Question

I have a main parent winform in which I have implemented some features and that have a number of child windows. Now I want the functionality I have implemented to run also on the child windows.

For instance, in the parent window I am moving an image on the selection of a checkbox. Now, if this checkbox is checked then the image should also move on the all other child windows.

Note: The image moving on the parent window should disapper and should only show on the opend dialogue or child window.

Please suggest if it is possible.

Answer 1

Try using events.

Create an event for the parent form called ImageMoved.

The child forms should subscribe to this event, and when you move the image, you raise the event, then the child forms will know to do their thing.

Lots of different ways to do this. Simple example:

public partial class Form1 : Form {
  public event EventHandler ImageMoved;

  private void OnImageMoved() {
    if (ImageMoved != null)
      ImageMoved(this, new EventArgs());
  }

  private void button1_Click(object sender, EventArgs e) {
    OnImageMoved();
  }

  private void button2_Click(object sender, EventArgs e) {
    Form2 f2 = new Form2(this);
    f2.Show();
  }
}

Then your child forms could look something like this:

public partial class Form2 : Form {
  public Form2(Form1 parentForm) {
    InitializeComponent();
    parentForm.ImageMoved += new EventHandler(parentForm_ImageMoved);
  }

  void parentForm_ImageMoved(object sender, EventArgs e) {
    MessageBox.Show("Image moved");
  }
}

You could also create your own EventArgs class if you want to pass more information, such as which image, etc.