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<input type="text" name="mytxt" value=" 12345678 " /><br>
<input type="button" name="cmd1" onclick="mytxt2.value=mytxt.value.trim()" value="È¥Á½±ßµÄ¿Õ¸ñ"/>
<input type="text" name="mytxt2"/><br>
<input type="button" name="cmd1" onclick="mytxt3.value=mytxt.value.ltrim()" value="È¥×ó±ßµÄ¿Õ¸ñ"/>
<input type="text" name="mytxt3"/><br>
<input type="button" name="cmd1" onclick="mytxt4.value=mytxt.value.rtrim()" value="È¥ÓұߵĿոñ"/>
<input type="text" name="mytxt4"/><br>
<script language="javascript">
String.prototype.trim=function(){
return this.replace(/(^s*)|(s*$)/g, "");
}
String.prototype.ltrim=function(){
return this.replace(/(^s*)/g,"");
}
String.prototype.rtrim=function(){
return this.replace(/(s*$)/g,"");
}
</script>
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<script type="text/javascript">
function trim(str){ //ɾ³ý×óÓÒÁ½¶ËµÄ¿Õ¸ñ
return str.replace(/(^s*)|(s*$)/g, "");
}
function ltrim(str){ //ɾ³ý×ó±ßµÄ¿Õ¸ñ
return str.replace(/(^s*)/g,"");
}
function rtrim(str){ //ɾ³ýÓұߵĿոñ
return str.replace(/(s*$)/g,"");
}
</script>
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Since each <script> tag blocks the page from rendering during initial download, it's helpful to limit the total number of <script> tags contained in the page. This applies to both inline scripts as well as those in external files. Every time ......
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<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
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if(true)
{
a = 1;
}
alert(a); //Êä³öɶ£¿
if(true)
{
var a = 1;
}
alert(a); //ÕâÓÖÊä³öʲô£¿
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