C#將dataGridView中顯示的數據導出到Excel（大數據量超有用版）

       開發中非常多情況下須要將dataGridView控件中顯示的數據結果以Excel或者Word的形式導出來，本例就來實現這個功能。

因為從數據庫中查找出某些數據列可能不是必需顯示出來，在dataGridView中將相應的列隱藏了。這時導出時就會將隱藏的列導出來。顯然不是我們所預期的。

做法是先將dataGridView中顯示的部分存進DataTable。然后就DataTable導出到Excel，代碼例如以下：

第一步：加入Excel引用

第二步：創建類

using System;
using System.Collections;
using System.Text;
using System.Data;
using System.Threading;
using System.Windows.Forms;
using System.Collections.Generic;
using Microsoft.Office.Core;
using Excel = Microsoft.Office.Interop.Excel;

public class ExportToExcel
{
    public Excel.Application m_xlApp = null;

    public void OutputAsExcelFile(DataGridView dataGridView)
    {
        if (dataGridView.Rows.Count <= 0)
        {
            MessageBox.Show("無數據！
","提示",MessageBoxButtons.OK,MessageBoxIcon.Warning); return;
        }
        string filePath="";
        SaveFileDialog s = new SaveFileDialog();
        s.Title = "保存Excel文件";
        s.Filter = "Excel文件(*.xls)|*.xls";
        s.FilterIndex = 1;
        if (s.ShowDialog() == DialogResult.OK)
            filePath = s.FileName;
        else
            return;

        //第一步：將dataGridView轉化為dataTable,這樣能夠過濾掉dataGridView中的隱藏列

        DataTable tmpDataTable = new DataTable("tmpDataTable");
        DataTable modelTable = new DataTable("ModelTable");
        for (int column = 0; column < dataGridView.Columns.Count; column++)
        {
            if (dataGridView.Columns[column].Visible == true)
            {
                DataColumn tempColumn = new DataColumn(dataGridView.Columns[column].HeaderText, typeof(string));
                tmpDataTable.Columns.Add(tempColumn);
                DataColumn modelColumn = new DataColumn(dataGridView.Columns[column].Name, typeof(string));
                modelTable.Columns.Add(modelColumn);
            }
        }
        for (int row = 0; row < dataGridView.Rows.Count; row++)
        {
            if (dataGridView.Rows[row].Visible == false)
                continue;
            DataRow tempRow = tmpDataTable.NewRow();
            for (int i = 0; i < tmpDataTable.Columns.Count; i++)
                tempRow[i] = dataGridView.Rows[row].Cells[modelTable.Columns[i].ColumnName].Value;
            tmpDataTable.Rows.Add(tempRow);
        }
        if (tmpDataTable == null)
        {
            return;
        }

        //第二步：導出dataTable到Excel
        long rowNum = tmpDataTable.Rows.Count;//行數
        int columnNum = tmpDataTable.Columns.Count;//列數
        Excel.Application m_xlApp = new Excel.Application();
        m_xlApp.DisplayAlerts = false;//不顯示更改提示
        m_xlApp.Visible = false;

        Excel.Workbooks workbooks = m_xlApp.Workbooks;
        Excel.Workbook workbook = workbooks.Add(Excel.XlWBATemplate.xlWBATWorksheet);
        Excel.Worksheet worksheet = (Excel.Worksheet)workbook.Worksheets[1];//取得sheet1

        try
        {
            string[,] datas = new string[rowNum + 1, columnNum];
            for (int i = 0; i < columnNum; i++) //寫入字段
                datas[0, i] = tmpDataTable.Columns[i].Caption;
            //Excel.Range range = worksheet.get_Range(worksheet.Cells[1, 1], worksheet.Cells[1, columnNum]);
            Excel.Range range = m_xlApp.Range[worksheet.Cells[1, 1], worksheet.Cells[1, columnNum]];
            range.Interior.ColorIndex = 15;//15代表灰色
            range.Font.Bold = true;
            range.Font.Size = 10;

            int r = 0;
            for (r = 0; r < rowNum; r++)
            {
                for (int i = 0; i < columnNum; i++)
                {
                    object obj = tmpDataTable.Rows[r][tmpDataTable.Columns[i].ToString()];
                    datas[r + 1, i] = obj == null ? "" : "'" + obj.ToString().Trim();//在obj.ToString()前加單引號是為了防止自己主動轉化格式
                }
                System.Windows.Forms.Application.DoEvents();
                //加入進度條
            }
            //Excel.Range fchR = worksheet.get_Range(worksheet.Cells[1, 1], worksheet.Cells[rowNum + 1, columnNum]);
            Excel.Range fchR = m_xlApp.Range[worksheet.Cells[1, 1], worksheet.Cells[rowNum + 1, columnNum]];
            fchR.Value2 = datas;

            worksheet.Columns.EntireColumn.AutoFit();//列寬自適應。

            //worksheet.Name = "dd";

            //m_xlApp.WindowState = Excel.XlWindowState.xlMaximized;
            m_xlApp.Visible = false;

            // = worksheet.get_Range(worksheet.Cells[1, 1], worksheet.Cells[rowNum + 1, columnNum]);
            range = m_xlApp.Range[worksheet.Cells[1, 1], worksheet.Cells[rowNum + 1, columnNum]];

            //range.Interior.ColorIndex = 15;//15代表灰色
            range.Font.Size = 9;
            range.RowHeight = 14.25;
            range.Borders.LineStyle = 1;
            range.HorizontalAlignment = 1;
            workbook.Saved = true;
            workbook.SaveCopyAs(filePath);
        }
        catch (Exception ex)
        {
            MessageBox.Show("導出異常：" + ex.Message, "導出異常", MessageBoxButtons.OK, MessageBoxIcon.Warning);
        }
        finally
        {
            EndReport();
        }

        m_xlApp.Workbooks.Close();
        m_xlApp.Workbooks.Application.Quit();
        m_xlApp.Application.Quit();
        m_xlApp.Quit();
        MessageBox.Show("導出成功！", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
    }
    private void EndReport()
    {
        object missing = System.Reflection.Missing.Value;
        try
        {
            //m_xlApp.Workbooks.Close();
            //m_xlApp.Workbooks.Application.Quit();
            //m_xlApp.Application.Quit();
            //m_xlApp.Quit();
        }
        catch { }
        finally
        {
            try
            {
                System.Runtime.InteropServices.Marshal.ReleaseComObject(m_xlApp.Workbooks);
                System.Runtime.InteropServices.Marshal.ReleaseComObject(m_xlApp.Application);
                System.Runtime.InteropServices.Marshal.ReleaseComObject(m_xlApp);
                m_xlApp = null;
            }
            catch { }
            try
            {
                //清理垃圾進程
                this.killProcessThread();
            }
            catch { }
            GC.Collect();
        }
    }

    private void killProcessThread()
    {
        ArrayList myProcess = new ArrayList();
        for (int i = 0; i < myProcess.Count; i++)
        {
            try
            {
                System.Diagnostics.Process.GetProcessById(int.Parse((string)myProcess[i])).Kill();
            }
            catch { }
        }
    }
}

第三步：調用

ExportToExcel d = new ExportToExcel();
d.OutputAsExcelFile(dataGridView1);