【机房重构】C#导出到Excel

电玩女神 2022-06-16 00:30 184阅读 0赞

# 引言 #

在机房重构中很多地方都用到了导出Excel，于是封装了一个类，直接去调用即可，这样简单方便了很多，同时也省去了很多的代码。下面用一个demo来实现导出到Excel

# 实现过程 #

## 1、添加引用 ##

Microsoft Office 15.0 Object Library,Microsoft Excel 15.0 Object Library,如下图

![SouthEast][]

![SouthEast 1][]

## 2、创建一个Excel工作簿 ##

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
        
        //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

## 3、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：

1.  **str**y +worksheet.get\_Range(worksheet.Cells\[1,1\],worksheet.Cells\[rowCount+1,colCount\]).NumberFormat="@";

## 4、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，不过没有解决Excel行数的限制，主要是逻辑问题了

///  /// 导出Excel文件 /// 
        /// 要导入到Excel的数据
        public static string DataSetToExcel2(System.Data.DataSet ds)
        {
            string strFilePath = System.AppDomain.CurrentDomain.BaseDirectory + DateTime.Now.ToString("yyyyMMddhhmmss") + ".xls";
    
            Interop.Excel.Application xlApp = new Interop.Excel.Application();
            Interop.Excel.Workbooks workbooks = xlApp.Workbooks;
            Interop.Excel.Workbook workbook = workbooks.Add(Interop.Excel.XlWBATemplate.xlWBATWorksheet);
    
            try
            {
                if (ds.Tables.Count == 0)
                {
                    return "没有数据导出";
                }
    
                int MaxRowCount = 60000; //一个sheet的最大行数限制，主要考虑到office2003的行数有限
    
                DataTable dt = ds.Tables[0];//数据源
    
                int rowCount = dt.Rows.Count;
                int colCount = dt.Columns.Count;
    
                if (rowCount > 0 && rowCount <= MaxRowCount)
                {
                    object missing = System.Reflection.Missing.Value;
                    Interop.Excel.Worksheet worksheet = (Excel.Worksheet)workbook.Worksheets.Add(missing, missing, missing, missing);//添加一个sheet
                    //Worksheet worksheet = (Worksheet)workbook.Worksheets[i];
                    worksheet.Name = "sheet";
    
    
                    object[,] dataArray = new object[rowCount + 1, colCount];
                    //表头导出
                    for (int j = 0; j < colCount; j++)
                    {
                        dataArray[0, j] = dt.Columns[j].ColumnName.ToString();
                    }
                    //内容导出
                    for (int j = 0; j < rowCount; j++)
                    {
                        for (int k = 0; k < colCount; k++)
                        {
                            dataArray[j + 1, k] = dt.Rows[j][k].ToString();
                        }
                    }
                    worksheet.get_Range(worksheet.Cells[1, 1], worksheet.Cells[rowCount + 1, colCount]).NumberFormat = "@";
                    worksheet.get_Range(worksheet.Cells[1, 1], worksheet.Cells[rowCount + 1, colCount]).Value2 = dataArray;
                }
                else //超过sheet表单的就再创适sheet表单
                {
                    int sheetCount = 1; //sheet表单个数
                    if (rowCount % MaxRowCount == 0)
                    {
                        sheetCount = rowCount / MaxRowCount;
                    }
                    else
                    {
                        sheetCount = rowCount / MaxRowCount + 1;
                    }
    
                    int Flag = 1;
                    for (var m = 0; m < sheetCount; m++)
                    {
                        //添加一个sheet表单
                        object missing1 = System.Reflection.Missing.Value;
                        Excel.Worksheet worksheet1 = (Excel.Worksheet)workbook.Worksheets.Add(missing1, missing1, missing1, missing1);//添加一个sheet
    
                        worksheet1.Name = "第" + (m + 1) + "页sheet";
                        //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
                        if (Flag == sheetCount && (rowCount % MaxRowCount != 0))
                        {
                            int newrowCount = rowCount - ((Flag - 1) * MaxRowCount); //最后一个sheet的数据
                            object[,] dataArray = new object[newrowCount + 1, colCount];
    
                            int RowIndex = 0;
    
    
                            for (int j = 0; j < colCount; j++)
                            {
                                dataArray[0, j] = dt.Columns[j].ColumnName.ToString();
                            }
    
                            int startIndex = (Flag - 1) * MaxRowCount;
                            for (int n = startIndex; n < startIndex + newrowCount; n++)
                            {
                                for (int t = 0; t < colCount; t++)
                                {
                                    dataArray[RowIndex + 1, t] = dt.Rows[n][t].ToString();
                                }
    
                                   RowIndex++;
                            }
                            worksheet1.get_Range(worksheet1.Cells[1, 1], worksheet1.Cells[newrowCount + 1, colCount]).NumberFormat = "@";
                            worksheet1.get_Range(worksheet1.Cells[1, 1], worksheet1.Cells[newrowCount + 1, colCount]).Value2 = dataArray;
    
                        }
                        else
                        {
                            object[,] dataArray = new object[MaxRowCount + 1, colCount];
    
                            int RowIndex = 0;
                            for (int j = 0; j < colCount; j++)
                            {
                                dataArray[0, j] = dt.Columns[j].ColumnName.ToString();
                            }
    
                            int startIndex = (Flag - 1) * MaxRowCount;
                            for (int n = startIndex; n < startIndex + MaxRowCount; n++)
                            {
                                for (int t = 0; t < colCount; t++)
                                {
                                    dataArray[RowIndex + 1, t] = dt.Rows[n][t].ToString();
                                }
                                if (n % 100 == 0)
                                {
    
                                    System.Windows.Forms.Application.DoEvents();
                                }
    
                                RowIndex++;
                            }
                            worksheet1.get_Range(worksheet1.Cells[1, 1], worksheet1.Cells[MaxRowCount + 1, colCount]).NumberFormat = "@";
                            worksheet1.get_Range(worksheet1.Cells[1, 1], worksheet1.Cells[MaxRowCount + 1, colCount]).Value2 = dataArray;
                        }
                        Flag++;
                    }
    
                }
                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;
            }
    
    
            catch
            {
                xlApp.Quit();
                xlApp = null;
                System.Runtime.InteropServices.Marshal.ReleaseComObject(workbooks);
                System.Runtime.InteropServices.Marshal.ReleaseComObject(xlApp);
    
                GC.Collect();
                return "出现异常";
            }
            finally
            {
                System.Runtime.InteropServices.Marshal.ReleaseComObject(workbooks);
                System.Runtime.InteropServices.Marshal.ReleaseComObject(xlApp);
    
                GC.Collect();
            }
    
            return "导出成功，导出文件路径：" + strFilePath;
        }

# 结语 #

导出到Excel的方法有很多，上面小编写的只是其中一种，仅供参考。这个实现其实很简单，理解原理就容易多了。遇到问题多去探索探索，这样会学到很多东西

[SouthEast]: /images/20220616/42b8bc9fafa74192934f57b658a2f8d4.png
[SouthEast 1]: /images/20220616/c03aeb7d9b46434b9cd21d34f6802beb.png