窗口置前

using System.Runtime.InteropServices;
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		[DllImport("user32.dll")]
		public static extern bool SetWindowPos(IntPtr hWnd,IntPtr hPos,int x,int y,int cx,int cy,uint nflags);
			
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IntPtr HWND_TOPMOST = new IntPtr(-1);
			uint SWP_NOSIZE = 0x0001;
			uint SWP_NOMOVE = 0x0002;
			SetWindowPos(handle,HWND_TOPMOST,0,0,0,0,SWP_NOSIZE|SWP_NOMOVE);