• 【原创】WinForm导出数据到EXCEL(根据微软的Excel插件)


    导出数据到Excel算是一个比较成熟的技术点了,现在的方法也比较,比如:可以用微软的EXCEL组件,第三方开源组件(NPOI,MyXls等等。)
    今天我就首先说一下微软的EXCEL组件

    在开发过程中可能出现一系列的问题

    (1)Excel行数的限制,office2003的行数为65536行。如果超过这个行数应该再来一个sheet

    (2)导出数据慢的问题,如果数据量比较小可能一般的程序逻辑看不出来它的性能问题,当我们导出的数据很多时,应该选择什么方案解决

    (3)  导出的格式问题,一些导出到Excel中的格式可能需要计算,那么它就是数字型的

    本例先简单说一下实现逻辑,不多说,直接上代码:

    (1)添加引用

    (2)可以写代码了

    第一步:创建一个Excel工作薄

               Interop.Excel.Application xlApp = new Interop.Excel.Application(); ////建立一个Excel.Application的新进程

                Excel.Workbooks workbooks = xlApp.Workbooks; //工作薄的创建

                Excel.Workbook workbook = workbooks.Add(Excel.XlWBATemplate.xlWBATWorksheet); //工作表sheet的创建

    【当然也可以用下面的代码创建工作表sheet】

          object missing = System.Reflection.Missing.Value;

                  Excel.Worksheet worksheet = (Excel.Worksheet)workbook.Worksheets.Add(missing, missing, missing, missing);//添加一个sheet

    第二步:插入数据

                            object[,] dataArray = new object[rowCount, colCount];

                            for (int j = 0; j < rowCount; j++)

                            {

                                for (int k = 0; k < colCount; k++)

                                {

                                    dataArray[j, k] = drs[j][k].ToString();

                                }

                            }

                            worksheet.get_Range(worksheet.Cells[1, 1], worksheet.Cells[rowCount, colCount]).Value2 = dataArray;

    注:这种方式是把一个二维数组的数据插入到Excel的固定区域,不用一个单元格一个单元格的插入,速度快很多。解决了导出数据慢的问题

    可能你保存的时候定义Excel的格式,可以用NumberFormat来定义,例如:

    worksheet.get_Range(worksheet.Cells[1, 1], worksheet.Cells[rowCount + 1, colCount]).NumberFormat = "@";

    第三步:保存Excel

     workbook.SaveAs(strFilePath, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Excel.XlSaveAsAccessMode.xlNoChange, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing);
                    workbook.Close(true, Type.Missing, Type.Missing);
                    workbook = null;

     

