private ManualResetEvent manualReset = new ManualResetEvent(true);

        private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
        {
            manualReset.WaitOne();

//下面是一些需要执行的操作
}

  private void Form1_KeyDown(object sender, KeyEventArgs e)
        {


            // 组合键
            if (e.KeyCode == Keys.Z && e.Modifiers == Keys.Control)
            {

                manualReset.Reset();
              

            }
            else if (e.KeyCode == Keys.X && e.Modifiers == Keys.Control)
            {
                manualReset.Set();
            }
        }