<textarea id="textarea1" onkeyup="AutoExpand(this)" onfocus="AutoExpand(this)">
複製代碼
<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 + "必須先計算下scrollHeight的值,不然,scrollHeight 的值將固定?";
delete x;
e.style.height = Math.max(Math.max(InitHeight,20), HideTextarea.scrollHeight) + "px";
}
</script>
複製代碼
以上是小編分享給你們的所有內容了,但願能給你們一個參考,也但願你們多多支持。javascript