var code ; 
     function createCode()   
     {    
      code = "";   
       var codeLength = 4;   
       var checkCode = document.getElementById("checkCode");   
      var selectChar = new Array(0,1,2,3,4,5,6,7,8,9,'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z');
          
      for(var i=0;i<codeLength;i++)   
       {   
         
          
      var charIndex = Math.floor(Math.random()*36);   
      code +=selectChar[charIndex];   
          
          
       }   
//       alert(code);   
       if(checkCode)   
      {   
        checkCode.className="code";   
         checkCode.value = code;   
      }   
          
     }   
        
      function validate (msg1,msg2)   
    {   
       var inputCode = document.getElementById("input1").value;   
      if(inputCode.length <=0)   
       {   
           alert(msg1);   
return false; 
       }   
      else if(inputCode.toUpperCase() != code )   
       {   
         alert(msg2);   
          createCode();//  
	return false; 
      }   
      else   
      {   

return true; 
       }   
         
       }