Datagridview forcing only one checkbox to be selected in a column

Question

How do I force only a single checkbox to be checked in a column of a Datagridview?

Answer 1

You can use CellEndEdit event of DGV, as it occurs after when the cell is modified. Kindly read the comments in below code snippet to use the code below:

private void dgrvUserProfileView_CellEndEdit(object sender, DataGridViewCellEventArgs e)
{
    int CheckedCount = 0;

    //Make sure you have set True Value/ false Value property of check box column to 1/0 or true/false resp.
    //Lets say your column 5th(namely Department) is a checked box column
    if (dgrvUserProfileView.Columns[e.ColumnIndex].Name == "Department")
    {
        for (int i = 0; i <= dgrvUserProfileView.Rows.Count - 1; i++)
        {
            if (Convert.ToBoolean(dgrvUserProfileView.Rows[i].Cells["Department"].Value) == true)
            {
                CheckedCount = CheckedCount + 1;
            }
        }

        if (CheckedCount == 1)
        {
            for (int i = 0; i <= dgrvUserProfileView.Rows.Count - 1; i++)
            {
                if (Convert.ToBoolean(dgrvUserProfileView.Rows[i].Cells["Department"].Value) == true)
                {
                    dgrvUserProfileView.Rows[i].Cells["Department"].ReadOnly = true;
                }
            }
        }
        else
        {
            for (int i = 0; i <= dgrvUserProfileView.Rows.Count - 1; i++)
            {
                dgrvUserProfileView.Rows[i].Cells["Department"].ReadOnly = false;
            }
        }
    }
}

Hope this helps!