Question

假设我正在编写ASP.net Web应用程序。

该应用程序的原始设计者使用“PopChart”使一些图像出现在Web应用程序中。其中一个页面上有一个“导出到Excel”按钮。单击该按钮时，页面内容将输出到Excel，如本教程中所示：http://aspalliance.com/articleViewer.aspx?aId=1&pId=。

基本上，它将HTML输出到XLS文件，Excel会对其进行解释。问题是，我需要摆脱PopChart。我用一个输出PNG文件的Web控件替换它（在运行时它可以保存在MemoryStream对象中）。 PopChart引用从公共服务器运行的flash组件; “PopChart”上的数据嵌入在HTML中。

但是，一旦我开始使用输出PNG的Web控件，所有数据都在一个PNG文件中。我看不出有任何方法可以用HTML输出PNG文件。我尝试将数据嵌入img src=...，但Excel不会解释它。 Excel也不能从服务器下载PNG文件;服务器已锁定，Excel无权访问浏览器会话。

我该怎么办？

更新：我在MSDN论坛上找到了以下代码示例：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using DocumentFormat.OpenXml;
using DocumentFormat.OpenXml.Packaging;
using DocumentFormat.OpenXml.Spreadsheet;
using DocumentFormat.OpenXml.Validation;
using DocumentFormat.OpenXml.Drawing.Spreadsheet;

using System.IO;
using System.Drawing;

namespace ConsoleApplication4
{
    class Program
    {
        static void Main(string[] args)
        {
            string sFile = "ExcelOpenXmlWithImage.xlsx";
            if (File.Exists(sFile))
            {
                File.Delete(sFile);
            }
            BuildWorkbook(sFile);
        }

        private static void BuildWorkbook(string filename)
        {
            try
            {
                using (SpreadsheetDocument xl = SpreadsheetDocument.Create(filename, SpreadsheetDocumentType.Workbook))
                {
                    WorkbookPart wbp = xl.AddWorkbookPart();
                    WorksheetPart wsp = wbp.AddNewPart<WorksheetPart>();                                 
                    Workbook wb = new Workbook();
                    FileVersion fv = new FileVersion();
                    fv.ApplicationName = "Microsoft Office Excel";
                    Worksheet ws = new Worksheet();
                    SheetData sd = new SheetData();

                    //string sImagePath = "polymathlogo.png";
                    string sImagePath = @"c:\temp\chartImg.png";
                    DrawingsPart dp = wsp.AddNewPart<DrawingsPart>();
                    ImagePart imgp = dp.AddImagePart(ImagePartType.Png, wsp.GetIdOfPart(dp));
                    using (FileStream fs = new FileStream(sImagePath, FileMode.Open))
                    {
                        imgp.FeedData(fs);
                    }

                    NonVisualDrawingProperties nvdp = new NonVisualDrawingProperties();
                    nvdp.Id = 1025;
                    nvdp.Name = "Picture 1";
                    nvdp.Description = "polymathlogo";
                    DocumentFormat.OpenXml.Drawing.PictureLocks picLocks = new DocumentFormat.OpenXml.Drawing.PictureLocks();
                    picLocks.NoChangeAspect = true;
                    picLocks.NoChangeArrowheads = true;
                    NonVisualPictureDrawingProperties nvpdp = new NonVisualPictureDrawingProperties();
                    nvpdp.PictureLocks = picLocks;
                    NonVisualPictureProperties nvpp = new NonVisualPictureProperties();
                    nvpp.NonVisualDrawingProperties = nvdp;
                    nvpp.NonVisualPictureDrawingProperties = nvpdp;

                    DocumentFormat.OpenXml.Drawing.Stretch stretch = new DocumentFormat.OpenXml.Drawing.Stretch();
                    stretch.FillRectangle = new DocumentFormat.OpenXml.Drawing.FillRectangle();                    

                    BlipFill blipFill = new BlipFill();
                    DocumentFormat.OpenXml.Drawing.Blip blip = new DocumentFormat.OpenXml.Drawing.Blip();
                    blip.Embed = dp.GetIdOfPart(imgp);
                    blip.CompressionState = DocumentFormat.OpenXml.Drawing.BlipCompressionValues.Print;
                    blipFill.Blip = blip;
                    blipFill.SourceRectangle = new DocumentFormat.OpenXml.Drawing.SourceRectangle();
                    blipFill.Append(stretch);

