首先程式有托盤圖示功能，再增加如下程式碼即可：

private void Form1_Shown(object sender, EventArgs e) //窗體第一次顯示時
        {
            this.Hide();    //隱藏視窗
        }

        private void Form1_VisibleChanged(object sender, EventArgs e)
        {
            //MessageBox.Show(this.Visible.ToString());
            if (this.ShowInTaskbar == false)
            {
                this.ShowInTaskbar = true;
            }
        }