我想用一个字符串访问一个动态c#属性的值:

动态d = new {value1 = "some", value2 = "random", value3 = "value"};

如果我只有“value2”作为字符串,我如何才能得到d.value2(“random”)的值?在javascript中,我可以做d["value2"]来访问值("random"),但我不确定如何用c#和反射来做到这一点。我最接近的说法是:

“value2”d.GetType () . getproperty()……但我不知道如何从中获得实际价值。

一如既往,谢谢你的帮助!


当前回答

在。net core 3.1中,你可以这样尝试

d?.value2 , d?.value3

其他回答

public static object GetProperty(object target, string name)
{
    var site = System.Runtime.CompilerServices.CallSite<Func<System.Runtime.CompilerServices.CallSite, object, object>>.Create(Microsoft.CSharp.RuntimeBinder.Binder.GetMember(0, name, target.GetType(), new[]{Microsoft.CSharp.RuntimeBinder.CSharpArgumentInfo.Create(0,null)}));
    return site.Target(site, target);
}

添加对Microsoft.CSharp的引用。也适用于动态类型和私有属性和字段。

编辑:虽然这种方法是有效的,但是从Microsoft.VisualBasic.dll程序集中可以找到几乎快20倍的方法:

public static object GetProperty(object target, string name)
{
    return Microsoft.VisualBasic.CompilerServices.Versioned.CallByName(target, name, CallType.Get);
}

这是我得到一个动态的属性值的方法:

    public dynamic Post(dynamic value)
    {            
        try
        {
            if (value != null)
            {
                var valorCampos = "";

                foreach (Newtonsoft.Json.Linq.JProperty item in value)
                {
                    if (item.Name == "valorCampo")//property name
                        valorCampos = item.Value.ToString();
                }                                           

            }
        }
        catch (Exception ex)
        {

        }


    }

从动态文档中获取属性 当.GetType()返回null时,尝试这样做:

var keyValuePairs = ((System.Collections.Generic.IDictionary<string, object>)doc);
var val = keyValuePairs["propertyName"].ToObject<YourModel>;

一些解决方案不是工作的valuekind对象,我从一个json字符串获得的,也许是因为我没有一个具体的类型在我的代码,类似于对象,我将从json字符串获得,所以我是如何去做的

JsonElement myObject = System.Text.Json.JsonSerializer.Deserialize<JsonElement>(jsonStringRepresentationOfMyObject);

/*In this case I know that there is a property with 
the name Code, otherwise use TryGetProperty. This will 
still return a JsonElement*/

JsonElement propertyCode = myObject.GetProperty("Code");
        
/*Now with the JsonElement that represents the property, 
you can use several methods to retrieve the actual value, 
in this case I know that the value in the property is a string, 
so I use the GetString method on the object. If I knew the value 
was a double, then I would use the GetDouble() method on the object*/

string code = propertyCode.GetString();

这对我很有用

在。net core 3.1中,你可以这样尝试

d?.value2 , d?.value3