C# DataGridView 全选 反选

internal void AddFullSelect()
{
if (this.dtGrdVwMdt.Rows.Count < 1)
{
return;
}
System.Windows.Forms.CheckBox ckBox = new System.Windows.Forms.CheckBox();
ckBox.Text = "全选";
ckBox.Checked = false;
System.Drawing.Rectangle rect =
this.dtGrdVwMdt.GetCellDisplayRectangle(0, -1, true);
ckBox.Size = new System.Drawing.Size(this.dtGrdVwMdt.Columns[0].Width, 25);
ckBox.Location = rect.Location;
ckBox.CheckedChanged += new EventHandler(ckBox_CheckedChanged);
this.dtGrdVwMdt.Controls.Add(ckBox);
}
internal void ckBox_CheckedChanged(object sender, EventArgs e)
{
for (int i = 0; i < this.dtGrdVwMdt.Rows.Count; i++)
{
this.dtGrdVwMdt.Rows[i].Cells[0].Value = ((System.Windows.Forms.CheckBox)sender).Checked;
}
this.dtGrdVwMdt.EndEdit();
}

///判断CheckBox是否被选中

for (int i = 0; i < dataGridView1.Rows.Count; i++)
{
    if ((bool)dataGridView1.Rows[i].Cells[0].EditedFormattedValue==true)
      {
        //TODO
      }
}  第二种  参考
            //添加选择框            DataGridViewCheckBoxColumn columnb = new DataGridViewCheckBoxColumn();            if (flagquanju)            {                System.Windows.Forms.CheckBox ckBox = new System.Windows.Forms.CheckBox();                ckBox.Size = new Size(15, 15);                //ckBox.Text = "全选";                ckBox.Checked = false;                ckBox.BackColor = Color.FromArgb(0, 40, 60, 82); //设置背景透明
                System.Drawing.Rectangle rect =                dtGrdVwMdt.GetCellDisplayRectangle(0, -1, true);   //获取位置                  Rectangle oRectangle = dtGrdVwMdt.GetCellDisplayRectangle(0, 0, true);                Point oPoint = new Point();                oPoint.X = 65 + (oRectangle.Width - ckBox.Width) / 2 + 1;                oPoint.Y = 20 + (oRectangle.Height - ckBox.Height) / 2 + 1;                ckBox.Location = rect.Location;//设置位置                ckBox.Location = oPoint;                ckBox.CheckedChanged += new EventHandler(SetAllRowChecked);                                dtGrdVwMdt.Controls.Add(ckBox);
 
                columnb.Width = 50;                // columnb.Name = "cb_check";                columnb.TrueValue = "IsScienceNature";                columnb.FalseValue = "IsChecked";                dtGrdVwMdt.Columns.Insert(0, columnb);                flagquanju = false;            }