<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">  
<html>  
  <head>  
    <title>js trim函数的例子--www.jb200.com</title>  
    <script type="text/
javascript">  
        String.prototype.trim = function()  
        {  
            return this.replace(/(^s*)|(s*$)/g, "");  
        }  
          
        function check(){  
            var str = document.getElementById("test").value;  
              
            alert(str.trim());  
        }  
    </script>  
  </head>  
    
  <body>  
    <center>  
        <input id="test" type="text" />  
        <input id="but" type="button" value="检验" onclick="check();"/>  
    </center>  
  </body>  
</html>