Is it possible to store string values in dictionary object with comma seperated in c# out of a list

I need to convert list into dictionary based on key. I have list a like as below id, name and so on in List object List items.

List<MyData> lst = new List<MyData>();

MyData objMyData = new MyData();
MyData objMyData1 = new MyData();
MyData objMyData2 = new MyData();
objMyData.Id = 1;
objMyData.Name = "Test";
lst.Add(objMyData);
objMyData1.Id = 2;
objMyData1.Name = "Test2";
lst.Add(objMyData1);
objMyData2.Id = 1;
objMyData2.Name = "Test3";
lst.Add(objMyData2);

As per my requirement I need to create a dictionary object from it in this format.

Dictionary<int, string>.
Where key is int id of item and value in string of item.name with comma seperated one. it should look like

Dictionary<1, "Test, test3")
Dictionary<2, "Test2")

I’m trying below code, but stuck.

var dict = lst.ToLookup(x => x.Id)
.ToDictionary(x => x.Key, x=>x.ToList());

here instead of x.ToList(), my requirement is to get list.name with comma separated based on key.

>Solution :

.ToList() will return the grouped list of MyData.

You should select the Name and combine it into a string.

var dict = lst.ToLookup(x => x.Id)
    .ToDictionary(x => x.Key, x => String.Join(",", x.Select(y => y.Name)));