下拉 回车 筛选

 List<string> GSCarNo = new List<string>();

//添加一空白选项
            GSCarNo.Add("");
tag=false

private void com_vehicle_code_KeyUp(object sender, KeyEventArgs e)
        {
            //回车模糊查询
            if (e.KeyCode == Keys.Enter)
            {
                if (com_vehicle_code.Text.Trim().Length != 0)
                {
                    if (radioCol.Checked)
                    {
                        List<string> subGSCarNo = GSCarNo.FindAll(GSMatchCarNo);
                        com_vehicle_code.DataSource = subGSCarNo;
                        if (com_vehicle_code.DroppedDown)
                        {
                            com_vehicle_code.DroppedDown = false;
                        }
                        else
                        {
                            com_vehicle_code.DroppedDown = true;
                        }
                    }
                    else if (radioHe.Checked)
                    {
                        List<string> subWGCarNo = WGCarNo.FindAll(GSMatchCarNo);
                        com_vehicle_code.DataSource = subWGCarNo;
                        if (com_vehicle_code.DroppedDown)
                        {
                            com_vehicle_code.DroppedDown = false;
                        }
                        else
                        {
                            com_vehicle_code.DroppedDown = true;
                        }
                    }
                }
            }
        }

private bool GSMatchCarNo(string s)
        {
            if (s.IndexOf(com_vehicle_code.Text.Trim()) > -1)
            {
                return true;
            }
            return false;
        }


if (com_vehicle_code.Text.Trim().Length == 0)
            {
                if (radioCol.Checked)
                {
                    com_vehicle_code.DataSource = GSCarNo;
                }
                else if (radioHe.Checked)
                {
                    com_vehicle_code.DataSource = WGCarNo;
                }
            }

   private void com_vehicle_code_DropDownClosed(object sender, EventArgs e)
        {
            com_vehicle_code.Tag = "false";
        }

if (radioHe.Checked)
            {
                DataRow[] drs = _dtcar.Select("vi_vehicle_code='" + com_vehicle_code.Text.Trim() + "'");
                if (drs.Length > 0)
                {
                    com_driver.Text = drs[0]["vi_driver_name"].ToString();
                    com_driver_phone.Text = drs[0]["vi_driver_mobile"].ToString();
                }
            }


 private void com_vehicle_code_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (radioHe.Checked)
            {
                DataRow[] drs = _dtcar.Select("vi_vehicle_code='" + com_vehicle_code.Text.Trim() + "'");
                if (drs.Length > 0)
                {
                    com_driver.Text = drs[0]["vi_driver_name"].ToString();
                    com_driver_phone.Text = drs[0]["vi_driver_mobile"].ToString();
                }
            }
        }