Question

我有一个父表单，其中包含1个方法来刷新名为 resetPanel（）的面板内容。我在父表单中也有一个按钮。如果单击该按钮，将打开一个新表单。我会做一些更改，然后点击保存。内容将保存在数据库中，子窗体将关闭。现在将显示父表单。

我想立即调用resetPanel（）方法，以便面板显示更新的值。我怎样才能做到这一点？

Answer 1

如果您的子表单是对话框，则只需检查表单的对话框结果：

// Do not forget to release resources acquired: 
// wrap IDisposable into using(..) {...}
using (Form myChildForm = new MyChildForm()) {
  //TODO: If you want to pass something from the main form to child one: do it

  // On any result save "Cancel" update the panel
  if (myChildForm.ShowDialog() != DialogResult.Cancel) 
    resetPanel();
}

如果您的孩子不对话，您可以将this作为参考传递给子表单：

  Form myChildForm = new MyChildForm(this);

  myChildForm.Show(); // <- Just show, not ShowDialog()

  ...

  private MyMainForm m_MainForm;

  public MyChildForm(MyMainForm form) {
    m_MainForm = form;
  }

  private void save() {
    //TODO: Save to database here

    // Main form update
    if (!Object.ReferenceEquals(null, m_MainForm))
      m_MainForm.resetPanel(); // <- resetPanel should be public or internal method
  }

  private saveButton_Click(object sender, EventArgs e) {
    save();
  }

Answer 2

关闭Form2后，您可以调用ResetPanel方法：

Form2 f2 = new Form2();
f2.ShowDialog();
resetPanel();  // <-- this will be executed when you close the second form

Answer 3

表示例如你的父表单名称如果表单Form1和子表单名称作为Form2转到ur子表单设计器页面将其更改为访问修饰符

以及您希望调用的方法

Form2 f2=new Form2();
f2.Show();
.//from here on you can write your concerned code

Answer 4

如果您的resetPanel方法正在进行数据库调用，那么您很可能会避免它。虽然这不会获得应用程序中其他用户正在更新的任何数据。只需根据您的需要修改我的另一个answer代码。这只是一个样本：

public class ParentForm : Form
{
    Button openButton = new Button();

    public ParentForm()
    {
        openButton.Click += openButton_Click;
    }

    void openButton_Click(object sender, EventArgs e)
    {
        ChildForm childForm = new ChildForm();
        childForm.OKButtonClick += childForm_OKButtonClick;
        childForm.ShowDialog();
    }

    void childForm_OKButtonClick(object sender, MyEventArgs e)
    {
        // Use properties from event args and set data in this form
    }

}

public class ChildForm : Form
{
    Button okButton = new Button();
    TextBox name = new TextBox();
    TextBox address = new TextBox();

    public event EventHandler<MyEventArgs> OKButtonClick;

    public ChildForm()
    {
        okButton.Click += okButton_Click;
    }

    void okButton_Click(object sender, EventArgs e)
    {
        try
        {
            bool saveSucceeded = false;

            // Try saving data here

            if (saveSucceeded)
            {
                if (OKButtonClick != null)
                {
                    MyEventArgs myEventArgs = new MyEventArgs();

                    // Just get updated data from screen and send it to another form
                    myEventArgs.Name = name.Text;
                    myEventArgs.Address = address.Text;

                    OKButtonClick(sender, myEventArgs);
                }

                Close();
            }
            else
            {
                MessageBox.Show("Data could not be saved.");
            }
        }
        catch (Exception ex)
        {
            // Perform proper exception handling
        }
    }
}

public class MyEventArgs : EventArgs
{
    public string Name
    {
        get;
        set;
    }

    public string Address
    {
        get;
        set;
    }
}

Answer 5

尝试将Save中的child Form按钮设置为DialogResult.Ok，然后将“保存”按钮设置为子表单的AcceptButton。然后测试结果是否是用户按下保存按钮。以编程方式它看起来像这样：

Form2 chidForm = new Form2();
childForm.btnSave.DialogResult = DialogResult.Ok
childForm.AcceptButton = childForm.btnSave
if (childForm.ShowDialog() == DialogResult.Ok)
{
  resetPanel();
}

现在，我假设Save中的Child Form按钮名为btnSave。

如何从C＃中的子表单调用父表单方法？

5 个答案: