DataGridView autoresize columns does not seem to do anything?

I have looked at several posts and answers related to autoresize but I don't see an the answer (or more likely, I don't understand how to apply).  The call to autoresize does not seem to do anything to my dgv.  I have tried several variations per the posts.  I have attached my code.  It is probably something dumb.  Any suggestions would be appreciated.  

        public frmSearchResults(string sql, Connection oConn)
        {
            InitializeComponent();
            //Pull the specialty information in.
            dgvSearchResults.DataSource = null;
            dgvSearchResults.Columns.Clear();
            DataSet dsData = oConn.ExecuteDataSet(sql, false);
            BindingSource bsData = new BindingSource();
            bsData.DataSource = dsData.Tables[0];
            dgvSearchResults.DataSource = dsData.Tables[0];
            dgvSearchResults.Columns["ENTITY_TYPE_CODE"].HeaderText = "Type Code";

            //dgvSearchResults.AutoResizeColumns(DataGridViewAutoSizeColumnsMode.DisplayedCells);
            dgvSearchResults.AutoResizeColumns(DataGridViewAutoSizeColumnsMode.AllCells);
            this.Refresh();
        }