I have a ContextMenuStrip setup with two ToolStripItems. The second ToolStripItem has two additional nested ToolStripItems. I define this as:

ContextMenuStrip cms = new ContextMenuStrip();
ToolStripMenuItem contextJumpTo = new ToolStripMenuItem();
ToolStripMenuItem contextJumpToHeatmap = new ToolStripMenuItem();
ToolStripMenuItem contextJumpToHeatmapStart = new ToolStripMenuItem();
ToolStripMenuItem contextJumpToHeatmapLast = new ToolStripMenuItem();

cms.Items.AddRange(new ToolStripItem[] { contextJumpTo,
                                         contextJumpToHeatmap});
cms.Size = new System.Drawing.Size(176, 148);

contextJumpTo.Size = new System.Drawing.Size(175, 22);
contextJumpTo.Text = "Jump To (No Heatmapping)";

contextJumpToHeatmap.Size = new System.Drawing.Size(175, 22);
contextJumpToHeatmap.Text = "Jump To (With Heatmapping)";
contextJumpToHeatmap.DropDownItems.AddRange(new ToolStripItem[] { contextJumpToHeatmapStart, 
                                                                  contextJumpToHeatmapLast });

contextJumpToHeatmapStart.Size = new System.Drawing.Size(165, 22);
contextJumpToHeatmapStart.Text = "From Start of File";

contextJumpToHeatmapLast.Size = new System.Drawing.Size(165, 22);
contextJumpToHeatmapLast.Text = "From Last Data Point";

I then setup an event listener for the click events of the three ToolStripMenuItems that I want to respond to. Here are the methods (I only listed two of the three methods):

void contextJumpTo_Click(object sender, EventArgs e)
{
    // Try to cast the sender to a ToolStripItem 
    ToolStripMenuItem menuItem = sender as ToolStripMenuItem;
    if (menuItem != null)
    {
        // Retrieve the ContextMenuStrip that owns this ToolStripItem 
        ContextMenuStrip owner = menuItem.Owner as ContextMenuStrip;
        if (owner != null)
        {
            // Get the control that is displa
c# .net winforms contextmenustrip
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