var code ; //在全局 定义验证码   
     function createCode()   
     {    
       code = "";   
       var codeLength = 4;//验证码的长度   
       var checkCode = document.getElementById("checkCode");   
       var selectChar = new Array(0,1,2,3,4,5,6,7,8,9);//所有候选组成验证码的字符，当然也可以用中文的   
           
       for(var i=0;i<codeLength;i++)   
       {   
         
           
       var charIndex = Math.floor(Math.random()*10);   
       code +=selectChar[charIndex];   
          
          
       }   
//       alert(code);   
       if(checkCode)   
       {   
         checkCode.className="code";   
         checkCode.value = code;   
       }   
          
     }   
        
      function validate ()   
     {   
       var inputCode = document.getElementById("_vcode").value;   
       if(inputCode.length <=0)   
       {   
           alert("请输入验证码！");   
       }   
       else if(inputCode != code )   
       {   
          alert("验证码输入错误！");   
          createCode();//刷新验证码   
       }   
       else   
       {   
         login(); 
       }   
          
       }   
       
       reset = function(){
          $("#txt_name").val("");
          $("#txt_pwd").val("");
          $("#_vcode").val("");
       }
       
       //用户登陆
       login = function(){
          //var username =$("#txt_name").val();encodeURI(encodeURI($("#pro"+id+"").html()))
           var username =encodeURI(encodeURI($("#txt_name").val()));
          var pwd = $("#txt_pwd").val();
          $.ajax({
             type:"get",
             cache:false,
             url:"ajaxpage.aspx?t=login&name="+username+"&pwd="+escape(pwd)+"",
             dataType:"json",
             success:function(data){
               if(data.sta == 0)
               {
                 createCode();
                 alert(data.info);
               }
               if(data.sta == 1)
               {
                  //$.cookie("st_username", "$("#txt_name").val()", { path: '/admin', expires: 7 }); 
                  window.location.href="shop/index.html";
               }
               
             }
          
          })
       }