How to change the width of the index column/ left most coumn in datagridview

Question

I want to change the width of the column indicated in the picture.(with question mark "?") What is the index or location of that column.

also, what is the name of that column?

I was able to change the width of other column by the below code.

dataGridView_A0.Columns[0].Width = 90;

Answer 1

You are looking for the grids RowHeadersWidth property... That particular column is referred to as the grids Row Headers Column.

dataGridView1.RowHeadersWidth = 90;