C#通過屬性名字符串獲取、設置對象屬性值

目錄

• #通過反射獲取對象屬性值並設置屬性值
  • 0、定義一個類
  • 1、通過屬性名（字符串）獲取對象屬性值
  • 2、通過屬性名（字符串）設置對象屬性值
• #獲取對象的所有屬性名稱及類型
• #判斷對象是否包含某個屬性

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#通過反射獲取對象屬性值並設置屬性值

0、定義一個類

    public class User
    { 
        public int Id { get; set; }
        public string Name { get; set; }
        public string Age { get; set; }
    }

1、通過屬性名（字符串）獲取對象屬性值

   User u = new User();
   u.Name = "lily";
   var propName = "Name";
   var propNameVal = u.GetType().GetProperty(propName).GetValue(u, null);
   
   Console.WriteLine(propNameVal);// "lily"

2、通過屬性名（字符串）設置對象屬性值

   User u = new User();
   u.Name = "lily";
   var propName = "Name";
   var newVal = "MeiMei";
   u.GetType().GetProperty(propName).SetValue(u, newVal);
   
   Console.WriteLine(propNameVal);// "MeiMei"

#獲取對象的所有屬性名稱及類型

• 通過類的對象實現

   User u = new User();

   foreach (var item in u.GetType().GetProperties())
   {
       Console.WriteLine($"propName:{item.Name},propType:{item.PropertyType.Name}");
   }
   // propName: Id,propType: Int32
   // propName:Name,propType: String
   // propName:Age,propType: String

• 通過類實現

   foreach (var item in typeof(User).GetProperties())
   {
       Console.WriteLine($"propName:{item.Name},propType:{item.PropertyType.Name}");
   }
   // propName: Id,propType: Int32
   // propName:Name,propType: String
   // propName:Age,propType: String

#判斷對象是否包含某個屬性

   static void Main(string[] args)
   {
       User u = new User();
       bool isContain= ContainProperty(u,"Name");// true
   }


   public static bool ContainProperty( object instance, string propertyName)
   {
       if (instance != null && !string.IsNullOrEmpty(propertyName))
       {
           PropertyInfo _findedPropertyInfo = instance.GetType().GetProperty(propertyName);
           return (_findedPropertyInfo != null);
       }
       return false;
   }

• 將其封裝為擴展方法

   public static class ExtendLibrary
   {
       /// <summary>
       /// 利用反射來判斷對象是否包含某個屬性
       /// </summary>
       /// <param name="instance">object</param>
       /// <param name="propertyName">需要判斷的屬性</param>
       /// <returns>是否包含</returns>
       public static bool ContainProperty(this object instance, string propertyName)
       {
           if (instance != null && !string.IsNullOrEmpty(propertyName))
           {
               PropertyInfo _findedPropertyInfo = instance.GetType().GetProperty(propertyName);
               return (_findedPropertyInfo != null);
           }
           return false;
       }
   }

   static void Main(string[] args)
   {
       User u = new User();
       bool isContain= u.ContainProperty("Name");// true
   }

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