Showing/Hiding the main form in C#

Posted by DazSlayer on Stack Overflow See other posts from Stack Overflow or by DazSlayer
Published on 2011-01-15T20:50:49Z Indexed on 2011/01/15 20:53 UTC
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c#

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forms

I am working on a program where clicking on a button on form1 will open form2. I will then hide form1 until form2 is closed. The problem I have is that I cannot get form1 to show after form2 closes. Any ideas on how to fix this?

        try
        {
            Form1.ActiveForm.Hide();
            AddGradeForm = new Form2(Form.NumberOfSelections);
            AddGradeForm.ShowDialog();
            MessageBox.Show(AddGradeForm.Result.ToString());
        }
        catch (Exception i)
        {
            Form1.ActiveForm.Hide();
            AddGradeForm.Dispose();
            AddGradeForm = new Form2(Form.NumberOfSelections);
            AddGradeForm.ShowDialog();
            MessageBox.Show(AddGradeForm.Result.ToString());
        }
        Form1.ActiveForm.Show();

ERROR: NullReferenceException was unhanded. Object reference not set to an instance of an object.

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