var col = new DataGridViewColumn();
               //要插入列的类型
                col.CellTemplate = new DataGridViewTextBoxCell();
                col.Name = "colName";
                col.HeaderText = "显示名称";
                dgvWorkList.Columns.Insert(4, col);
                //插入列赋值
                for (int i = 0; i < dgvWorkList.Rows.Count; i++)
                {
                    dgvWorkList.Rows[i].Cells["colName"].Value = "value";
                }