以下是您可以通过它的示例

Here is the example you can go through it

public partial class Form1 : Form
{
    RadListBox listBox = new RadListBox();
    public Form1()
    {
        InitializeComponent();
        this.Controls.Add(listBox);
 
        listBox.DataSource = new string[] { "1", "2", "3" };
        RadContextMenu menu = new RadContextMenu();
        RadContextMenuManager mgr = new RadContextMenuManager();
        mgr.SetRadContextMenu(listBox, menu);
 
        menu.DropDownOpening += new System.ComponentModel.CancelEventHandler(menu_DropDownOpening);
    }
 
    void menu_DropDownOpening(object sender, System.ComponentModel.CancelEventArgs e)
    {
        RadContextMenu menu = (RadContextMenu)sender;
        menu.Items.Clear();
        RadElement elementAtPoint = this.listBox.ElementTree.GetElementAtPoint(this.listBox.ListBoxElement.PointFromScreen(Control.MousePosition));
        if (elementAtPoint is RadListBoxItem)
        {
            // Add menu options based on the item.
            menu.Items.Add(new RadMenuItem((elementAtPoint as RadListBoxItem).Text));
        }
    }
}