Office Interop在Windows服务中不起作用

Question

Office Interop在Windows服务中不起作用

ble*_*ter 5 vsto windows-services office-interop c#-4.0

我对Microsoft Office有一个非常奇怪的问题.

我有一个公共库,其唯一目的是打开传递给它的任何word文档文件类型(通过完整文件路径...)并将打开的word文档保存为pdf文件.

奇怪的问题是,如果我从Windows服务中使用该库,每当它尝试打开word文档时,我都会得到一个null ...也就是说,word文档永远不会被打开.

但是,如果我从WPF或Windows Form应用程序中使用库,我从来没有遇到任何问题.我知道线程存在问题,(单线程公寓)但是我不知道如何修复它以解决Windows服务问题.:( :( :(

我将不胜感激任何帮助!我得到的错误是以下内容:

异常消息:{"对象引用未设置为对象的实例."}(参考word文档).内在例外:无效; HResult:-2147467261.数据:ListDictionaryInternal有0个条目; 堆栈跟踪:位于c:\ Project Files ...\DocumentConverter.cs中的DocumentConverter.ToPdf(String currentWorkingFolderPath,String pathToDocumentToConvert):第209行

所以这是库函数.它需要Microsoft Office引用,该引用由Visual Studio Tools for Office创建.

private string ToPDF(string currentWorkingFolderPath, string pathToDocumentToConvert)
{
    string temporaryPdfFolderPath = Path.GetFullPath(currentWorkingFolderPath + "\\pdf\\");
    string temporaryPdfFilePath = Path.GetFullPath(temporaryPdfFolderPath + "\\pdffile.pdf");

    if (!FileSystem.CreateDirectory(temporaryPdfFolderPath))
    {
        return null;
    }

    try
    {
        Microsoft.Office.Interop.Word.Application wordApplication = new Microsoft.Office.Interop.Word.Application();

        object objectMissing = System.Reflection.Missing.Value;

        wordApplication.Visible = false;
        wordApplication.ScreenUpdating = false;

        FileInfo wordFile = new FileInfo(pathToDocumentToConvert);

        Object fileName = (Object)wordFile.FullName;

        // This is where it breaks when called from windows service. Use the dummy value as a placeholder for optional arguments
        Document wordDocument = wordApplication.Documents.Open(ref fileName, ref objectMissing,            
            true, ref objectMissing, ref objectMissing, ref objectMissing, ref objectMissing,            
            ref objectMissing, ref objectMissing, ref objectMissing, ref objectMissing, ref objectMissing,            
            ref objectMissing, ref objectMissing, ref objectMissing, ref objectMissing);



        object outputFileName = (object)temporaryPdfFilePath;
        object fileFormat = WdSaveFormat.wdFormatPDF ;

        // Save document into PDF Format
        wordDocument.SaveAs(ref outputFileName,
            ref fileFormat, ref objectMissing, ref objectMissing,
            ref objectMissing, ref objectMissing, ref objectMissing, ref objectMissing,
            ref objectMissing, ref objectMissing, ref objectMissing, ref objectMissing,
            ref objectMissing, ref objectMissing, ref objectMissing, ref objectMissing);

        // Close the Word document, but leave the Word application open.
        // doc has to be cast to type _Document so that it will find the
        // correct Close method.                
        object saveChanges = WdSaveOptions.wdDoNotSaveChanges;
        ((_Document)wordDocument).Close(ref saveChanges, ref objectMissing, ref objectMissing);

        wordDocument = null;

        // word has to be cast to type _Application so that it will find
        // the correct Quit method.
        ((Microsoft.Office.Interop.Word._Application)wordApplication).Quit(ref objectMissing, ref objectMissing, ref objectMissing);

        wordApplication = null;

    }
    catch (Exception ex)
    {
        //logging code
        return null;
    }

    return temporaryPdfFilePath;
}

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