C#获取Word文档作者和主题

    Word.Application oWord;
            Word._Document oDoc;
            object oMissing = Missing.Value;
            object docBuiltInProps;

            object Source = @"DocPath";
            object Unknown =Type.Missing;
            oWord = new Word.Application();
            
            try
            {
                oDoc = oWord.Documents.Open(ref Source,ref Unknown, 
                    ref Unknown,ref Unknown,ref Unknown, 
                    ref Unknown,ref Unknown,ref Unknown, 
                    ref Unknown,ref Unknown,ref Unknown, 
                    ref Unknown );

                docBuiltInProps = oDoc.BuiltInDocumentProperties;
            
                Type typeDocBuiltInProps = docBuiltInProps.GetType();
            
            
                //获取作者
                string index = "Author";
                string propsValue;
                
                object docAuthor = typeDocBuiltInProps.InvokeMember("Item", 
                    BindingFlags.Default | 
                    BindingFlags.GetProperty, 
                    null,docBuiltInProps, 
                    new object[] {index} );
            
                Type typeDocAuthorProp = docAuthor.GetType();
                
                propsValue = typeDocAuthorProp.InvokeMember("Value", 
                    BindingFlags.Default |
                    BindingFlags.GetProperty,
                    null,docAuthor,
                    new object[] {} ).ToString();
                
                MessageBox.Show( propsValue,"Author" );

                //获取主题
                index = "Subject";
                propsValue = "The Subject";
                
                object docSubjectProp = typeDocBuiltInProps.InvokeMember("Item", 
                    BindingFlags.Default | 
                    BindingFlags.GetProperty, 
                    null,docBuiltInProps, 
                    new object[] {index} );
            
                Type typeDocSubjectProp = docSubjectProp.GetType();
                
                propsValue = typeDocSubjectProp.InvokeMember("Value", 
                    BindingFlags.Default |BindingFlags.GetProperty,
                    null,docSubjectProp,
                    new object[] {} ).ToString();
                
                MessageBox.Show( propsValue,"Subject" );

            }
            finally
            {
                //关闭word进程
                object save = false;
            
                oWord.Quit(ref save,ref Unknown,ref Unknown);
            
                System.Runtime.InteropServices.Marshal.ReleaseComObject(oWord);    
            }