ComboBox.SelectedIndexChanged 以编程方式更改索引时不会触发

Question

我正在使用 C#.net 中的 Windows 表单。我在表格上有 2 ComboBox 和 3 TextBox。当我更改 ComboBox1 中的值（通过与 UI 中的项目交互）时，它会更改 ComboBox2.

中的项目和选定项目

当 ComboBox2 的选定索引更改时，它应该更改所有 TextBox 中的文本，但似乎 SelectedIndexChanged 没有被解雇。

public void comboSelectionChanged(object sender, EventArgs e)
    {
        //when the selection changes...
        // 1) cast the sender as a comboBox
        ComboBox cBox = (ComboBox)sender;

        // 2) identify the sender
        if (cBox.Name.ToString() == "ComboBox1")
        {   //this is the 1st combo box                

            //load the children of the new selection into the form
            //child of ComboBox1 is ComboBox2
            ComboBox2.Items.Clear();
            ComboBox2.Text = null;
            string selected = null;

            foreach (string item in {"box2_item1","box2_item2"})
            {
                ComboBox2.Items.Add(item);
            }
            //need to set the selection last, because this will (hopefully) fire the selection changed event on the child

            if (selected != null)
            {//here I am actually getting the selected item from XML
                ComboBox2.SelectedItem = selected;
            }
            else
            {//this should be action that is initiated, which should definitely change the selected index
                ComboBox2.SelectedIndex = -1;
            }
        }
        else if (cBox.Name.ToString() == "ComboBox2")
        {   //this is the 2nd combobox              

            //load the children of the new selection into the form
            //the textBoxes are the children
            TextBox1.Text = "some new text that I am getting from XML";
            TextBox2.Text = "some other new text as above.";
            TextBox3.Text = "same thing, one more time" ;
        }
        else
        {   //I messed something up, because the combobox name is invalid
            Debug.Write("Unreachable code encountered: The combobox name {" + cBox.Name.ToString() + "} is not valid!");
            return;
        }

我已尝试对此进行简化，希望我没有过度简化它。如前所述，我从 XML 文件获取数据， 理想情况下 目标是使用此表单读取和写入 XML 文件。在我看来，所有 XML 都工作正常，因此我将其全部省略。

两个盒子的 SelectedIndexChanged 事件都与上面的代码相关联。当我更改 ComboBox1 的值时会发生什么，ComboBox2 的值也会更改，并且清除所选项目，但永远不会触发 ComboBox2.SeletedIndexChanged 事件（断点向我展示了代码时钟永远不会重新输入），因此 TextBox 的 none 会用新数据更新。

我希望一切都是有道理的，希望有人能帮助我找出我做错了什么。

Answer 1

事件处理程序只是一个方法，因此您可以直接调用它。如果你的处理程序被命名为 ComboBox2_SelectedIndexChanged 你可以这样做：

        ...
        else
        {//this should be action that is initiated, which should definitely change the selected index
            ComboBox2.SelectedIndex = -1;
            ComboBox2_SelectedIndexChanged(ComboBox2, new EventArgs());
        }
        ...

Answer 2

通过调用

在 [=11th=] 方法中自行触发 SelectedIndexChanged 事件

ComboBox2_SelectedIndexChanged(ComboBox2, new EventArgs());

ComboBox.SelectedIndexChanged 以编程方式更改索引时不会触发

ComboBox.SelectedIndexChanged does not fire when programatically changing the index

c#

combobox

selectedindexchanged

winforms