为什么关闭嵌套子对话框也会关闭父对话框？

Question

我使用ShowDialog打开一个表单作为模态对话框.此对话框允许使用ShowDialog再次打开另一个窗体作为模式对话框.

当最里面的对话框关闭时,这也会导致其父对话框关闭.为什么会发生这种情况,我该如何预防呢？

我已经创建了问题的hello world版本来说明这一点.

表格1:

private void OpenForm2Button_Click(object sender, EventArgs e)
{
    Form2 testForm = new Form2();
    DialogResult dialogResult = new DialogResult();
    dialogResult = testForm.ShowDialog();
    MessageBox.Show("Form 2 returned: " + Convert.ToString(dialogResult));
}

表格2:

...
this.Form2OKButton.DialogResult = System.Windows.Forms.DialogResult.OK;
this.Form2CancelButton.DialogResult = System.Windows.Forms.DialogResult.Cancel;
...
this.AcceptButton = this.Form2OKButton;
this.CancelButton = this.Form2CancelButton;
...
private void OpenForm3Button_Click(object sender, EventArgs e)
{
    Form3 testForm = new Form3();
    DialogResult dialogResult = new DialogResult();
    dialogResult = testForm.ShowDialog();
    MessageBox.Show("Form 3 returned: " + Convert.ToString(dialogResult));
}

表格3:

...
this.Form3OKButton.DialogResult = System.Windows.Forms.DialogResult.OK;
this.Form3CancelButton.DialogResult = System.Windows.Forms.DialogResult.Cancel;
...
this.AcceptButton = this.Form3OKButton;
this.CancelButton = this.Form3CancelButton;

重现步骤:

• 点击"打开表单2"
• 点击"打开表单3"
• 点击"取消"

表格3以DialogResult ==取消按预期结束,但表格2也以DialogResult ==取消(不是预期)结束.

Answer 1

编辑:

问题是这一个(文件:) Form2.Designer.cs:

this.OpenForm3Button.DialogResult = System.Windows.Forms.DialogResult.Cancel;

当您OpenForm3Button在OpenForm3Button_Click事件处理程序结束后单击时,form.DialogResult会自动设置为Cancel并关闭它.

重置DialogResult属性,OpenForm3Button它将按预期工作:)