Question: I would like to ask,

I have a window called `MainWindow` and another one called `ImportForm`.
In the `MainWindow` i call

```
private void generate_Window(int num_chart) 
{ 
    Window ownedWindow = new ImportForm(num_chart); 
    ownedWindow.Owner = this;      
    ownedWindow.Show(); 
}

```

In the child window i make some stuff and i produce some variables. like var1,var2,var3.

I want when the child window close to return `var1`,`var2`,`var3` to the `MainWindow` and call one function let's say `import_chart(var1, var2, var3)`..

Any help will be apretiated.
Thanks

Answer: 
It seems like an awkward design choice. Anyways, here is how you can do it:

MainWindow.cs:

```
private void generate_Window(int num_chart)
{
    Window ownedWindow = new ImportForm(num_chart, import_chart); 
    ownedWindow.Owner = this; 
    ownedWindow.Show();
}

private void import_chart(int n, string s, bool b)
{
    //Do something
}

```

ImportForm.cs:

```
private Action<int, string, bool> callback;
public ImportForm(int num_chart, Action<int, string, bool> action)
{
    InitializeComponent();
    Closed += ImportForm_Closed;
    callback = action;
}

private void ImportForm_Closed(object sender, EventArgs e)
{
    callback(0, "Test", false);
}

```

Just change the Action to the parameter types you need (and adjust ImportForm\_Closed(...) to use them as well).

If anything is unclear, let me know.
I have an example from my own code. It's generic and obvious enough that I can share it here.

I've done something along these lines.

```
    /// <summary>
    /// Show an InputBox similar to the pre-.NET InputBox functionality. Returns the original value when Cancel was pressed.
    /// </summary>
    /// <param name="OriginalValue">Pre-populated value in the input box</param>
    /// <param name="PromptText">Prompt text displayed on the form</param>
    /// <param name="Caption">Window caption</param>
    /// <returns>InputBoxResult structure containing both the DialogResult and the input text. Warning: The input text will always be returned regardless of the DialogResult, so don't use it if the DialogResult is Cancel.</returns>
    public static InputBoxResult Show(string OriginalValue = "", string PromptText = "", string Caption = "") {
        InputBox form = new InputBox {
           Text = Caption,
            lblPrompt = {Text = PromptText}, 
            txtInput = {Text = OriginalValue}
        };

        InputBoxResult res = new InputBoxResult();
        res.Result = form.ShowDialog();
        res.Input = form.txtInput.Text;

        return res;
    }

```

I created a class called InputBoxResult like this:

```
    /// <summary>
    /// Represents the results from an InputBox.Show call, including the DialogResult
    /// and the input data. Note that the input data is always populated with the
    /// user-entered data regardless of the DialogResult - this is inconsistent with
    /// the old InputBox behavior and may change in the future.
    /// </summary>
    public struct InputBoxResult {
        /// <summary>
        /// Describes the way the dialog was resolved (OK / Cancel)
        /// </summary>
        public DialogResult Result { get; set; }
        /// <summary>
        /// User-entered text
        /// </summary>
        public string Input { get; set; }

        /// <summary>
        /// Translate this result into a string for easy debugging
        /// </summary>
        /// <returns></returns>
        public override string ToString() {
            return "Result: " + Result.ToString() +
                "\r\nInput: " + Input.ToString();
        }
    }

```