C#：将相同类型的其他项目的空项目添加到 ComboBox

Question

I have the problem that there are binding errors in my custom combobox (it derivates from the ComboBox from Windows Controls). There is a property called AddNullItem which adds a ComboBoxItem with the Content Empty .

compositeCollection.Add(new ComboBoxItem() { Content = "Empty" });

The Problem is that if you bind to this ComboBox and the Null-Item is selected, a binding error occurs, because the ComboBoxItems are not of the same type.

How can I add a ComboBoxItem of the same type of all other items or is there a better solution?

My solution was following: compositeCollection.Add(Activator.CreateInstance(this.Items.GetType())); , but then occurs a XamlParseException.

Answer 1

Okay, I got the solution:

I created the instance of the IEnumerable Items, not the single item. I used following:

object obj = System.Runtime.Serialization.FormatterServices.GetUninitializedObject(t);