MouseLeave 检测不适用于 ImageForm

Question

我的表单中有一张较小的图片。当用户将鼠标悬停在图像上时，它会显示更大的图像视图（跟随鼠标，但与鼠标保持一定距离）。为了做到这一点，当光标悬停在图像上时，我生成了一个没有 FormBorderStyles 的表单。

我遇到的问题运行是第一个表单似乎不再检测到鼠标在表单激活后悬停或离开 PictureBox。表单也不跟随光标。

这是我得到的精简版：

C#

    bool formOpen = false;
    public Form1()
    {
        InitializeComponent();
    }

    private void Form1_Load(object sender, EventArgs e)
    {
        pictureBox1.MouseHover += pictureBox1_MouseHover;
        pictureBox1.MouseLeave +=pictureBox1_MouseLeave;
    }

    void pictureBox1_MouseHover(object sender, EventArgs e)
    {
        if (formOpen == false)
        {
            Form form = new Form();
            form.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None;
            form.BackColor = Color.Orchid;
            //Show the form
            form.Show();
            form.Name = "imageForm";
            this.AddOwnedForm(form);

            //Set event handler for when the mouse leaves the image area.
            //form.MouseLeave += form_MouseLeave;
            //Set the location of the form and size
            form.BackColor = Color.Black;
            form.Dock = DockStyle.Fill;
            form.Size = new Size(30, 30);
            form.BackgroundImageLayout = ImageLayout.Center;
            this.TopMost = true;
            formOpen = true;

            form.Location = new Point(Cursor.Position.X, Cursor.Position.Y);
        }
    }


    private void pictureBox1_MouseLeave(object sender, EventArgs e)
    {
        //MessageBox.Show("Worked");
    }
}

Answer 1

MouseHover = 当鼠标指针停留在控件上时发生。 (msdn)

改用 MouseMove。

Answer 2

MouseLeave（和其他事件）未被识别，因为弹出窗口 window 的打开，特别是 topmost=true 将焦点从原始表单及其 PictureBox.

它也没有移动，因为没有提供移动代码..

以下是一些可以使表单移动的更改：

您需要在 form1 级别
您需要在 MouseMove 活动中移动它

请注意，Hover 是一种仅限一次的事件类型。它只触发一次直到你离开控制..（注意：Setsu 已经从 Hover 切换到 Enter。这工作正常，但缺少之前的短暂延迟显示第二个表格。如果你想要那个，你可以切换回 Hover 或者你可以通过 Timer 来伪造悬停延迟，这是我经常做的。）

// class level variable 
Form form;

private void Form1_Load(object sender, EventArgs e)
{
    pictureBox1.MouseEnter += pictureBox1_MouseEnter;
    pictureBox1.MouseLeave +=pictureBox1_MouseLeave;
    pictureBox1.MouseMove += pictureBox1_MouseMove;  // here we move the form..
}

// .. with a little offset. The exact numbers depend on the cursor shape
void pictureBox1_MouseMove(object sender, MouseEventArgs e)
{
    if ((form != null) && form.Visible)
    {
        form.Location = new Point(Cursor.Position.X + 5, Cursor.Position.Y + 5);
    }
}

void pictureBox1_MouseEnter(object sender, EventArgs e)
{
    // we create it only once. Could also be done at startup!
    if (form == null)
    {
         form = new Form();
         form.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None;
         //form.BackColor = Color.Orchid;
         form.Name = "imageForm";
         this.AddOwnedForm(form);
         form.BackColor = Color.Black;
         form.Dock = DockStyle.Fill;
         form.Size = new Size(30, 30);
         form.BackgroundImageLayout = ImageLayout.Center;
         //this.TopMost = true;  // wrong! this will steal the focus!!
         form.ShowInTaskbar = false;
    }
    // later we only show and update it..
    form.Show();
    form.Location = new Point(Cursor.Position.X + 5, Cursor.Position.Y + 5);
    // we want the Focus to be on the main form!
    Focus();
}

private void pictureBox1_MouseLeave(object sender, EventArgs e)
{
    if (form!= null) form.Hide();
}

MouseLeave 检测不适用于 ImageForm

MouseLeave detection not working with ImageForm

c#

forms

cursor

mouseleave

mousehover