c#实现从txt文本里读取大量数据到Datetable再绑定到datagirdview，再导出到excel

客户有一个需求是把扫描和称重的数据写入到txt文本里面

然后导出显示到界面，最后导出到Excel。

就是这个流程。

从txt导出到datetable中。。。还是直接上代码吧

/// <summary>
   /// txt导出到datatable
   /// </summary>
   /// <param name="dt">datatable</param>
   /// <param name="path">txt文件路径</param>
   /// <param name="a">列表序号</param>
   /// <returns></returns>

private System.Data.DataTable datateble(System.Data.DataTable dt,string path,int a)
        {
            try
            {
                StreamReader st = new StreamReader(path);
                dt.Columns.Add("序号", typeof(string));
                dt.Columns.Add("数据内容", typeof(string));
                dt.Columns.Add("时间", typeof(string));
                String line;
                while ((line = st.ReadLine()) != null)
                {
                    a++;
                    DataRow dr = dt.NewRow();
                    string[] strs = line.Split(‘|‘);
                    dr[0] = a.ToString();
                    dr[2] = strs[0];
                    dr[1] = strs[1];

                    dt.Rows.Add(dr);
                }
                st.Close();
                return dt;
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }

　 返回datatable类型，然后 绑定到datagirdview显示

导出到excel文件

using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
//using Microsoft.Office.Interop.Excel;
using System.Windows.Forms;
using System.Threading;
using System.IO;
using Commonication_Program.CONFIG;
using System.Data;
using System.Threading.Tasks;

namespace Commonication_Program.RINTRUN
{
    class Rt_Excel
    {

        public Microsoft.Office.Interop.Excel.Application m_xlApp = null;
        /// <summary>
        /// 将DataTable数据导出到Excel表
        /// </summary>
        /// <param name="tmpDataTable">要导出的DataTable</param>
        /// <param name="strFileName">Excel的保存路径及名称</param>
        /// <param name="path">txt存放路径</param>
        public void DataTabletoExcel(System.Data.DataTable tmpDataTable, string strFileName,string path)
        {
            if (tmpDataTable == null)
            {
                return;
            }

            long rowNum = tmpDataTable.Rows.Count;//行数
            int columnNum = tmpDataTable.Columns.Count;//列数
            m_xlApp = new Microsoft.Office.Interop.Excel.Application();

            m_xlApp.DisplayAlerts = false;//不显示更改提示
            m_xlApp.Visible = false;

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

                if (rowNum > 65536)//单张Excel表格最大行数
                {
                    long pageRows = 65535;//定义每页显示的行数,行数必须小于65536
                    int scount = (int)(rowNum / pageRows);//导出数据生成的表单数
                    if (scount * pageRows < rowNum)//当总行数不被pageRows整除时，经过四舍五入可能页数不准
                    {
                        scount = scount + 1;
                    }
                    for (int sc = 1; sc <= scount; sc++)
                    {
                        if (sc > 1)
                        {
                            object missing = System.Reflection.Missing.Value;
                            worksheet = (Microsoft.Office.Interop.Excel.Worksheet)workbook.Worksheets.Add(
                                        missing, missing, missing, missing);//添加一个sheet
                        }
                        else
                        {
                            worksheet = (Microsoft.Office.Interop.Excel.Worksheet)workbook.Worksheets[sc];//取得sheet1
                        }
                        string[,] datas = new string[pageRows + 1, columnNum];

                        for (int i = 0; i < columnNum; i++) //写入字段
                        {
                            datas[0, i] = tmpDataTable.Columns[i].Caption;//表头信息
                        }

                        int init = int.Parse(((sc - 1) * pageRows).ToString());
                        int r = 0;
                        int index = 0;
                        int result;
                        if (pageRows * sc >= rowNum)
                        {
                            result = (int)rowNum;
                        }
                        else
                        {
                            result = int.Parse((pageRows * sc).ToString());
                        }

                        for (r = init; r < result; r++)
                        {
                            index = index + 1;
                            for (int i = 0; i < columnNum; i++)
                            {
                                object obj = tmpDataTable.Rows[r][tmpDataTable.Columns[i].ToString()];
                                datas[index, i] = obj == null ? "" : "‘" + obj.ToString().Trim();//在obj.ToString()前加单引号是为了防止自动转化格式
                            }
                            System.Windows.Forms.Application.DoEvents();
                            //添加进度条
                        }

                        Microsoft.Office.Interop.Excel.Range fchR = worksheet.Range[worksheet.Cells[1, 1], worksheet.Cells[index + 1, columnNum]];
                        fchR.Value2 = datas;
                        worksheet.Columns.EntireColumn.AutoFit();//列宽自适应。
                        m_xlApp.WindowState = Microsoft.Office.Interop.Excel.XlWindowState.xlMaximized;//Sheet表最大化

                    }
                }
                else
                {
                    string[,] datas = new string[rowNum + 1, columnNum];
                    for (int i = 0; i < columnNum; i++) //写入字段
                    {
                        datas[0, i] = tmpDataTable.Columns[i].Caption;
                    }
                    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()前加单引号是为了防止自动转化格式
                        }
                        System.Windows.Forms.Application.DoEvents();
                        //添加进度条
                    }
                    Microsoft.Office.Interop.Excel.Range fchR = worksheet.Range[worksheet.Cells[1, 1], worksheet.Cells[rowNum + 1, columnNum]];
                    fchR.Value2 = datas;

                    worksheet.Columns.EntireColumn.AutoFit();//列宽自适应。
                    m_xlApp.WindowState = Microsoft.Office.Interop.Excel.XlWindowState.xlMaximized;

                }
                workbook.Saved = true;
                workbook.SaveCopyAs(strFileName);
                workbook.Close();
                MessageBox.Show("文件已导出！","提示",MessageBoxButtons.OK,MessageBoxIcon.Information);
                FileStream stream = File.Open(path, FileMode.OpenOrCreate, FileAccess.Write);
                stream.Seek(0, SeekOrigin.Begin);
                stream.SetLength(0);
                stream.Close();
            }
            catch (Exception ex）
            {
                MessageBox.Show("导出异常：" + ex.Message, "导出异常", MessageBoxButtons.OK, MessageBoxIcon.Warning);
            }
            finally
            {
                m_xlApp.Workbooks.Close();
                m_xlApp.Workbooks.Application.Quit();
                m_xlApp.Application.Quit();
                m_xlApp.Quit();
                m_xlApp = null;
            }
        }
}
}

　 导出十几万的数据到excel表，需要几秒钟，导出后清空txt文本。

数据越大导出越慢，当然一天的数据产量也最多在十万左右

这种方式客户欣然接受了

当然还有更快导出更大量数据到excel的方式，懒得去弄了

原文地址：https://www.cnblogs.com/wl192/p/12207097.html