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Create a new instance of the anonymous type

I am trying to create an instance of an anonymous type:

new { Channel = g.Key.Channel, Comment = g.Key.Comment, Count = g.Count() }

In .NET, the darkness creates an anonymous type with a constructor that takes three arguments: String, String, Int32.

To create a new instance of this anonymous type, T, I do:

object[] args = new object[3];
args[0] = "arg1";
args[1] = "arg2";
args[2] = 200;
(T)Activator.CreateInstance(typeof(T), args);

.NET unloads me:

Additional Information: Constructor not found in '<> f__AnonymousType2`3 [[System.String, ...], [System.String, ...], [System.Int32, ...]]'.

I don’t know why CreateInstancetrying to call a constructor like [[], [], []]!

Region

The actual volume is a little harder to explain:

I created a Linq provider. This provider translates Linq suggestions to my server methods. When I get json information, I need to project this information depending on which Type user specified. In this case:

var enumerable = UIContainer.UIController.Instance.getDigitalInputs()
    .GroupBy(di => new { Channel = di.Channel, Comment = di.Comment })
    .Select(g => new { Channel = g.Key.Channel, Comment = g.Key.Comment, Count = g.Count() });

, json new { Channel = g.Key.Channel, Comment = g.Key.Comment, Count = g.Count() }). .

:

// make the HTTP request
IRestResponse response = (IRestResponse) this.client.CallApi(path, Method.GET, queryParams, postBody, headerParams, formParams, fileParams, authSettings);

if (((int)response.StatusCode) >= 400) {
    throw new ApiException (response.StatusCode, "Error calling Search: " + response.Content, response.Content);
}

Newtonsoft.Json.Linq.JArray feeds = Newtonsoft.Json.Linq.JArray.Parse(response.Content);
if (feeds.Any())
{
     PropertyDescriptorCollection dynamicProperties = TypeDescriptor.GetProperties(feeds.First());
     foreach (dynamic feed in feeds)
     {
         object[] args = new object[dynamicProperties.Count];
         int i = 0;
         foreach (PropertyDescriptor prop in dynamicProperties)
         {
             args[i++] = prop.GetValue(feed);
         }
         //args[0] = "";
         //args[1] = "";
         //args[2] = 2;

         yield return (T)Activator.CreateInstance(typeof(T), args);
    }
}
+4
1

, T, , :

var x = new { Channel = "Channel", Comment = "Comment", Count = 1 };

object[] args = new object[3];
args[0] = "arg1";
args[1] = "arg2";
args[2] = 200;
var y = Activator.CreateInstance(x.GetType(), args);

( Luaan:.NET , . IL:)

.method public hidebysig specialname rtspecialname 
        instance void  .ctor(!'<Channel>j__TPar' Channel,
                             !'<Comment>j__TPar' Comment,
                             !'<Count>j__TPar' Count) cil managed
+1

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