    以上是最简洁的方式,不过第一个问题还没有给解决,直接上代码吧。主要是逻辑问题了。没有什么技术难点。

      1 /// <summary>
      2         /// 导出Excel文件
      3         /// </summary>
      4         /// <param name="ds">要导入到Excel的数据</param>
      5         public static string DataSetToExcel2(System.Data.DataSet ds)
      6         {
      7             string strFilePath = System.AppDomain.CurrentDomain.BaseDirectory + DateTime.Now.ToString("yyyyMMddhhmmss") + ".xls";
      8 
      9             Interop.Excel.Application xlApp = new Interop.Excel.Application();
     10             Interop.Excel.Workbooks workbooks = xlApp.Workbooks;
     11             Interop.Excel.Workbook workbook = workbooks.Add(Interop.Excel.XlWBATemplate.xlWBATWorksheet);
     12 
     13             try
     14             {
     15                 if (ds.Tables.Count == 0)
     16                 {
     17                     return "没有数据导出";
     18                 }
     19 
     20                 int MaxRowCount = 60000; //一个sheet的最大行数限制,主要考虑到office2003的行数有限
     21 
     22                 DataTable dt = ds.Tables[0];//数据源
     23 
     24                 int rowCount = dt.Rows.Count;
     25                 int colCount = dt.Columns.Count;
     26 
     27                 if (rowCount > 0 && rowCount <= MaxRowCount)
     28                 {
     29                     object missing = System.Reflection.Missing.Value;
     30                     Interop.Excel.Worksheet worksheet = (Excel.Worksheet)workbook.Worksheets.Add(missing, missing, missing, missing);//添加一个sheet
     31                     //Worksheet worksheet = (Worksheet)workbook.Worksheets[i];
     32                     worksheet.Name = "sheet";
     33 
     34 
     35                     object[,] dataArray = new object[rowCount + 1, colCount];
     36                     //表头导出
     37                     for (int j = 0; j < colCount; j++)
     38                     {
     39                         dataArray[0, j] = dt.Columns[j].ColumnName.ToString();
     40                     }
     41                     //内容导出
     42                     for (int j = 0; j < rowCount; j++)
     43                     {
     44                         for (int k = 0; k < colCount; k++)
     45                         {
     46                             dataArray[j + 1, k] = dt.Rows[j][k].ToString();
     47                         }
     48                     }
     53                     worksheet.get_Range(worksheet.Cells[1, 1], worksheet.Cells[rowCount + 1, colCount]).NumberFormat = "@";
     54                     worksheet.get_Range(worksheet.Cells[1, 1], worksheet.Cells[rowCount + 1, colCount]).Value2 = dataArray;
     55                 }
     56                 else //超过sheet表单的就再创适sheet表单
     57                 {
     58                     int sheetCount = 1; //sheet表单个数
     59                     if (rowCount % MaxRowCount == 0)
     60                     {
     61                         sheetCount = rowCount / MaxRowCount;
     62                     }
     63                     else
     64                     {
     65                         sheetCount = rowCount / MaxRowCount + 1;
     66                     }
     67 
     68                     int Flag = 1;
     69                     for (var m = 0; m < sheetCount; m++)
     70                     {
     71                         //添加一个sheet表单
     72                         object missing1 = System.Reflection.Missing.Value;
     73                         Excel.Worksheet worksheet1 = (Excel.Worksheet)workbook.Worksheets.Add(missing1, missing1, missing1, missing1);//添加一个sheet
     74 
     75                         worksheet1.Name = "" + (m + 1) + "页sheet";
     76                         //如果是最后一个sheet的话 并且最后一个sheet表单数据不等于60000
     77                         if (Flag == sheetCount && (rowCount % MaxRowCount != 0))
     78                         {
     79                             int newrowCount = rowCount - ((Flag - 1) * MaxRowCount); //最后一个sheet的数据
     80                             object[,] dataArray = new object[newrowCount + 1, colCount];
     81 
     82                             int RowIndex = 0;
     83 
     84 
     85                             for (int j = 0; j < colCount; j++)
     86                             {
     87                                 dataArray[0, j] = dt.Columns[j].ColumnName.ToString();
     88                             }
     89 
     90                             int startIndex = (Flag - 1) * MaxRowCount;
     91                             for (int n = startIndex; n < startIndex + newrowCount; n++)
     92                             {
     93                                 for (int t = 0; t < colCount; t++)
     94                                 {
     95                                     dataArray[RowIndex + 1, t] = dt.Rows[n][t].ToString();
     96                                 }
     97 
     98                                    RowIndex++;
    103                             }
    104                             worksheet1.get_Range(worksheet1.Cells[1, 1], worksheet1.Cells[newrowCount + 1, colCount]).NumberFormat = "@";
    105                             worksheet1.get_Range(worksheet1.Cells[1, 1], worksheet1.Cells[newrowCount + 1, colCount]).Value2 = dataArray;
    106 
    107                         }
    108                         else
    109                         {
    110                             object[,] dataArray = new object[MaxRowCount + 1, colCount];
    111 
    112                             int RowIndex = 0;
    113                             for (int j = 0; j < colCount; j++)
    114                             {
    115                                 dataArray[0, j] = dt.Columns[j].ColumnName.ToString();
    116                             }
    117 
    118                             int startIndex = (Flag - 1) * MaxRowCount;
    119                             for (int n = startIndex; n < startIndex + MaxRowCount; n++)
    120                             {
    121                                 for (int t = 0; t < colCount; t++)
    122                                 {
    123                                     dataArray[RowIndex + 1, t] = dt.Rows[n][t].ToString();
    124                                 }
    125                                 if (n % 100 == 0)
    126                                 {
    127 
    128                                     System.Windows.Forms.Application.DoEvents();
    129                                 }
    130 
    131                                 RowIndex++;
    132                             }
    133                             worksheet1.get_Range(worksheet1.Cells[1, 1], worksheet1.Cells[MaxRowCount + 1, colCount]).NumberFormat = "@";
    134                             worksheet1.get_Range(worksheet1.Cells[1, 1], worksheet1.Cells[MaxRowCount + 1, colCount]).Value2 = dataArray;
    135                         }
    136                         Flag++;
    137                     }
    138 
    139                 }
    140                 workbook.SaveAs(strFilePath, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Excel.XlSaveAsAccessMode.xlNoChange, Type.Missing, Type.Missing, Type.Missing, Type.Missing, Type.Missing);
    141                 workbook.Close(true, Type.Missing, Type.Missing);
    142                 workbook = null;
    143             }
    144 
    145 
    146             catch
    147             {
    148                 xlApp.Quit();
    149                 xlApp = null;
    150                 System.Runtime.InteropServices.Marshal.ReleaseComObject(workbooks);
    151                 System.Runtime.InteropServices.Marshal.ReleaseComObject(xlApp);
    152 
    153                 GC.Collect();
    154                 return "出现异常";
    155             }
    156             finally
    157             {
    158                 System.Runtime.InteropServices.Marshal.ReleaseComObject(workbooks);
    159                 System.Runtime.InteropServices.Marshal.ReleaseComObject(xlApp);
    160 
    161                 GC.Collect();
    162             }
    163 
    164             return "导出成功,导出文件路径:" + strFilePath;
    165         }

    头一次写文章,主要记录自己开发过程的点点滴滴,如果能帮助大家一点最好,哈哈。

     转载的请注原创地址,谢谢。

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  • 原文地址:https://www.cnblogs.com/yxhblog/p/2534945.html
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