仿QQ签名
<html>
<script src="http://code.jquery.com/jquery-git.js"></script>
<SCRIPT LANGUAGE="JavaScript">
var maxCharNum = 21
//事件绑定
$(document).ready(function(){
$('#charnum').html(maxCharNum);
changeCharnum('#sign_content',maxCharNum);
//按键改变字数
$("#sign_content").keyup(function(event){//表名在节点sign_content获取焦点之后绑定keyup事件
changeCharnum(this,maxCharNum);
if(event.ctrlKey&&event.keyCode==13)addSign();//绑定ctrl+回车键发布签名
}).blur(function(){
changeCharnum(this,maxCharNum);
}).focus(function(){
changeCharnum(this,maxCharNum);
});
});
//改变字数
function changeCharnum (obj,num){
if( $(obj).length >0 ){
var len = $(obj).val().length;
var charNumObj = $('#charnum');
if(len==0){
charNumObj.html( (num-len) );
}else if( len > num ){
charNumObj.css('color','red').html( (num-len) );
}else if( len <= num ){
charNumObj.css('color','').html( (num-len) );
}
}
}
//发布前内容检测
function checkTextArea (num){
//内容不能为空
if($('#sign_content').val() == '' ){
alert('内容不能为空');
return false;
}
//内容字数不能超过maxCharNum个字
if( $('#sign_content').val().length > num ){
alert('内容不能超过'+maxCharNum+'个字符');
return false;
}
return true;
}
//发表
function addSign(){
if( checkTextArea(maxCharNum) ){
//设置发布按钮不可点击，取消ctrl+enter的绑定操作
$('#button_addSign').attr('disabled','disabled');
var content = $("#sign_content").val();
var len = $('#sign_content').val().length;
$.post(addSign.action,{content:content,len:len},function(txt){
if( txt == '1' ){
alert('超过'+maxCharNum+'个字符');
return ;
}
if( txt ){
$('#sign_content').val('');
$('#button_addSign').attr('disabled','');
location.reload();
}else{
alert('发布失败');
}
});
}
}
</SCRIPT>
<body >
<textarea id='sign_content' keydown="changeCharnum()">
</textarea>
还剩余<span id='charnum'></span>个字<br />
<button id="button_addSign" onclick="addSign()">发表</button>
</body>
</html>
