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C# ValidationAttribute+Ajax问题_C#_Asp.net Mvc_Ajax.net - Fatal编程技术网

C# ValidationAttribute+Ajax问题

C# ValidationAttribute+Ajax问题,c#,asp.net-mvc,ajax.net,C#,Asp.net Mvc,Ajax.net,我尝试创建ValidationAttribute,它将检查数据库是否存在这样的对象。 它甚至只在不包括 有人能告诉我们如何通过Ajax开始工作吗 public class UsernameBaseCheckAttribute : ValidationAttribute { SimplebdLinqDataContext db = new SimplebdLinqDataContext(); //DataContext(Linq) public override bool Is

我尝试创建ValidationAttribute,它将检查数据库是否存在这样的对象。 它甚至只在不包括

有人能告诉我们如何通过Ajax开始工作吗

public class UsernameBaseCheckAttribute : ValidationAttribute 
{
    SimplebdLinqDataContext db = new SimplebdLinqDataContext(); //DataContext(Linq)

    public override bool IsValid(object value)
    {


        if (!db.Users.Any(u => u.UserName == (string)value))
        {
            return true;

        }
        else
        {
            return false;
        }
    }
}

看看这个。我认为您需要按照他创建javascript函数的结尾处的说明进行操作,该函数将处理客户端验证。在您的情况下,需要进行ajax调用以确定输入是否有效,因为需要对照数据库进行检查