使用PInvoke调用本机函数以设置前台窗口：

using System.Diagnostics;
using System.Runtime.InteropServices;

[DllImport("User32.dll")]
private static extern Int32 SetForegroundWindow(nint hWnd);

void YourMethod()
{
  Process p = ... // However you create your process
  SetForegroundWindow(p.MainWindowHandle);  // Set this process's main window as the foreground window
}