I hate to tell you this, but you cannot do what you want to do with the standard controls in the ToolBox. Transparent is not really transparent. When you set the BackColor of a control to Transparent, you're really telling the control to take on the background properties of the controls parent container. You will NOT be able to see any controls sitting behind the DGV. You cannot achieve what you want without custom drawing the DGV. That's not something that I want to think about, let alone do. I think your best shot at success with this would be to implement this in a WPF app, not Windows Forms.
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Dave Kreskowiak Microsoft MVP Visual Developer - Visual Basic
2006, 2007, 2008
But no longer in 2009...