回顾：内置验证属性。

示例：注册时邮箱后缀必须是 52abp.com。

具体步骤

编写验证用的特性：

public class ValidEmailDomainAttribute : ValidationAttribute
{
    private readonly string _allowedDomain;
    public ValidEmailDomainAttribute(string allowedDomain)
    {
        _allowedDomain = allowedDomain;
    }
    public override bool IsValid(object value)
    {
        var strings = value.ToString().Split('@');
        return strings[1].ToUpper() == _allowedDomain.ToUpper();
    }
}

在 ViewModel 中使用验证特性：

public class RegisterViewModel
{
    [Required(ErrorMessage = "邮箱地址不能为空")]
    [EmailAddress]
    [Display(Name = "邮箱地址")]
    [Remote(action: "IsEmailInUse", controller: "Account")]
    [ValidEmailDomain(allowedDomain: "52abp.com",ErrorMessage = "邮箱后缀必须是 52abp.com")]
    public string Email { get; set; }
    ...
}

效果：