30

我有一个 ListBox，我想为列表中的每个项目添加一个上下文菜单。我已经看到了“解决方案”让右键单击选择一个项目并在空白处抑制上下文菜单，但是这个解决方案感觉很脏。

有谁知道更好的方法？

4

10 回答 10

29

只是为了进一步详细说明 Frans 所说的内容......即使 ListBox 拥有 ContextMenuStrip，您仍然可以在菜单条打开时自定义菜单条中的项目。因此，根据列表框中的鼠标位置自定义其内容。

下面的示例基于鼠标右键单击选择列表框中的项目，然后根据用户右键单击的项目自定义上下文菜单条。这是一个简单的示例，但应该可以帮助您：将列表框添加到表单并添加以下代码：

#region Private Members
private ContextMenuStrip listboxContextMenu;
#endregion

private void Form1_Load( object sender, EventArgs e )
{
    //assign a contextmenustrip
    listboxContextMenu = new ContextMenuStrip();
    listboxContextMenu.Opening +=new CancelEventHandler(listboxContextMenu_Opening);
    listBox1.ContextMenuStrip = listboxContextMenu;

    //load a listbox
    for ( int i = 0; i < 100; i++ )
    {
        listBox1.Items.Add( "Item: " + i );
    }
}

private void listBox1_MouseDown( object sender, MouseEventArgs e )
{
    if ( e.Button == MouseButtons.Right )
    {
        //select the item under the mouse pointer
        listBox1.SelectedIndex = listBox1.IndexFromPoint( e.Location );
        if ( listBox1.SelectedIndex != -1)
        {
            listboxContextMenu.Show();   
        }                
    }
}

private void listboxContextMenu_Opening( object sender, CancelEventArgs e )
{
    //clear the menu and add custom items
    listboxContextMenu.Items.Clear();
    listboxContextMenu.Items.Add( string.Format( "Edit - {0}", listBox1.SelectedItem.ToString() ) );
}

希望有所帮助。

于 2008-12-18T14:45:25.390 回答
6

这样菜单会在鼠标旁边弹出

private string _selectedMenuItem;
private readonly ContextMenuStrip collectionRoundMenuStrip;

public Form1()
{ 
    var toolStripMenuItem1 = new ToolStripMenuItem {Text = "Copy CR Name"};
    toolStripMenuItem1.Click += toolStripMenuItem1_Click;
    var toolStripMenuItem2 = new ToolStripMenuItem {Text = "Get information on CR"};
    toolStripMenuItem2.Click += toolStripMenuItem2_Click;
    collectionRoundMenuStrip = new ContextMenuStrip();
    collectionRoundMenuStrip.Items.AddRange(new ToolStripItem[] {toolStripMenuItem1, toolStripMenuItem2 });
    listBoxCollectionRounds.MouseDown += listBoxCollectionRounds_MouseDown;
}

private void toolStripMenuItem2_Click(object sender, EventArgs e)
{
    var info = GetInfoByName(_selectedMenuItem);
   MessageBox.Show(info.Name + Environment.NewLine + info.Date);
}

private void toolStripMenuItem1_Click(object sender, EventArgs e)
{
    Clipboard.SetText(_selectedMenuItem);
}

private void myListBox_MouseDown(object sender, MouseEventArgs e)
{
    if (e.Button != MouseButtons.Right) return;
    var index = myListBox.IndexFromPoint(e.Location);
    if (index != ListBox.NoMatches)
    {
        _selectedMenuItem = listBoxCollectionRounds.Items[index].ToString();
        collectionRoundMenuStrip.Show(Cursor.Position);
        collectionRoundMenuStrip.Visible = true;
    }
    else
    {
        collectionRoundMenuStrip.Visible = false;
    }
}
于 2015-06-16T07:19:39.770 回答
4

没有其他办法：上下文菜单不属于列表框中的项目，而是属于列表框本身。它类似于树视图控件，它也拥有上下文菜单而不是树节点。所以每当列表框中的一个项目被选中时，根据选中的项目设置列表框的上下文菜单。

