//向DGV添加行
 private void pos_main_Load(object sender, EventArgs e)
        {
            DataGridViewCheckBoxColumn newcolumns = new DataGridViewCheckBoxColumn();
            newcolumns.HeaderText = "选择";
            this.data_list.Columns.Add("1", "货号");
            this.data_list.Columns.Add("2", "品名");
            this.data_list.Columns.Add("3", "产地");
            this.data_list.Columns.Add("4", "规格");
            this.data_list.Columns.Add("5", "单位");
            this.data_list.Columns.Add("6", "零售价");
            this.data_list.Columns.Add("7", "数量");
            this.data_list.Columns.Add(newcolumns);
            this.data_list.Columns[0].Width = 90;
            this.data_list.Columns[1].Width = 180;
            this.data_list.Columns[2].Width = 90;
            this.data_list.Columns[3].Width = 90;
            this.data_list.Columns[4].Width = 58;
            this.data_list.Columns[5].Width = 90;
            this.data_list.Columns[6].Width = 62;
            this.data_list.Columns[7].Width = 50; ;
        }

For index = 0 To detailList.Count - 1
                Dim cellCheckBox1 As DataGridViewCheckBoxCell = New DataGridViewCheckBoxCell
                cellCheckBox1.Style.Alignment = DataGridViewContentAlignment.MiddleCenter
                DgvSekisanItiran.Rows(index).Cells(7) = cellCheckBox1
            Next

------解决方案--------------------

判断那一列每个单元格的值,因为checkbox返回值是1或0或null
ok,如果是1,就删除为1的行就好了.
用vb.net写法
VB.NET code
for i as integer dgv.rows.count-2 to 0 step -1    'gv.rows.count-2是除去那个动态添加行
if dgv.rows(i).cells(7).formattedvalue=1 then    '用formattedvalue属性直接可以可以去除null的判断
dgv.rows.removeat(i)
end if
next