如果你只想要一个特定的属性值，例如Display Attribute，你可以使用以下代码:

var pInfo = typeof(Book).GetProperty("Name")
                             .GetCustomAttribute<DisplayAttribute>();
var name = pInfo.Name;

我把它写进一个动态方法中，因为我在整个应用程序中使用了很多属性。方法:

public static dynamic GetAttribute(Type objectType, string propertyName, Type attrType)
    {
        //get the property
        var property = objectType.GetProperty(propertyName);

        //check for object relation
        return property.GetCustomAttributes().FirstOrDefault(x => x.GetType() == attrType);
    }

用法:

var objectRelAttr = GetAttribute(typeof(Person), "Country", typeof(ObjectRelationAttribute));

var displayNameAttr = GetAttribute(typeof(Product), "Category", typeof(DisplayNameAttribute));

希望这对大家有所帮助

如果你想获得具有自定义属性的属性，那么请尝试以下方法:

IEnumerable propertyInfos = properties.GetType().GetProperties();

PropertyInfo p = PropertyInfo。Where(x => x. getcustomattribute () != null);

我已经通过编写一个通用扩展属性属性助手解决了类似的问题:

using System;
using System.Linq;
using System.Linq.Expressions;
using System.Reflection;

public static class AttributeHelper
{
    public static TValue GetPropertyAttributeValue<T, TOut, TAttribute, TValue>(
        Expression<Func<T, TOut>> propertyExpression, 
        Func<TAttribute, TValue> valueSelector) 
        where TAttribute : Attribute
    {
        var expression = (MemberExpression) propertyExpression.Body;
        var propertyInfo = (PropertyInfo) expression.Member;
        var attr = propertyInfo.GetCustomAttributes(typeof(TAttribute), true).FirstOrDefault() as TAttribute;
        return attr != null ? valueSelector(attr) : default(TValue);
    }
}

用法:

var author = AttributeHelper.GetPropertyAttributeValue<Book, string, AuthorAttribute, string>(prop => prop.Name, attr => attr.Author);
// author = "AuthorName"

这里有一些静态方法，可以用来获取MaxLength或任何其他属性。

using System;
using System.Linq;
using System.Reflection;
using System.ComponentModel.DataAnnotations;
using System.Linq.Expressions;

public static class AttributeHelpers {

public static Int32 GetMaxLength<T>(Expression<Func<T,string>> propertyExpression) {
    return GetPropertyAttributeValue<T,string,MaxLengthAttribute,Int32>(propertyExpression,attr => attr.Length);
}

//Optional Extension method
public static Int32 GetMaxLength<T>(this T instance,Expression<Func<T,string>> propertyExpression) {
    return GetMaxLength<T>(propertyExpression);
}


//Required generic method to get any property attribute from any class
public static TValue GetPropertyAttributeValue<T, TOut, TAttribute, TValue>(Expression<Func<T,TOut>> propertyExpression,Func<TAttribute,TValue> valueSelector) where TAttribute : Attribute {
    var expression = (MemberExpression)propertyExpression.Body;
    var propertyInfo = (PropertyInfo)expression.Member;
    var attr = propertyInfo.GetCustomAttributes(typeof(TAttribute),true).FirstOrDefault() as TAttribute;

    if (attr==null) {
        throw new MissingMemberException(typeof(T).Name+"."+propertyInfo.Name,typeof(TAttribute).Name);
    }

    return valueSelector(attr);
}

}

使用静态方法…

var length = AttributeHelpers.GetMaxLength<Player>(x => x.PlayerName);

或者在实例上使用可选的扩展方法…

var player = new Player();
var length = player.GetMaxLength(x => x.PlayerName);

或者对任何其他属性使用完整的静态方法(例如StringLength)…

var length = AttributeHelpers.GetPropertyAttributeValue<Player,string,StringLengthAttribute,Int32>(prop => prop.PlayerName,attr => attr.MaximumLength);

受到Mikael Engver回答的启发。

使用typeof(Book). getproperties()获取PropertyInfo实例数组。然后对每个PropertyInfo使用GetCustomAttributes()来查看它们中是否有Author Attribute类型。如果有，您可以从属性信息中获得属性的名称，并从属性中获得属性值。

沿着这些行来扫描类型中具有特定属性类型的属性，并在字典中返回数据(注意，通过将类型传递到例程中，这可以变得更加动态):

public static Dictionary<string, string> GetAuthors()
{
    Dictionary<string, string> _dict = new Dictionary<string, string>();

    PropertyInfo[] props = typeof(Book).GetProperties();
    foreach (PropertyInfo prop in props)
    {
        object[] attrs = prop.GetCustomAttributes(true);
        foreach (object attr in attrs)
        {
            AuthorAttribute authAttr = attr as AuthorAttribute;
            if (authAttr != null)
            {
                string propName = prop.Name;
                string auth = authAttr.Name;

                _dict.Add(propName, auth);
            }
        }
    }

    return _dict;
}