将多个选定的DataGridView行写入CSV

using System;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Windows.Forms;

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

        private void btnExport_Click(object sender, EventArgs e)
        {
            // 获取选定的行
            List<DataGridViewRow> selectedRows = new List<DataGridViewRow>();
            foreach (DataGridViewRow row in dataGridView.SelectedRows)
            {
                selectedRows.Add(row);
            }

            // 构建CSV文件内容
            StringBuilder csvContent = new StringBuilder();
            foreach (DataGridViewRow row in selectedRows)
            {
                for (int i = 0; i < row.Cells.Count; i++)
                {
                    csvContent.Append(row.Cells[i].Value.ToString());
                    if (i < row.Cells.Count - 1)
                    {
                        csvContent.Append(",");
                    }
                }
                csvContent.AppendLine();
            }

            // 写入CSV文件
            string csvFilePath = "output.csv";
            File.WriteAllText(csvFilePath, csvContent.ToString());

            MessageBox.Show("CSV文件已导出成功！");
        }
    }
}