从另一个事件中取消 FormClosing 事件？

Question

学校项目要求我创建一个网络浏览器。在上下文菜单中，我有一个 "Exit" 按钮，它可以执行一系列操作，例如将数据上传到 SQL 数据库等。如果 "try" 块中出现错误，则 catch 块向用户询问是否要关闭。

在 "formclosing" 事件中，我已经从 "exit" 按钮连接了我已经存在的 "exit" 功能，这样如果用户按下红色 "X"（在window 屏幕）关闭表单将具有相同的效果。

问题在于，因为它是一个 "formclosing" 事件，即使用户通过 "Exit" 按钮在问题对话框中选择了 "no"，它也会关闭表单。

所以我的问题是如何从 "Exit" 按钮中取消 "formclosing" 请求？

P.S。请忽略 delete sql 命令等奇怪的东西，我们老师有一些奇怪的要求。假设这确实是请求的功能。

private void יציאהToolStripMenuItem_Click(object sender, EventArgs e)
{
    Favorite fav;
    SqlCommand delfav = new SqlCommand("DELETE FROM tblFavorites", conn);
    SqlCommand addfav = new SqlCommand("INSERT INTO tblFavorites VALUES (@title, @url)", conn);
    addfav.Parameters.Add("@title", SqlDbType.NVarChar, 100);
    addfav.Parameters.Add("@url", SqlDbType.NVarChar, 300);
    try
    {
        conn.Open();
        delfav.ExecuteNonQuery();
        for (int i=0; i<favorites.Items.Count; i++)
        {
            fav = (Favorite)favorites.Items[i];
            addfav.Parameters["@title"].Value = fav.getsettitle;
            addfav.Parameters["@url"].Value = fav.getseturl;
            addfav.ExecuteNonQuery();
        }
        Application.Exit();
    }
    catch
    {
        DialogResult dialogResult = MessageBox.Show("There was a problem loading your favorites to the database. Do you still wish to quit? \n (All changes to the favorites list will be lost)", "", MessageBoxButtons.YesNo);
        if (dialogResult == DialogResult.Yes)
        {
            Application.Exit();
        }
        else
        {
            //Cancel the formclosing event here!
        }
    }
    finally
    {
        conn.Close();
    }
}

private void Form1_FormClosing(object sender, FormClosingEventArgs e)
{
    יציאהToolStripMenuItem_Click(null, null);
}

Answer 1

您应该替换这两个事件处理程序的功能。你也应该使用 this.Close() 而不是 Application.Exit()

private void ToolStripMenuItem_Click(object sender, EventArgs e)
{
    this.Close();
}

private void Form1_FormClosing(object sender, FormClosingEventArgs e)
{
    // your code
    try
    {
        // your code
    }
    catch
    {
        DialogResult dialogResult = MessageBox.Show("There was a problem loading your favorites to the database. Do you still wish to quit? \n (All changes to the favorites list will be lost)", "", MessageBoxButtons.YesNo);
        if (dialogResult != DialogResult.Yes)
        {
            //Cancel the formclosing event here!
            e.Cancel = true;
        }
    }
    finally
    {
        conn.Close();
    }
}

从另一个事件中取消 FormClosing 事件？

FormClosing event cancel from within another event?

.net

c#

events

winforms

formclosing