
HideTextarea.style.borderWidth = 0;
document.body.appendChild(HideTextarea);
}
HideTextarea.value = e.value;
HideTextarea.style.height = "0px";
HideTextarea.style.overflow = "hidden";
var x = HideTextarea.scrollHeight + "必须先计算下scrollHeight的值,否则,scrollHeight 的值将固定?";
delete x;
e.style.height = Math.max(Math.max(InitHeight,20), HideTextarea.scrollHeight) + "px";
}
</script>
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结语
以上是小编分享给大家的全部内容了,希望能给大家一个参考,也希望大家多多支持。