C# DataGridView

   private void InitDataGridView()
        {

            // Create an unbound DataGridView by declaring a column count.
            dataGridView1.ColumnCount = 3;
            dataGridView1.ColumnHeadersVisible = true;
            dataGridView1.AllowUserToAddRows = false;
            dataGridView1.AllowUserToDeleteRows = false;
            dataGridView1.AllowUserToOrderColumns = false;      
            dataGridView1.MultiSelect = false;
            dataGridView1.SelectionMode = DataGridViewSelectionMode.FullRowSelect;
            dataGridView1.ReadOnly = true;


            // Set the column header style.
            DataGridViewCellStyle columnHeaderStyle = new DataGridViewCellStyle();

            columnHeaderStyle.BackColor = Color.Beige;
            columnHeaderStyle.Font = new Font("Verdana", 10, FontStyle.Regular);
            dataGridView1.ColumnHeadersDefaultCellStyle = columnHeaderStyle;

            // Set the column header names.
            dataGridView1.Columns[0].Name = "C1";
            dataGridView1.Columns[1].Name = "C2";
            dataGridView1.Columns[2].Name = "C3";      
            


        }
        private void AddDataGridViewData()
        {
            for (int i = 0; i < 3; i++)
            {
                int index = this.dataGridView1.Rows.Add();
                this.dataGridView1.Rows[index].Cells[0].Value = i.ToString() + "1";
                this.dataGridView1.Rows[index].Cells[1].Value = i.ToString() + "2";
                this.dataGridView1.Rows[index].Cells[2].Value = i.ToString() + "3";
            }           

        }

        private string GetSelectedValue()
        {
            int index= dataGridView1.CurrentRow.Index;
            return dataGridView1.Rows[index].Cells["C2"].Value.ToString();           
            
        }

        //右键显示菜单
        private void dataGridView1_CellMouseDown(object sender, DataGridViewCellMouseEventArgs e)
        {
            if (e.Button == MouseButtons.Right)
            {
                if (e.RowIndex >= 0)
                {
                    //若行已是选中状态就不再进行设置
                    if (dataGridView1.Rows[e.RowIndex].Selected == false)
                    {
                        dataGridView1.ClearSelection();
                        dataGridView1.Rows[e.RowIndex].Selected = true;
                    }
                    //只选中一行时设置活动单元格
                    if (dataGridView1.SelectedRows.Count == 1)
                    {
                        dataGridView1.CurrentCell = dataGridView1.Rows[e.RowIndex].Cells[e.ColumnIndex];
                    }
                    //弹出操作菜单
                    contextMenuStrip1.Show(MousePosition.X, MousePosition.Y);
                }
            }
        }

 //清除DataGridView数据
        private void DataGridViewClear()
        {
            
            for (int i = 0; i < dataGridView1.RowCount; i++)
            {
                dataGridView1.Rows.Remove(dataGridView1.Rows[i]);
                i--;
            }
        }