于 2008-12-18T08:14:21.717 回答
4

这是我的解决方案：

listBox_Usernames.ContextMenuStrip = contextMenuStripRemove;
listBox_Usernames.MouseUp += new MouseEventHandler(listBox_Usernames_MouseUp);

void listBox_Usernames_MouseUp(object sender, MouseEventArgs e)
{
    int index = listBox_Usernames.IndexFromPoint(e.Location);
    if (e.Button == System.Windows.Forms.MouseButtons.Right)
    {
        if (index != ListBox.NoMatches)
        {
            if (listBox_Usernames.SelectedIndex == index)
            {
                listBox_Usernames.ContextMenuStrip.Visible = true;
            }
            else
            {
                listBox_Usernames.ContextMenuStrip.Visible = false;
            }
        }
        else
        {
            listBox_Usernames.ContextMenuStrip.Visible = false;
        }
    }
    else
    {
        listBox_Usernames.ContextMenuStrip.Visible = false;
    }
}
于 2013-03-14T13:52:15.557 回答
2

在 XAML 中它显示如下：

<ListBox>
    <ListBox.ContextMenu>
        <ContextMenu>
            <MenuItem Header="Add User..."/>
            <MenuItem Header="Edit..."/>
            <MenuItem Header="Disable"/>
        </ContextMenu>
    </ListBox.ContextMenu>
</ListBox>
于 2011-12-07T15:05:12.613 回答
2

在一行代码中（更多用于绑定）：

var datasource = new BindingList<string>( new List<string>( new string[] { "item1" } ) );
listbox.DataSource = datasource ;
listbox.ContextMenu = new ContextMenu(
    new MenuItem[] { 
        new MenuItem("Delete", 
            new EventHandler( (s,ev) => 
            datasource.Remove(listbox.SelectedItem.ToString())
        )
    ) 
});

private void buttonAdd_Click(object sender, EventArgs e)
{
    datasource.Add( textBox.Text );
}
于 2016-08-09T10:17:44.873 回答
1

如果它只是启用或禁用上下文菜单项的问题，那么仅在启动上下文菜单而不是每次列表框选择更改时才这样做可能更有效：

myListBox.ContextMenu.Popup += new EventHandler(myContextPopupHandler);


private void myContextPopupHandler(Object sender, System.EventArgs e)
{
    if (SelectedItem != null)
    {
        ContextMenu.MenuItems[1].Enabled = true;
        ContextMenu.MenuItems[2].Enabled = true;
    }
    else
    {
        ContextMenu.MenuItems[1].Enabled = false;
        ContextMenu.MenuItems[2].Enabled = false;
    }
}
于 2009-08-29T00:02:59.513 回答
1

这个最好...

using System.Windows.Forms;

ContextMenuStrip menu;

this.menu.Items.AddRange(new ToolStripItem[] { this.menuItem });
this.listBox.MouseUp += new MouseEventHandler(this.mouse_RightClick);

private void mouse_RightClick(object sender, MouseEventArgs e)
{
    int index = this.listBox.IndexFromPoint(e.Location);
    if (index != ListBox.NoMatches)
    {
        menu.Visible = true;
    }
    else
    {
        menu.Visible = false;
    }
}
于 2012-06-19T12:36:43.260 回答
0 
//Create and Initialize the contextMenuStrip component
contextMenuStrip_ListaAulas = new ContextMenuStrip();

//Adding an Item
contextMenuStrip_ListaAulas.Items.Add("Modificar");

//Binding the contextMenuStrip with the ListBox
listBox_Aulas.ContextMenuStrip = contextMenuStrip_ListaAulas;

//The solution below 
if (e.Button == System.Windows.Forms.MouseButtons.Right)
{
    //select the item under the mouse pointer
    listBox_Aulas.SelectedIndex = listBox_Aulas.IndexFromPoint(e.Location);

    //if the selected index is an item, binding the context MenuStrip with the listBox
    if (listBox_Aulas.SelectedIndex != -1)
    {
         listBox_Aulas.ContextMenuStrip = contextMenuStrip_ListaAulas;  
    }
    //else, untie the contextMenuStrip to the listBox 
    else
    {
         listBox_Aulas.ContextMenuStrip = null;
    }
}
于 2012-12-27T15:24:07.230 回答
0

我确实喜欢这个，这对我来说效果很好而且速度很快。

private void contextMenuStrip1_Opening(object sender, CancelEventArgs e)
    {
        if (Listbox.SelectedItem == null)
            e.Cancel = true;
    }
于 2015-11-13T09:06:48.310 回答