<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html>
<head>
</head>
<body>
<textarea style=" height:16px; line-height:16px; 800px;" id="textarea3"></textarea>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.5.2/jquery.min.js"></script>
<script type="text/javascript" src="textareaAutoHeight.js"></script>
<script type="text/javascript">
$("#textarea3").textareaAutoHeight({ minHeight: 50, maxHeight: 200}); //最小高度为50px，最大高度为200px
</script>
</body>
</html>
textareaAutoHeight.js代码如下：
/// <reference path="jquery-1.5.1.min.js" />
$.fn.extend({
textareaAutoHeight: function(options) {
this._options = {
minHeight: 0,
maxHeight: 1000
}
this.init = function() {
for (var p in options) {
this._options[p] = options[p];
}
if (this._options.minHeight == 0) {
this._options.minHeight = parseFloat($(this).height());
}
for (var p in this._options) {
if ($(this).attr(p) == null) {
$(this).attr(p, this._options[p]);
}
}
$(this).keyup(this.resetHeight).keydown(this.resetHeight).change(this.resetHeight)
.focus(this.resetHeight);
}
this.resetHeight = function() {
var _minHeight = parseFloat($(this).attr("minHeight"));
var _maxHeight = parseFloat($(this).attr("maxHeight"));
if (!$.browser.msie) {
$(this).height(0);
}
var h = parseFloat(this.scrollHeight);
h = h < _minHeight ? _minHeight :
h > _maxHeight ? _maxHeight : h;
$(this).height(h);//scrollTop(h);
if (h >= _maxHeight) {
$(this).css("overflow-y", "scroll");
}
else {
$(this).css("overflow-y", "hidden");
}
}
this.init();
}
});