What better way to align columns of DataGridView C #

Use this extension in your code, it sets the datagridview , and leaves the columns "free" if the user wants to resize, and already formats the columns that are decimal.

public static class Extensions
{
    public static void AjeitaDataGridView(this DataGridView dataGridView)
    {
        //para deixar o tamanho "certo e editavel" o tamanho da coluna
        // all cells bloqueia o usuario a nao editar
        dataGridView.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.AllCells;

        for (int i = 0; i < dataGridView.Columns.Count; i++)
        {
            int colw = dataGridView.Columns[i].Width;
            if (dataGridView.Columns[i].ValueType == typeof(Decimal))
            {
                dataGridView.Columns[i].DefaultCellStyle.Format = "N2";
            }
            //
            dataGridView.Columns[i].Width = colw;
        }

        dataGridView.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.None;
    }
}

and in your code just call ..

this.datagridview1.AjeitaDataGridView();

Reference: How do you automatically resize columns in a DataGridView control AND allow the user to resize the columns on that same grid?

I use:

dgv.AutoSizeColumnsMode = DataGridViewAutoSizeColumnsMode.AllCells;

The column widths are adjusted so that the contents of all the cells in the columns, including the header cells, fit into it.

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