Ячейки DataGridView как текстбоксы

        private void dataGridView1_CellMouseDown(object sender, DataGridViewCellMouseEventArgs e)
        {
           
            if ((e.RowIndex >= 0) & (e.ColumnIndex >= 0))
            {
                dataGridView1.CurrentCell = dataGridView1.Rows[e.RowIndex].Cells[e.ColumnIndex];
                dataGridView1.BeginEdit(true);
                dataGridView1.ClearSelection();
                
            }
 
        }

[DllImport("user32.dll")]
static extern bool SetCaretPos(int x, int y);
 
private void dataGridView1_CellMouseDown(object sender, DataGridViewCellMouseEventArgs e)
{
    if ((e.RowIndex >= 0) & (e.ColumnIndex >= 0))
    {
        dataGridView1.CurrentCell = dataGridView1.Rows[e.RowIndex].Cells[e.ColumnIndex];
        dataGridView1.BeginEdit(true);
        dataGridView1.ClearSelection();
        SetCaretPos(e.X, e.Y);
    }
}

DllImport("user32.dll")]
static extern bool SetCaretPos(int x, int y);

using System.Runtime.InteropServices;

private void Form1_Load(object sender, EventArgs e)
{
    dataGridView1.EditMode = DataGridViewEditMode.EditProgrammatically; //или dataGridView1.EditMode = DataGridViewEditMode.EditOnEnter;
    dataGridView1.CellMouseEnter += new DataGridViewCellEventHandler(dataGridView1_CellMouseEnter);
}
 
void dataGridView1_CellMouseEnter(object sender, DataGridViewCellEventArgs e)
{
    if (e.RowIndex >= 0 && e.ColumnIndex >= 0)
    {
        dataGridView1.CurrentCell = dataGridView1.Rows[e.RowIndex].Cells[e.ColumnIndex];
        dataGridView1.BeginEdit(false);
    }
}