问题 ContextMenuStrip.Owner属性null从嵌套ToolStripMenuItem检索时

我有一个 ContextMenuStrip 设置两个 ToolStripItem秒。第二 ToolStripItem 有两个额外的嵌套 ToolStripItem秒。我将其定义为：

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";

然后，我为三者的点击事件设置了一个事件监听器 ToolStripMenuItem那是我想回应的。以下是方法（我只列出了三种方法中的两种）：

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 displaying this context menu 
            DataGridView dgv = owner.SourceControl as DataGridView;
            if (dgv != null)
                // DO WORK
        }
    } 
}

void contextJumpToHeatmapStart_Click(object sender, EventArgs e)
{
    // Try to cast the sender to a ToolStripItem 
    ToolStripMenuItem menuItem = sender as ToolStripMenuItem;
    if (menuItem != null)
    {
        // Retrieve the ToolStripItem that owns this ToolStripItem 
        ToolStripMenuItem ownerItem = menuItem.OwnerItem as ToolStripMenuItem;
        if (ownerItem != null)
        {
            // Retrieve the ContextMenuStrip that owns this ToolStripItem 
            ContextMenuStrip owner = ownerItem.Owner as ContextMenuStrip;
            if (owner != null)
            {
                // Get the control that is displaying this context menu 
                DataGridView dgv = owner.SourceControl as DataGridView;
                if (dgv != null)
                    // DO WORK
            }
        }
    }
}

这是我的问题：

我的 contextJumpTo_Click 方法非常好。我们一直到我确定的地方 DataGridView 点击来自，我可以继续。该 contextJumpTo ToolStripMenuItem 但是，它不是一个嵌套的菜单项 ContextMenuStrip。

但我的方法 contextJumpToHeatmapStart_Click 不能正常工作。当我走到我确定的路线时 owner.SourceControl， SourceControl 是null，我无法继续。现在我知道了 ToolStripMenuItem 嵌套在我的另一个下面 ContextMenuStrip，但为什么呢 SourceControl 属性突然出现在我身上 ContextMenuStrip？

我如何获得 SourceControl 对于嵌套 ToolStripMenuItem 为一个 ContextMenuStrip？

我相信这是一个错误。

我试图抓取工具条父项列表以获取ContextStripMenu所有者，该工作正常，但SourceControl属性始终为null。

看起来常见的工作是在上下文菜单的开头设置控件：

private Control menuSource;

cms.Opening += cms_Opening;

void cms_Opening(object sender, CancelEventArgs e) {
  menuSource = ((ContextMenuStrip)sender).SourceControl;
}

然后你的代码基本上变成了这个：

DataGridView dgv = menuSource as DataGridView;
if (dgv != null) {
  // do work
}

我相信这是一个错误。

我试图抓取工具条父项列表以获取ContextStripMenu所有者，该工作正常，但SourceControl属性始终为null。

看起来常见的工作是在上下文菜单的开头设置控件：

private Control menuSource;

cms.Opening += cms_Opening;

void cms_Opening(object sender, CancelEventArgs e) {
  menuSource = ((ContextMenuStrip)sender).SourceControl;
}

然后你的代码基本上变成了这个：

DataGridView dgv = menuSource as DataGridView;
if (dgv != null) {
  // do work
}

问题 ContextMenuStrip.Owner属性null从嵌套ToolStripMenuItem检索时

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