                    DocumentFormat.OpenXml.Drawing.Transform2D t2d = new DocumentFormat.OpenXml.Drawing.Transform2D();
                    DocumentFormat.OpenXml.Drawing.Offset offset = new DocumentFormat.OpenXml.Drawing.Offset();
                    offset.X = 1000;
                    offset.Y = 1000;
                    t2d.Offset = offset;
                    Bitmap bm = new Bitmap(sImagePath);
                    //http://en.wikipedia.org/wiki/English_Metric_Unit#DrawingML
                    //http://stackoverflow.com/questions/1341930/pixel-to-centimeter
                    //http://stackoverflow.com/questions/139655/how-to-convert-pixels-to-points-px-to-pt-in-net-c
                    DocumentFormat.OpenXml.Drawing.Extents extents = new DocumentFormat.OpenXml.Drawing.Extents();
                    extents.Cx = (long)bm.Width * (long)((float)914400 / bm.HorizontalResolution);
                    extents.Cy = (long)bm.Height * (long)((float)914400 / bm.VerticalResolution);
                    bm.Dispose();
                    t2d.Extents = extents;
                    ShapeProperties sp = new ShapeProperties();
                    sp.BlackWhiteMode = DocumentFormat.OpenXml.Drawing.BlackWhiteModeValues.Auto;
                    sp.Transform2D = t2d;
                    DocumentFormat.OpenXml.Drawing.PresetGeometry prstGeom = new DocumentFormat.OpenXml.Drawing.PresetGeometry();
                    prstGeom.Preset = DocumentFormat.OpenXml.Drawing.ShapeTypeValues.Rectangle;
                    prstGeom.AdjustValueList = new DocumentFormat.OpenXml.Drawing.AdjustValueList();
                    sp.Append(prstGeom);
                    sp.Append(new DocumentFormat.OpenXml.Drawing.NoFill());

                    DocumentFormat.OpenXml.Drawing.Spreadsheet.Picture picture = new DocumentFormat.OpenXml.Drawing.Spreadsheet.Picture();
                    picture.NonVisualPictureProperties = nvpp;
                    picture.BlipFill = blipFill;
                    picture.ShapeProperties = sp;

                    Position pos = new Position();
                    pos.X =(Int64) 1000;
                    pos.Y =(Int64) 1000;
                    Extent ext = new Extent();
                    ext.Cx = extents.Cx;
                    ext.Cy = extents.Cy;
                    AbsoluteAnchor anchor = new AbsoluteAnchor();
                    anchor.Position = pos;
                    anchor.Extent = ext;
                    anchor.Append(picture);
                    anchor.Append(new ClientData());
                    WorksheetDrawing wsd = new WorksheetDrawing();
                    wsd.Append(anchor);
                    Drawing drawing = new Drawing();
                    drawing.Id = dp.GetIdOfPart(imgp);

                    wsd.Save(dp);                    

                    ws.Append(sd);
                    ws.Append(drawing);
                    wsp.Worksheet = ws;
                    wsp.Worksheet.Save();
                    Sheets sheets = new Sheets();
                    Sheet sheet = new Sheet();
                    sheet.Name = "Sheet1";
                    sheet.SheetId = 1;
                    sheet.Id = wbp.GetIdOfPart(wsp);
                    sheets.Append(sheet);
                    wb.Append(fv);
                    wb.Append(sheets);

                    xl.WorkbookPart.Workbook = wb;
                    xl.WorkbookPart.Workbook.Save();
                    xl.Close();
                }
            }
            catch (Exception e)
            {
                Console.WriteLine(e.ToString());
                Console.ReadLine();
            }
        }


    }
}

此代码用于创建一个新的Excel电子表格，其中嵌入了图像。但是，我无法修改此代码以将图像放在我想要的电子表格中。（是的，我确实尝试更改偏移量的值。）我还没有成功地将任何文本或数字数据添加到行和列中。

这里有人有这个工作吗？

Answer 1

查看NPOI库，这是一个很棒的库，用于在.Net中生成Excel（和其他Office类型）文档。

通过他们的库，他们有一个示例演示如何将图像加载到Excel中，该文件从文件中读取。由于您可以让POPChart将图像保存为内存流，因此您可以轻松地将其示例修改为从内存流而不是文件中读取。 Excel生成过程的其余部分应该很简单。

Answer 2

要更改图片的位置，您需要更改rowId和columnId。它们充当行和列索引，因此如果你有ColumnId cId = new ColumnId（“2”）;和RowId rId = new RowId（“1”）;您的图像将被放置在C2单元格中。如果使用的是两个CellAnchor，则需要执行两次，一次用于起始索引，一次用于结束索引。

如何使用ASP.net中的图像输出Excel电子表格

2 个答案: