Delphi Programming Control Wallpaper

Controlling windows ' desktop wallpaper is a common feature of some diagram tools, it is very easy to implement this function, the following program makes the wallpaper for the picture we want, if the Thepchar is empty, then cancel the wallpaper, change to win default color; But this method is only temporary, After Windows restarts or restores the original bitmap, it is necessary to overwrite the Win.ini file for permanent retention in order to save the images that we have changed from being replaced. But this temporary is also good for us to realize the timing of the desktop picture function:

var THEPCHAR:pchar;
begin
THEPCHAR:=e:\a.jpg;
SystemParametersInfo(SPI_SETDESKWALLPAPER, 0, THEPCHAR, SPIF_SENDWININICHANGE)
end;