Is reflection really necessary when using the PIAs from another application? "DarrylR" <darrylr[ at ]nospam.com> 16.12.2005 16:11:05 I have discovered (much to my disappointment) that in order to access Word document properties and methods from a Windows Forms application, I have to use reflection instead of calling the methods directly. For example, when I need to access the Word.Document.CustomDocumentProperties collection from VSTO (VBA would be similar), I can use the following syntax: Microsoft.Office.Interop.Word.ApplicationClass objWdClass = new Microsoft.Office.Interop.Word.ApplicationClass(); Microsoft.Office.Interop.Word.Document objDoc = objWdClass.Documents.Add(ref oMissing, ref oMissing, ref oMissing, ref oMissing); string strPropertyName = "ProductId"; object objValue = "theproductid"; Microsoft.Office.Core.DocumentProperties objDocProps = (Microsoft.Office.Core.DocumentProperties)objDoc.CustomDocumentProperties; objDocProps[strPropertyName].Value = objValue; However, the aforementioned code throws a 'cast is invalid' exception when you attempt to cast the object returned by objDoc.CustomDocumentProperties to type DocumentProperties. As a result, I was forced to use the following syntax: object oDocCustomProps = objDoc.CustomDocumentProperties; Type typeDocCustomProps = oDocCustomProps.GetType(); object oCustomProp = typeDocCustomProps.InvokeMember("Item", BindingFlags.Default | BindingFlags.GetProperty, null, oDocCustomProps, new object[] {strPropertyName}); typeDocCustomProps.InvokeMember("Item", BindingFlags.Default | BindingFlags.SetProperty, null, oDocCustomProps, new object[] {strPropertyName, objValue} ); I realize that the objects need to be marshalled across processes. But is it really necessary to use reflection? Is there anything that would make this easier? Any information/advice would be greatly appreciated. Thanks, Darryl R.

Re: Is reflection really necessary when using the PIAs from another application? Cindy M -WordMVP- <C.Meister-C[ at ]hispeed.ch> 19.12.2005 17:36:36 Hi DarrylR, You only need to use late-binding (what you're calling reflection) for things that are late bound the object library you're working with. In the case of Word, the custom document properties are late-bound into Word, so you can't access them directly through the object model. The same goes for WordBasic commands and the Word dialog box arguments. Visual Basic can do this, if Option Strict is not on. If you don't want to go the long route, then you could create a VB project class with Option Strict off and import that into your C# project. Then use the methods in the VB project to work with the custom document properties. Other than that, you can set up a "library" of methods so that you don't have to rewrite the reflection code every time you want to access them. [Quoted Text] > I have discovered (much to my disappointment) that in order to access Word > document properties and methods from a Windows Forms application, I have to > use reflection instead of calling the methods directly. For example, when I > need to access the Word.Document.CustomDocumentProperties collection from > VSTO (VBA would be similar), I can use the following syntax: > > Microsoft.Office.Interop.Word.ApplicationClass objWdClass = > new Microsoft.Office.Interop.Word.ApplicationClass(); > Microsoft.Office.Interop.Word.Document objDoc = > objWdClass.Documents.Add(ref oMissing, ref oMissing, ref oMissing, ref > oMissing); > string strPropertyName = "ProductId"; > object objValue = "theproductid"; > Microsoft.Office.Core.DocumentProperties objDocProps = > (Microsoft.Office.Core.DocumentProperties)objDoc.CustomDocumentProperties; > objDocProps[strPropertyName].Value = objValue; > > However, the aforementioned code throws a 'cast is invalid' exception when > you attempt to cast the object returned by objDoc.CustomDocumentProperties > to type DocumentProperties. As a result, I was forced to use the following > syntax: > > object oDocCustomProps = objDoc.CustomDocumentProperties; > Type typeDocCustomProps = oDocCustomProps.GetType(); > object oCustomProp = typeDocCustomProps.InvokeMember("Item", > BindingFlags.Default | > BindingFlags.GetProperty, > null, oDocCustomProps, > new object[] {strPropertyName}); > > typeDocCustomProps.InvokeMember("Item", > BindingFlags.Default | > BindingFlags.SetProperty, > null, oDocCustomProps, > new object[] {strPropertyName, objValue} ); > > I realize that the objects need to be marshalled across processes. But is it > really necessary to use reflection? Is there anything that would make this > easier? Any information/advice would be greatly appreciated. > Cindy Meister INTER-Solutions, Switzerland http://homepage.swissonline.ch/cindymeister (last update Jun 8 2004) http://www.word.mvps.org This reply is posted in the Newsgroup; please post any follow question or reply in the newsgroup and not by e-mail :-)

Re: Is reflection really necessary when using the PIAs from another application? "DarrylR" <darrylr[ at ]nospam.com> 21.12.2005 18:04:27 Thanks, Cindy! -DKR "Cindy M -WordMVP-" <C.Meister-C[ at ]hispeed.ch> wrote in message news:VA.0000b4c4.014f1b0c[ at ]speedy... [Quoted Text] > Hi DarrylR, > > You only need to use late-binding (what you're calling reflection) for things > that are late bound the object library you're working with. In the case of > Word, the custom document properties are late-bound into Word, so you can't > access them directly through the object model. The same goes for WordBasic > commands and the Word dialog box arguments. > > Visual Basic can do this, if Option Strict is not on. > > If you don't want to go the long route, then you could create a VB project > class with Option Strict off and import that into your C# project. Then use > the methods in the VB project to work with the custom document properties. > > Other than that, you can set up a "library" of methods so that you don't have > to rewrite the reflection code every time you want to access them.