c# - 将 Excel 工作簿另存为 HTML - 无法访问 'System.IO.MemoryStream'

Question

我有一些代码，我想将 excel 电子表格转换为 html，这样我就可以将它用作电子邮件的正文。

        Excel.Application excel = new Excel.Application();
        Excel.Workbook workbook = excel.Workbooks.Open(Properties.Settings.Default.FileToSend);

        //Save the workbook to Memory Stream in HTML format
        MemoryStream ms = new MemoryStream();

        // This is the line i have an error on
        workbook.SaveAs(ms, Excel.XlFileFormat.xlHtml); 

        //Seek MemoryStream position to 0
        ms.Position = 0;

        //Define a StreamReader object with the above MemoryStream
        StreamReader sr = new StreamReader(ms);

        //Load the saved HTML from StreamReader now into a string variable
        string strHtmlBody = sr.ReadToEnd();

这是我得到错误的行

        // This is the line i have an error on
        workbook.SaveAs(ms, Excel.XlFileFormat.xlHtml); 

我收到此错误 Cannot access 'System.IO.MemoryStream'。

异常(exception)情况是

System.Runtime.InteropServices.COMException was unhandled
HelpLink=xlmain11.chm
HResult=-2146827284
Message=Cannot access 'System.IO.MemoryStream'.
Source=Microsoft Excel
ErrorCode=-2146827284
StackTrace:
   at Microsoft.Office.Interop.Excel._Workbook.SaveAs(Object Filename, Object FileFormat, Object Password, Object WriteResPassword, Object ReadOnlyRecommended, Object  \ CreateBackup, XlSaveAsAccessMode AccessMode, Object ConflictResolution, Object AddToMru, Object TextCodepage, Object TextVisualLayout, Object Local)
   at Auto_KPI_Email.Program.sendExcel() in E:\My Documents\Visual Studio 2010\Projects\Auto KPI Email\Auto KPI Email\Program.cs:line 71
   at Auto_KPI_Email.Program.Main(String[] args) in E:\My Documents\Visual Studio 2010\Projects\Auto KPI Email\Auto KPI Email\Program.cs:line 19
   at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
   at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.ThreadHelper.ThreadStart()
InnerException: 

有什么建议吗？

Answer 1

作为@GrantWinney pointed out in his answer ，您无法使用可用的 API 将工作簿保存到 MemoryStream。

最好的解决方案是将 HTML 输出到一个临时位置，然后再读回结果。

Excel.Application excel = new Excel.Application();
Excel.Workbook workbook = excel.Workbooks.Open(Properties.Settings.Default.FileToSend);

var temporaryFilepath = Path.ChangeExtension(Path.GetTempFileName(), ".html");
workbook.SaveAs(temporaryFilepath, Excel.XlFileFormat.xlHtml);

var result = File.ReadAllText(temporaryFilepath);

虽然不如将其保存在内存中那么优雅，但在与其他程序集成时，它有时是唯一的解决方案。