C#高效导出Excel(IList转DataTable,DataSet)

微软的Excel操作类导出Excel会很慢，此方法简单的把表中内容以字符串的形式写入到Excel中，用到的一个技巧就是"\t".

C#中的\t相当于Tab键，写入到Excel中时就是一列一列中写入。

引用命名空间：

using System.Drawing;

using System.Threading;

using System.IO;

using System.Data;

using System.Text;

using System.Collections;

 

protected void btnExport_Click(object sender, EventArgs e)

    {

        this.labPercent.Text = "";

        IList<ViewUserInfo> userList = viewUserInfoService.GetUserInfoListAll();

        DataTable dt = IListOut(userList);

        WriteExcel(dt, "d:\\a.xls");

    }

    #region 导出Excel

    public void WriteExcel(DataTable ds, string path)

    {

        long totalCount = ds.Rows.Count;

        Thread.Sleep(1000);

        long rowRead = 0;

        float percent = 0;



        StreamWriter sw = new StreamWriter(path, false, Encoding.GetEncoding("gb2312"));

        StringBuilder sb = new StringBuilder();

        for (int k = 0; k < ds.Columns.Count; k++)

        {

            sb.Append(ds.Columns[k].ColumnName.ToString() + "\t");

        }

        sb.Append(Environment.NewLine);

        for (int i = 0; i < ds.Rows.Count; i++)

        {

            //rowRead++;

            //percent = ((float)(100 * rowRead)) / totalCount;

            this.labPercent.Text ="<a href='UserInfo.xls' target='_blank'>此处下载</a>";

            for (int j = 0; j < ds.Columns.Count; j++)

            {

                sb.Append(ds.Rows[i][j].ToString() + "\t");

            }

            sb.Append(Environment.NewLine);

        }

        sw.Write(sb.ToString());

        sw.Flush();

        sw.Close();

    }

    public DataTable IListOut(IList<ViewUserInfo> ResList)

    {

        DataTable TempDT = new DataTable();



        //此处遍历IList的结构并建立同样的DataTable

        System.Reflection.PropertyInfo[] p = ResList[0].GetType().GetProperties();

        foreach (System.Reflection.PropertyInfo pi in p)

        {

            TempDT.Columns.Add(pi.Name, System.Type.GetType(pi.PropertyType.ToString()));

        }



        for (int i = 0; i < ResList.Count; i++)

        {

            ArrayList TempList = new ArrayList();

            //将IList中的一条记录写入ArrayList

            foreach (System.Reflection.PropertyInfo pi in p)

            {

                object oo = pi.GetValue(ResList[i], null);

                TempList.Add(oo);

            }



            object[] itm = new object[p.Length];

            //遍历ArrayList向object[]里放数据

            for (int j = 0; j < TempList.Count; j++)

            {

                itm.SetValue(TempList[j], j);

            }

            //将object[]的内容放入DataTable

            TempDT.LoadDataRow(itm, true);

        }

        //返回DataTable

        return TempDT;

    }

    



    #endregion