动态添加属性到 ExpandoObject

Question

我想在运行时动态地将属性添加到 ExpandoObject。因此，例如要添加一个字符串属性调用 NewProp 我想写类似这样的内容

var x = new ExpandoObject();
x.AddProperty("NewProp", System.String);

这很容易实现吗？

Answer 1

dynamic x = new ExpandoObject();
x.NewProp = string.Empty;

或者：

var x = new ExpandoObject() as IDictionary<string, Object>;
x.Add("NewProp", string.Empty);

Answer 2

正如 Filip 所解释的 - http://www.filipekberg.se/2011/10/02/adding-properties-and-methods-to-an-expandoobject-dynamicly/

您也可以在运行时添加方法。

var x = new ExpandoObject() as IDictionary<string, Object>;
x.Add("Shout", new Action(() => { Console.WriteLine("Hellooo!!!"); }));
x.Shout();

Answer 3

下面是一个示例帮助程序类，它转换一个对象并返回一个包含给定对象的所有公共属性的 Expando。

public static class dynamicHelper
    {
        public static ExpandoObject convertToExpando(object obj)
        {
            //Get Properties Using Reflections
            BindingFlags flags = BindingFlags.Public | BindingFlags.Instance;
            PropertyInfo[] properties = obj.GetType().GetProperties(flags);

            //Add Them to a new Expando
            ExpandoObject expando = new ExpandoObject();
            foreach (PropertyInfo property in properties)
            {
                AddProperty(expando, property.Name, property.GetValue(obj));
            }

            return expando;
        }

        public static void AddProperty(ExpandoObject expando, string propertyName, object propertyValue)
        {
            //Take use of the IDictionary implementation
            var expandoDict = expando as IDictionary<String, object>;
            if (expandoDict.ContainsKey(propertyName))
                expandoDict[propertyName] = propertyValue;
            else
                expandoDict.Add(propertyName, propertyValue);
        }
    }

用法：

//Create Dynamic Object
dynamic expandoObj= dynamicHelper.convertToExpando(myObject);
    
//Add Custom Properties
dynamicHelper.AddProperty(expandoObj, "dynamicKey", "Some Value");

Answer 4

这是我找到的最好的解决方案。但要小心。使用异常处理，因为它可能不适用于所有情况

public static dynamic ToDynamic(this object obj)
{
    return JsonConvert.DeserializeObject<dynamic>(JsonConvert.SerializeObject(obj));
}

//您可能想要使用的另一个不错的扩展方法

    public static T JsonClone<T>(this T source)
    {
        if (!typeof(T).IsSerializable)
        {
            throw new ArgumentException("The type must be serializable.", nameof(source));
        }

        var serialized = JsonConvert.SerializeObject(source);
        return JsonConvert.DeserializeObject<T>(serialized);
    }