可以通过按钮来控制调节文本框高度，根据自己的需求来设定默认高度，也可以自定义最大值。
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<meta http-equiv="content-Type" content="text/html;charset=gb2312">
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<title>按钮控制调节文本框高度特效_武鸣人</title>
<style type="text/css">
/* Reset style */
* {margin:0; padding:0; word-break:break-all;}
body {background:#FFF; color:#333; font:12px/1.4em Helvetica, Arial, sans-serif;}
h1, h2, h3, h4, h5, h6 {font-size:1em;}
a {color:#333; text-decoration:none;}
a:hover {text-decoration:underline;}
ul, li {list-style:none;}
fieldset, img {border:none;}
input, textarea, select, button {font:12px Helvetica, Arial, sans-serif;}
.button {padding:0 10px; height: 22px; border: 1px solid; border-color: #EEE #999 #999 #EEE; background: #DDD; color: #333; line-height: 20px; cursor: pointer; margin-left:2px;}
.submit {padding:0 10px; height: 22px; border: 1px solid; border-color: #DDD #CC8305 #CC8305 #DDD; background: #FFA200; color: #FFF; line-height: 20px; letter-spacing: 1px; cursor: pointer;}
/* edit_wuming style */
#edit_wuming {width:300px; margin:50px;}
.edit_wuming_caption {width:100%; overflow:hidden; margin-bottom:1px; overflow:hidden;}
.edit_wuming_caption span {display:block; float:left; margin:0 5px 0 0px; padding:2px 10px; background:#DDD; cursor:pointer;}
.edit_wuming_caption span:hover {background:#EEE;}
#edit_wuming textarea {width:300px; height:80px; margin:0; padding:0;}
</style>
<script type="text/javascript">
var addH=1;
function addHeight_wuming_ren() {
if (!document.getElementById('www_wuming_ren')) return flase;
var comment = document.getElementById('www_wuming_ren');
var nowH = parseInt(comment.style.height);
if (nowH < 250) {
nowH+=2;
comment.style.height=nowH+"px";
addH++;
if (addH > 25){
addH=1;
} else {
window.setTimeout("addHeight_wuming_ren()","10");
}
}
}//武鸣人网站https://www.wuming.ren 网站很好记住，wuming.ren(武鸣拼音.ren域名后缀)
function minHeight_wuming_ren() {
if (!document.getElementById('www_wuming_ren')) return flase;
var comment = document.getElementById('www_wuming_ren');
var nowH = parseInt(comment.style.height);
if (nowH > 50) {
nowH-=2;
comment.style.height=nowH+"px";
addH++;
if (addH > 25){
addH=1;
} else {
window.setTimeout("minHeight_wuming_ren()","10");
}
}
}//武鸣人网站https://www.wuming.ren 网站很好记住，wuming.ren(武鸣拼音.ren域名后缀)
</script>
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<body>
<a href="https://www.wuming.ren">武鸣人</a>，各种信息资源免费发布，分享励志语录经典短句，减肥健身常识，各种js特效代码。网站很好记住，wuming.ren(武鸣拼音.ren域名后缀)<hr>
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<script type="text/javascript" src="https://www.wuming.ren/ad/tc.js"></script>
<script type="text/javascript" src="https://www.wuming.ren/ad/a.js"></script>
<div id="edit_wuming">
<div class="edit_wuming_caption">
<span onclick="addHeight_wuming_ren()">放大</span>
<span onclick="minHeight_wuming_ren()">缩小</span>
</div>
<div><textarea id="www_wuming_ren" name="www_wuming_ren" tabindex="1" rows="8" style="height:100px">武鸣人，各种信息资源免费发布，分享励志语录经典短句，减肥健身常识，各种js特效代码！
</textarea>
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</body>
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