Today I wanted to create a transparent Panel-Control in .NET in order to superimpose it on the WebBrowser Control in order to record click events. The goal was to code a simple macro recorder for websites. Unfortunatelly the .NET framework does not allow (in an easy way) to make a control fully transparent. So it was back to the good ol' winuser.h and the extended window styles. Namely 0x00000020L or as it is better known WS_EX_TRANSPARENT.