无法在Microsoft.Office.Interop.Word中投射COM（Word 2016）

Question

我有一些代码可以打印docx文档：

Microsoft.Office.Interop.Word.Application wordInstance = new Microsoft.Office.Interop.Word.Application();
FileInfo wordFile = new FileInfo("1.docx");
object fileObject = wordFile.FullName;
object oMissing = System.Reflection.Missing.Value;
Microsoft.Office.Interop.Word.Document doc = wordInstance.Documents.Open(ref fileObject);
doc.Activate();
doc.PrintOut(oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, 
    oMissing, oMissing, oMissing, oMissing);

但我在wordInstance.Documents.Open（）上收到异常：

  

无法将'microsoft.Office.Interop.Word.ApplicationClass'类型的COM对象强制转换为'microsoft.Office.Interop.Word.Application'“

我有Word 2016和Microsoft.Office.Interop.Word版本15.0.0.0。

我该如何解决这个问题？

Answer 1

我找到了解决方案：

dynamic wordInstance = new Microsoft.Office.Interop.Word.Application();
FileInfo wordFile = new FileInfo("2.docx");
object fileObject = wordFile.FullName;
object oMissing = System.Reflection.Missing.Value;
dynamic doc = wordInstance.Documents.Open(ref fileObject);
doc.Activate();
doc.PrintOut(oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing);

创建WordApplication并打开wordInstance.Documents.Open时，我必须使用动态

感谢MickyD提出了一个好主意！