How to copy one Graphics Object into another

问题

I am trying to copy the contents of one graphics object to another, but the only was I have been able to find is based on using GDI32.DLL, which i would rather avoid using if possible.

Does anyone know how/if this is possible using managed code? I don't mind if answers are in C# or VB.Net.

Here is what I currently have:

Private Sub CopyGraphics()
    Dim srcPic As Graphics = pnl.CreateGraphics

    Dim srcBmp As New Bitmap(pnl.Width, pnl.Height, srcPic)
    Dim srcMem As Graphics = Graphics.FromImage(srcBmp)

    Dim HDC1 As IntPtr = srcPic.GetHdc
    Dim HDC2 As IntPtr = srcMem.GetHdc

    BitBlt(HDC2, 0, 0, pnl.Width, pnl.Height, HDC1, 0, 0, 13369376)

    pnlDraw.BackgroundImage = srcBmp

    'Clean Up code omitted...
End Sub

回答1:

Strictly speaking, it's not possible to copy the contents of a Graphics object anywhere using any method, because a Graphics object doesn't contain anything.

Why don't use the DrawToBitmap method to draw the control on the bitmap?

Dim srcBmp As New Bitmap(pnl.Width, pnl.Height)
Dim clip As New Rectangle(New Point(0, 0), pnl.Size)
pnl.DrawToBitmap(srcBmp, clip)

来源：https://stackoverflow.com/questions/597037/how-to-copy-one-graphics-object-into-another