Issue

Controls I have added to my .Net application are hidden, but are not matched in my OpenSpan solution.

Resolution

To make a hidden control within a .Net application accessible to OpenSpan, you must call the CreateHandle method of the control. CreateHandle is a protected method so you will need to invoke it using reflection. The following code invokes CreateHandle using reflection:

// Must specify Instance and NonPublic
MethodInfo info = typeof(Control).GetMethod(
    "CreateHandle", BindingFlags.Instance | BindingFlags.NonPublic);
info.Invoke(txtCreateHandle, new object[] {});

The public method, CreateControl, also states that it will force the creation of a window. However, CreateControl will not work if a control is not visible. The remarks sections states:

Attached is a sample executable that demonstrates this behavior. If you examine the form in Spy++ you will notice that no EDIT windows are created. If you click “Make Visible”, you will notice that one EDIT control is now created. This demonstrates that .NET waits until a control is visible to create the underlying EDIT window. If you click “Create Handle”, you will notice that one additional EDIT control is now created.