'Passing' a variable from a child form to the parent... How???

csharp Japan
  • 13 years ago
    So...  That's the gist of it.  I have my main form, Form1.  And it has a child form, Form2.

    Now, it doesn't matter in the slightest if Form2 is shown or not.  Or if it's even active.  I want it, at the appropriate time (there's a few instances where this would happen), to retrive some data from Form1, which are variables.

    I also want Form2, on the press of a button (easy part) to update the variables on Form1(THIS is the hard part), and then display those variables in the appropriate area (the other easy part)...

    It *SHOULD* be easy enough, I know.  But for whatever reason or another, I just can NOT find how to do this.  It's just ever so slightly beyond me...

    So any help would be nice, THANKS!!!

  • 13 years ago

    In your main form, pass an object via the child form's constructor (chartDataHandler in this example):

       private void btnPick_Click(object sender, EventArgs e)
                FormCostPicker formCostPicker = new FormCostPicker(chartDataHandler);
                formCostPicker.ShowInTaskbar = false;

                DialogResult r = formCostPicker.ShowDialog();

                if (r == DialogResult.OK)
                    tbCost.Text = chartDataHandler.selectedItem.ToString();              


    In your second form, pick up and use the object you passed in:

       public partial class FormCostPicker : Form
            public ChartDataHandler chartDataHandler;

            public FormCostPicker(ChartDataHandler chartDataHandler)
                this.chartDataHandler = chartDataHandler;

            private void btnOK_Click(object sender, EventArgs e)
                chartDataHandler.selectedItem = Item;

                DialogResult = DialogResult.OK;

    This could be tided up a little, but that should point you in the right direction.


  • 13 years ago
    I'm sorry, but it don't work.
  • 13 years ago
    You can solve it using properties in child form.

    Form 02

    private Object _YourObject;

    public object YourObject
        get {return _yourObject;}
        set {_YourObject = value;}

    Form 01

    Form2 form2 = new Form2();
    form2.YourObject = new form2.YourObject();

    After closing form2, you can use form2.YourObject.

    Ibrahim Faisal

  • 13 years ago
    OK, could you post the code that does not work for you here please?  Thanks!

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