function login(returnHander)
{	       
         var UserNameObj   = document.getElementById("txtUserName");
         var PasswordObj   = document.getElementById("txtPassword");
         var VerifyCodeObj = document.getElementById("txtVerifyCode");
    
         if (UserNameObj.value == "")
         {
             alert("请输入用户名！");
             UserNameObj.focus();
             return false
         }  
         
         if (VerifyCodeObj != null)
         {
             if (VerifyCodeObj.value == "")
             {
                 alert("请输入验证码！");
                 VerifyCodeObj.focus();
                 return false;
             }  
         }        
          
         if ((typeof(returnHander)) == 'undefined' || (returnHander == null))
         {
              returnHander = loginToPage; 
         }	     
         callActionService("MemberLogin",returnHander);
	    
}
 
function loginToPage(result)
{
         if (startsWith(result,"error:"))         
             alert(result);
         else                  
             eval(result);             
         
}