如何读取多个CheckBox控件选中的Text文本

//方法1
private void button1_Click(object sender, EventArgs e)
        {
            //遍历groupBox里的所有控件:Comtrol
            foreach (Control c in groupBox3.Controls)     
            {//判断当前Comtrol是不是Checkbox控件?
               if (c is CheckBox)
               {//是,转换类型为Checkbox控件
                    CheckBox ck = c as CheckBox;
                //判断Checkbox控件是不是checked?
                   if (ck.Checked)
                   {//是,取Text文本
                    this.groupBox3.Text += ShowChecked(ck);
                   }
               }
            }
         }
 private string ShowChecked(CheckBox ck) //返回string类型
        {   //字符串构造器
            StringBuilder sb = new StringBuilder();
            if (ck.Checked)
            {   //自动带回车换行符
                sb.AppendLine(ck.Text);//没选中返回空
            }
            return sb.ToString(); //返回字符串
        }

//方法2
 private void button1_Click(object sender, EventArgs e)
        {
                        DealCheckboxes(groupBox3, groupBox3);
        }

        public void DealCheckboxes(Control container,Control contorlToDisplay)
        {
            contorlToDisplay.Text = "";
           foreach (Control c in container.Controls)
           {
             if (c is CheckBox)
             {
                 contorlToDisplay.Text += ShowChecked(c as CheckBox);
             }
           } 
        }
        private string ShowChecked(CheckBox ck) //返回string类型
        {   //字符串构造器
            StringBuilder sb = new StringBuilder();
            if (ck.Checked)
            {   //自动带回车换行符
                sb.AppendLine(ck.Text);//没选中返回空
            }
            return sb.ToString(); 
        }