获取属性的参数和值

本文关键字:参数 属性 获取 | 更新日期: 2023-09-27 18:18:49

嗨,我正在使用反射来迭代此模型的属性的属性:

[Required(ErrorMessage = "Username is required")]
[MaxLength(50, ErrorMessage = "Username should not have more then 50 chars")]
[MinLength(25 , ErrorMessage = "Username should have at least 25 chars")]
 public string UserName { get; set; }
 [Required(ErrorMessage = "Password is required")]
 [StringLength(25)]
 public string Password { get; set; }
 public bool RememberMe { get; set; }
foreach (var propertyInfo in type)
       var attr = propertyInfo.CustomAttributes;
       foreach (var customAttributeData in attr)
       {
             var name = customAttributeData.AttributeType.Name;
       }
}

我设法获得属性名称,但我在获取属性构造函数参数的键/值对时遇到麻烦。

我如何能够访问例如属性和值的构造函数参数?

一个例子是能够从Required属性ErrorMessage获取:名称和ErrorMessage。值

获取属性的参数和值

可以使用MemberInfo.NameTypedValue.Value。下面是代码:

foreach (var propertyInfo in typeof(YOUR CLASS).GetProperties())
{
    var attr = propertyInfo.GetCustomAttributesData();
    foreach (var customAttributeData in attr)
    {
        foreach (var item in customAttributeData.NamedArguments)
        {
            var name = item.MemberInfo.Name;
            var value = item.TypedValue.Value;
        }
    }
}

您需要进一步使用反射,对每个属性使用Type.GetProperties,然后使用PropertyInfo.GetValue提取每个属性公开暴露的属性值。

尝试一次查找一种类型的属性:

foreach (var reqAttr in (RequiredAttribute[])propertyInfo.GetCustomAttributes(typeof(RequiredAttribute), false))
{
    // use reqAttr.ErrorMessage and so on, in here
}