C# 編寫菜單的使用問題講解

1、源代碼
private void toolStripMenuItem1_Click(object sender, EventArgs e)
{   
        //點擊展開(關閉)其他項鈕的事件
        switch  (i)
        {
                case 1:
                this.設置密碼ToolStripMenuItem.Visible = false;
                this.添加用戶ToolStripMenuItem.Visible = false;
                this.忘記密碼ToolStripMenuItem.Visible = false;
                this.修改密碼ToolStripMenuItem.Visible = false;
                this.員工錄入ToolStripMenuItem.Visible = false;
                i = 2;
                this.操作ToolStripMenuItem.ShowDropDown();
                break;
                
                case 2:
                this.設置密碼ToolStripMenuItem.Visible = true;
                this.添加用戶ToolStripMenuItem.Visible = true;
                this.忘記密碼ToolStripMenuItem.Visible = true;
                this.修改密碼ToolStripMenuItem.Visible = true;
                this.員工錄入ToolStripMenuItem.Visible = true;
                i = 1;
                this.操作ToolStripMenuItem.ShowDropDown();
                break;
        }
}

2、如果只是初始窗體時，控制菜單的是否可見，只要設置菜單項的Visible屬性即可、

3、此處特殊點是this.操作ToolStripMenuItem.ShowDropDown();
無此句時，點擊後系統自動關閉菜單，認為是執行按鈕事件後結束，菜單刷新了看不見，需要點擊菜單才能觀察；加入此句後，菜單更新並且不關閉，用戶可以直接看到菜單的變化。