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Application.Run(new GUI());					

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    public partial class Form2 : Form
    {
        public delegate void FileSelectedDelegate(string Filename);

        public event FileSelectedDelegate FileSelected;

        private void button1_Click(object sender, EventArgs e)
        {
            FileSelected("Foo");
        }
    }					

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        private void button3_Click(object sender, EventArgs e)
        {
            Form2 f = new Form2();
            f.FileSelected += new Form2.FileSelectedDelegate(f_FileSelected);
            f.ShowDialog();
        }

        void f_FileSelected(string Filename)
        {
            MessageBox.Show(Filename);
        }					

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            Form2 f = new Form2();
            f.FileSelected += new Form2.FileSelectedDelegate(f_FileSelected);					

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Form2 f = new Form2();