如何使用listView c#对每行的2列求和

using System;
using System.Windows.Forms;

namespace ListViewSumExample
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            // 设置ListView的View属性为Details
            listView1.View = View.Details;

            // 添加两列到ListView控件中
            listView1.Columns.Add("列1");
            listView1.Columns.Add("列2");

            // 添加数据到ListView控件中
            ListViewItem item1 = new ListViewItem("1");
            item1.SubItems.Add("2");
            listView1.Items.Add(item1);

            ListViewItem item2 = new ListViewItem("3");
            item2.SubItems.Add("4");
            listView1.Items.Add(item2);

            // 对每行的两列求和
            int sum = 0;
            foreach (ListViewItem item in listView1.Items)
            {
                int column1Value = int.Parse(item.SubItems[0].Text);
                int column2Value = int.Parse(item.SubItems[1].Text);
                int rowSum = column1Value + column2Value;
                sum += rowSum;
            }

            // 显示求和结果
            MessageBox.Show("求和结果为：" + sum);
        }
    }
}