try

            {

                OpenFileDialog openFileDialog = new OpenFileDialog();

                string str = comboBox_hexFilePath.Text;

                string file = str.Substring(, str.LastIndexOf("\\") + );//去掉了路径

                openFileDialog.InitialDirectory = file;

                openFileDialog.Filter = "Hex文件|*.hex";

                openFileDialog.RestoreDirectory = true;

                openFileDialog.FilterIndex = ;

                    comboBox_hexFilePath.Text = openFileDialog.FileName;//文件名

                }

            }

            catch

            {

                show_info("hex文件选择..");

            }