Remove duplicate code

Question

Hi ,

i have the following code in the textbox(used from another user) .

  private void textBox4_KeyDown(object sender, KeyEventArgs e)
        {
           
            if (dataGridView1.CurrentCell == null)
            {
                return;
            }
            else
            {
                rpos = dataGridView1.CurrentCell.RowIndex;
                cpos = dataGridView1.CurrentCell.ColumnIndex;

                switch (e.KeyCode)
                {
                    case Keys.Up:

                        rpos--;
                        if (rpos >= 0) dataGridView1.CurrentCell = dataGridView1.Rows[rpos].Cells[cpos];
                        e.Handled = true;
                        break;
                    case Keys.Down:

                        rpos++;
                        if (rpos < dataGridView1.Rows.Count) dataGridView1.CurrentCell = dataGridView1.Rows[rpos].Cells[cpos];
                        e.Handled = true;
                        break;

now i also i have a customdatagridview on which i have the below code

   protected override void OnEditingControlShowing(DataGridViewEditingControlShowingEventArgs e)
        {
            

            e.Control.KeyPress -= new KeyPressEventHandler(textbox_keypress);
            e.Control.TextChanged -= new EventHandler(TextBox_TextChanged);
            e.Control.KeyDown -= new KeyEventHandler(TextBox_KeyDown);
            e.Control.Enter -= new EventHandler(TextBox_Enter);
            if (this.CurrentCell.ColumnIndex == 1 || this.CurrentCell.ColumnIndex == 2) // 
            {
                TextBox textBox = e.Control as TextBox;
                if (textBox != null)
                {
                    textBox.KeyPress += new KeyPressEventHandler(textbox_keypress);
                }
            }

            else if (this.CurrentCell.ColumnIndex == 0) 
            {
                TextBox textBox = e.Control as TextBox;
                if (textBox != null)
                {
                    textBox.TextChanged += TextBox_TextChanged; // Attach TextChanged event handler
                    textBox.KeyDown += TextBox_KeyDown; // Attach KeyDown event handler
                    textBox.Enter += TextBox_Enter;
                }
            }
            base.OnEditingControlShowing(e);
        }

  private void TextBox_KeyDown(object sender, KeyEventArgs e)
        {
            if (this.CurrentCell.ColumnIndex == 0) // Assuming the first column has an index of 0
            {
                TextBox textBox = (TextBox)sender;

                //code for results up and down in popup datagridview

                if (dgv.CurrentCell == null)
                {
                    return;
                }
                else
                {
                    
                    rpos = dgv.CurrentCell.RowIndex;
                    cpos = dgv.CurrentCell.ColumnIndex;
                    switch (e.KeyCode)
                    {
                        case Keys.Up:

                            rpos--;
                            if (rpos >= 0) dgv.CurrentCell = dgv.Rows[rpos].Cells[cpos];
                            e.Handled = true;
                            break;
                        case Keys.Down:

                            rpos++;
                            if (rpos < dgv.Rows.Count) dgv.CurrentCell = dgv.Rows[rpos].Cells[cpos];
                            e.Handled = true;


                            break;

I want to create a common method which works for both controls as the maximum code is similar so that the duplicacy of the code can be removed .

Answer 1

Hi @ankit goel , Welcome to Microsoft Q&A,

Yes, just extract the same code.

For example:

private void customevent(DataGridView dgv, KeyEventArgs e)
{
    //code for results up and down in popup datagridview
    if (dgv.CurrentCell == null)
    {
        return;
    }
    else
    {

        int rpos = dgv.CurrentCell.RowIndex;
        int cpos = dgv.CurrentCell.ColumnIndex;
        switch (e.KeyCode)
        {
            case Keys.Up:

                rpos--;
                if (rpos >= 0) dgv.CurrentCell = dgv.Rows[rpos].Cells[cpos];
                e.Handled = true;
                break;
            case Keys.Down:

                rpos++;
                if (rpos < dgv.Rows.Count) dgv.CurrentCell = dgv.Rows[rpos].Cells[cpos];
                e.Handled = true;
                break;
        }

    }
}

Then you can use it in a similar way.

private void textBox2_KeyDown(object sender, KeyEventArgs e)
{
    if (dgv.CurrentCell.ColumnIndex == 0) // Assuming the first column has an index of 0
    {
        TextBox textBox = (TextBox)sender;
        customevent(dgv, e);
    }
}
private void textBox1_KeyDown(object sender, KeyEventArgs e)
{
    customevent(dataGridView1, e);
}

Best Regards,

Jiale

---

If the answer is the right solution, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment". 

Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.