Question

I have a datagridview that no matter what cell I click on returns an out of index error.

When I debug the following code I get a -1 value for e.ColumnIndex. As for e.RowIndex, I get the correct row that I have clicked on.

 private void dataGridView1_CellClick(object sender, DataGridViewCellEventArgs e)
    {
        form2.value = dataGridView1.Rows[e.RowIndex].Cells[e.ColumnIndex].Value.ToString();
    }

I have tried to replace the e.ColumnIndex with a static int just to see if it works. When I add the int it doesn’t do anything when I click on a particular row or column.

Anyone any ideas how I can change the ColumnIndex or how I can work around this issue.

Answer 1

-1 for e.ColumnIndex indicates that the RowHeader is being selected. Are you sure you don’t have the RowSelected event bound to this event as well?

In any case, it is good practice to have checks of e.ColumnIndex and e.RowIndex that both are 0 or greater in any CellClick event- the RowHeader and ColumnHeader cells will also fire this event when clicked, and would not contain data, which would be somewhat confusing for users.