// JScript 文件

  
  function return_validator()
  {
        var vNum;
        vNum = Math.random();
        vNum = Math.round(vNum*10000);
        
        document.getElementById("img_valid").src="Validator.aspx?num="+vNum;
  }  
  
  

function isValid()
{ 
    var tbxUserName = document.all.tbx_userName;
    var tbxPassword = document.all.tbx_password;
    var tbxValid = document.all.tbx_valid;

    if (tbxUserName.value.trim().length == 0 || tbxPassword.value.trim().length == 0 || tbxValid.value.trim().length == 0)
    { 
        alert("用户名或密码或验证码不能为空!");
        return false;
    }
    
    return true;
   
}