ContextMenuStrip.SourceControl 属性

定义

命名空间:

System.Windows.Forms

程序集:

System.Windows.Forms.dll

Source:

ContextMenuStrip.cs

获取上一个使此 ContextMenuStrip 被显示的控件。

C#

[System.ComponentModel.Browsable(false)]
public System.Windows.Forms.Control? SourceControl { get; }

属性值

Control

使此 ContextMenuStrip 被显示的控件。

属性

BrowsableAttribute

示例

下面的代码示例演示了对事件的重用和处理的Opening动态SourceControl确定。 此示例是为 类提供的更大示例的 ContextMenuStrip 一部分。

C#

// This event handler is invoked when the ContextMenuStrip
// control's Opening event is raised. It demonstrates
// dynamic item addition and dynamic SourceControl 
// determination with reuse.
void cms_Opening(object sender, System.ComponentModel.CancelEventArgs e)
{
    // Acquire references to the owning control and item.
    Control c = fruitContextMenuStrip.SourceControl as Control;
    ToolStripDropDownItem tsi = fruitContextMenuStrip.OwnerItem as ToolStripDropDownItem;

    // Clear the ContextMenuStrip control's Items collection.
    fruitContextMenuStrip.Items.Clear();

    // Check the source control first.
    if (c != null)
    {
        // Add custom item (Form)
        fruitContextMenuStrip.Items.Add("Source: " + c.GetType().ToString());
    }
    else if (tsi != null)
    {
        // Add custom item (ToolStripDropDownButton or ToolStripMenuItem)
        fruitContextMenuStrip.Items.Add("Source: " + tsi.GetType().ToString());
    }

    // Populate the ContextMenuStrip control with its default items.
    fruitContextMenuStrip.Items.Add("-");
    fruitContextMenuStrip.Items.Add("Apples");
    fruitContextMenuStrip.Items.Add("Oranges");
    fruitContextMenuStrip.Items.Add("Pears");

    // Set Cancel to false. 
    // It is optimized to true based on empty entry.
    e.Cancel = false;
}

注解

属性的 SourceControl 常见用途包括：

• 在事件期间 Opening 添加、删除、启用或禁用菜单项。

• 基于上次显示 ContextMenuStrip的 控件，决定修改所选命令。

适用于