How to change HwndSource window size C#

Question

I created a window as a child window of a C++ window handler in C#, the code is like:

public void CreateHostHwnd(IntPtr parentHwnd)
        {
            // Set up the parameters for the host hwnd.
            parentHandle = parentHwnd;
            HwndSourceParameters parameters = new HwndSourceParameters("Video Window", 351, 295);
            parameters.WindowStyle += WS_CHILD;
            parameters.SetPosition(0, 0);
            parameters.ParentWindow = parentHwnd;

            // Create the host hwnd for the visuals.
            HwndSource myHwndSource = new HwndSource(parameters);
        }

However, after this child window is created, I cannot change its size by using

parameters.SetSize(width, height);

Are there any way to change its size after it is created? Thank you~!