private void GenerateForeignButton_Click(object sender, EventArgs e) { string table1 = TablesList1.GetItemText(TablesList1.SelectedItem); string table2 = TablesList2.GetItemText(TablesList2.SelectedItem); string column1 = ColumnListBox.GetItemText(ColumnListBox.SelectedItem); string column2 = ColumnListBox2.GetItemText(ColumnListBox2.SelectedItem); saveFileDialog1.Filter = "Text file (*.txt)|*.txt|All files (*.*)|*.*|Structured Query Language file (*.sql)|*.sql"; saveFileDialog1.FilterIndex = 2; saveFileDialog1.RestoreDirectory = true; if (saveFileDialog1.ShowDialog() == DialogResult.OK) { System.IO.File.AppendAllText(saveFileDialog1.FileName, Environment.NewLine + Environment.NewLine + "if not exists(select 1 from sysobjects where name='" + table2 + ")' \n alter table " + table1 + " add constraint " + table2 + " foreign key (" + column1 + ") references " + column2); } }