动态用户控件事件未执行C＃中的方法

Question

我正在努力弄清为什么我的用户控制事件没有执行。我在动态UserControl“ MainControl”中有一个动态UserControl“ MainMenu”。在MainMenu中，我有以下内容：public partial class MainMenu : UserControl{    public MainMenu()    {        InitializeComponent();        ///        ///Event Subscriptions        ///         this.LostFocus += this.MainMenu_LostFocus;    }    public void MainMenu_LostFocus(object sender, EventArgs e)    {        this.Visible = false;    }}在MainControl中：public partial class MainControl : UserControl{    private Custom_UI.MainMenu mainMenu = new Custom_UI.MainMenu();    public MainControl()    {        InitializeComponent();        mainMenu.Visible = false;        mainMenu.BringToFront();                    this.Controls.Add(mainMenu);        mainMenu.BringToFront();    }    private void menuButton1_Click(object sender, EventArgs e)    {        if (mainMenu.Visible)        {            mainMenu.Visible = false;                        }        else        {            mainMenu.Visible = true;            this.Focus();        }    }}最后是主要形式：public partial class Form1 : Form{    MainControl mainControl = new MainControl() {        Dock = DockStyle.Fill    };    public Form1()    {        InitializeComponent();        this.Controls.Add(mainControl);    }}因此，基本上，MainMenu_LostFocus当我单击表单上的其他位置时，不会调用该方法。我也尝试使用this.MouseLeave代替this.LostFocus。希望我已经足够清楚了，在此先感谢。

Answer 1

好的，以免尝试另一种改进的方法。原因是我们不想强迫我们处理添加到每个控件上的单击MainControl并强迫它获得焦点。只是笨拙。

我们还希望将整个代码封装在一个控件（MainMenu）中-不是“必须”，而是“一定要”

这是我的新主意：

 public partial class MainMenu : UserControl

    {

        //this class will be checking native windows messages, the one we're interested in is "MouseDown" with 0x0201 code 

        //(i won't be describing the whole stuff what is going inside: have that checked if you wish in documentation :)

        [SecurityPermission(SecurityAction.LinkDemand, Flags = SecurityPermissionFlag.UnmanagedCode)]

        public class TestMessageFilter : IMessageFilter

        {

            const int WM_MOUSEMOVE = 0x200;

            const int WM_LBUTTONDOWN = 0x0201;

            public event EventHandler MouseMoved;

            public event EventHandler MouseDown;

            public bool PreFilterMessage(ref Message m)

            {

                // Blocks all the messages relating to the left mouse button.

                if (m.Msg == WM_LBUTTONDOWN)

                {

                    MouseDown?.Invoke(this, new EventArgs());

                }

                return false;

            }

        }

        public MainMenu()

        {

            InitializeComponent();

            //use our class that checks Windows Messages, subscribe it's event

            var tmf = new TestMessageFilter();

            tmf.MouseDown += UserControl1_MouseDown;

            //and add our class to Application's messages filter.

            Application.AddMessageFilter(tmf);

            //use "ordinary" events to detect mouse enter/mouse leave over control

            this.MouseLeave += UserControl1_MouseLeave;

            this.MouseEnter += UserControl1_MouseEnter;

        }

        private void UserControl1_MouseDown(object sender, EventArgs e)

        {

            //if mouse is not over control make it's visible false

            if (mouseLeft)

            {

                this.Visible = false;

            }

        }

        //variable to save mouse state (if that is over the control, or left)

        private bool mouseLeft;

        private void UserControl1_MouseEnter(object sender, EventArgs e)

        {

            mouseLeft = false;

        }

        private void UserControl1_MouseLeave(object sender, EventArgs e)

        {

            mouseLeft = true;

        }

    }

希望这个解决方案会更好，更实用