C# 开发SQL sever数据库数据导出为Excel

你可以使用C#中的Microsoft.Office.Interop.Excel 库将SQL Server数据库数据导出为Excel文件。以下是一个简单的示例代码：

using System;
using System.Data;
using System.Data.SqlClient;
using System.IO;
using Excel = Microsoft.Office.Interop.Excel;

namespace ExportToExcel
{
    class Program
    {
        static void Main(string[] args)
        {
            string connectionString = "Data Source=myServerAddress;Initial Catalog=myDataBase;User ID=myUsername;Password=myPassword";
            string query = "SELECT * FROM myTable";

            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                using (SqlCommand command = new SqlCommand(query, connection))
                {
                    connection.Open();
                    SqlDataReader reader = command.ExecuteReader();

                    DataTable dataTable = new DataTable();
                    dataTable.Load(reader);

                    Excel.Application excel = new Excel.Application();
                    excel.Visible = false;
                    excel.DisplayAlerts = false;

                    Excel.Workbook workbook = excel.Workbooks.Add(Type.Missing);
                    Excel.Worksheet worksheet = workbook.ActiveSheet;

                    for (int i = 0; i < dataTable.Columns.Count; i++)
                    {
                        worksheet.Cells[1, i + 1] = dataTable.Columns[i].ColumnName;
                    }

                    for (int i = 0; i < dataTable.Rows.Count; i++)
                    {
                        for (int j = 0; j < dataTable.Columns.Count; j++)
                        {
                            worksheet.Cells[i + 2, j + 1] = dataTable.Rows[i][j];
                        }
                    }

                    workbook.SaveAs("output.xlsx");
                    workbook.Close();
                    excel.Quit();
                }
            }
        }
    }
}

其中，`connectionString`是数据库连接字符串，`query`是要执行的SQL查询语句，`output.xlsx`是导出的Excel文件名。

请注意，为了使用`Microsoft.Office.Interop.Excel`库，你需要在Visual Studio中添加`Microsoft Excel 16.0 Object Library`引用。你可以在Visual Studio中的“项目”->“添加引用”菜单中找到它。