I was working on a feature last week that would add some event receivers to a specific list instance. (Blogged mé beagán faoi go glacadóir liosta anseo).

Ag baint úsáide as an líne ordaithe, Raibh mé in ann a shuiteáil an gné gan aon earráid (ach féach thíos le haghaidh an earráid i bhfolach). When I tried to deploy the feature on the site, MOSS complained of a "FileNotFoundException" earráid. This blog entry describes how I solved it.

This is the error that MOSS showed me in the web browser:

Feature ‘b2cb42e3-4f0a-4380-aaba-1ef9cd526f20’ could not be installed because the loading of event receiver assembly "xyzzyFeatureReceiver_0" failed: System.IO.FileNotFoundException: Could not load file or assembly ‘xyzzyFeatureReceiver_0’ nó ceann dá spleáchais. The system cannot find the file specified. File name: ‘xyzzyFeatureReceiver_0’ at System.Reflection.Assembly.nLoad(AssemblyName ainm comhaid, Codebase Teaghrán, AssemblySecurity Fianaise, Tionól locationHint, StackCrawlMark& ithir Stack, Boole throwOnFileNotFound, ForIntrospection Boole) at System.Reflection.Assembly.InternalLoad(AssemblyName assemblyRef, AssemblySecurity Fianaise, StackCrawlMark& ithir Stack, ForIntrospection Boole) at System.Reflection.Assembly.InternalLoad(String assemblyString, AssemblySecurity Fianaise, StackCrawlMark& ithir Stack, ForIntrospection Boole) at System.Reflection.Assembly.Load(String assemblyString) at Microsoft.SharePoint.Administration.SPFeatureDefinition.get_ReceiverObject() WRN: Assembly binding logging is turned OFF. To enable assembly bind failure logging, set the registry value [HKLM\Software\Microsoft\Fusion!EnableLog] (DWORD) go 1. Tabhair faoi deara: There is some performance penalty associated with assembly bind failure logging. To turn this feature off, remove the registry value [HKLM\Software\Microsoft\Fusion!EnableLog]. Troubleshoot issues with Windows SharePoint Services.

I know how to deliberately cause that error: don’t install the assembly in the GAC. Ach, it was in the GAC. I normally install assemblies into the GAC by dragging them into the c:\windows\assembly folder using windows explorer. I’ve never felt 100% comfortable doing that because I always thought that gacutil existed for a reason … so I tried that. It made no difference.

I searched the Internets and found this post: http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=2243677&SiteID=1

The poster happened to be using the same root bit of code (from the Inside WSS book from this list) so that was a hopeful sign. Mar sin féin, the suggestion of decorating the assembly with an [assembly: ] directive didn’t make sense to me. I tried it anyway and I was right. It made no difference.

Then I noticed that my class definition was not public. I made it public and that made no difference.

Ar Aghaidh, I went to the trouble of enabling the "assembly bind failure log" (following the helpful and accurate instructions provided) and this is where things started to get interesting. That log shows me that the runtime is searching everywhere on that server for my assembly. It even appears to be searching for it in my medicine cabinet. Ach … it won’t search for it in the GAC.

I put on my winter jacket and go searching the Internets again and find that someone has had this problem too. The lengthy discussion in that posting peters off into nothing and I can’t find a solution.

I move my assembly into one of the places the log claims it’s searching and I make a little more progress. I’m rewarded with a new error in the browser when I try to activate the feature:

Failed to create feature receiver object from assembly "xyzzyFeatureReceiver_0", type "Conchango.xyzzyFeatureReceiver" for feature b2cb42e3-4f0a-4380-aaba-1ef9cd526f20: System.ArgumentNullException: Ní féidir luach a bheith ar neamhní. Ainm Paraiméadar: cineál at System.Activator.CreateInstance(Type type, Boolean nonPublic) at System.Activator.CreateInstance(Type type) at Microsoft.SharePoint.Administration.SPFeatureDefinition.get_ReceiverObject() Troubleshoot issues with Windows SharePoint Services.

Time for one last trip to the Internets!

This time I find out, predictably enough, that MOSS issues this error because the assembly is not in GAC.

Ba mhaith liom a fháil ar rud éigin as dhearfach seo agus iarracht a bhraitheann ar beag bródúil go chruthaigh mé an Teifeacha de tionóil MSIL, but it’s not working. I’m just plain annoyed. I find myself muttering "chicken or the egg" faoi ​​mo anáil.

I finally decide to punt. I create an entirely new project and copy/paste the code from the incredible-cloaked-from-the-GAC-assembly non-working project over to this new project. (I look for a build flag called something like "hide from assembly binding if installed in the GAC" ach ní féidir teacht ar aon).

Shuiteáil mé an gné agus a ghníomhachtú é agus … oibríonn sé! Mar sin,, tar éis an tsaoil go, I had to basically ‘reboot’ my project. This is another reason why I hate computers.

I did learn something useful from this. I had been installing features using the stsadm command line all day long and been using the "-force" option out of habit. Ar chúis éigin, I did not use the -force option when I installed the new project. An uair seo, Rinne mé i ndáiríre, truly forget to copy this new project’s assembly into the GAC. Mar thoradh air sin, I received that "FielNotFoundException" earráid. An uair seo, Fuair ​​mé é ó stsadm, not when I tried to activate the feature via the web browser. Mar sin,, -force actually plays two roles. It allows you to re-install an existing feature. It also allows you to install a buggy feature that cannot work at runtime by suppressing the error. It probably says as much in the help somewhere but I never noticed it.

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Suas chun dáta: This works but there are significant limitations which are described in the comments. This may still be useful in some cirumstances.

Suas chun dáta 2: I mo tionscadal reatha, users always upload documents. Mar thoradh air sin, I don’t run into a problem where MS Word is running and thinks that the file was renamed on it. I did run into a problem, "the file was modified by someone else" and solved this via a simple semaphore type flag. Users need to change a meta data field from its default value to something else. The itemupdated() Breathnaíonn an glacadóir le haghaidh luach bailí ann roimh iarbhír ag comhlíonadh a athainmniú agus ó shin, I have not had any problems. Your mileage may vary.

I have a client requirement to change the name of files uploaded to a specific document library to conform with a particular naming convention. The API does not provide a "rename()" modh. Ina áit sin, úsáidimid "MoveTo(…)". Here is a minimal bit of code to accomplish this:

 poiblí shárú neamhní ItemAdded(SPItemEventProperties airíonna)
        {
            SPFile f = properties.ListItem.File;

            f.MoveTo(properties.ListItem.ParentList.RootFolder.Url + "/xyzzy.doc");
            f.Update();

        }

The only tricky bit is the "properties.ListItem.ParentList.RootFolder.Url". The MoveTo() method requires a URL. That mashed up string points me to the root folder of my current document library. This allows me to avoid any hard coding in my event receiver.

Is é seo an leagan níos úsáidí a dhéanann an rud céanna, but assigns the name of the file to "Title":

 poiblí shárú neamhní ItemAdded(SPItemEventProperties airíonna)
        {
            DisableEventFiring();

            // An teideal na míre seo a shannadh do ainm an chomhaid féin.
 // NÓTA: Ní mór an tasc a chur i bhfeidhm roimh linn a mhodhnú an comhad féin.
 // Ag glaoch ar thabhairt cothrom le dáta() ar an SPFile is cosúil a dhéanamh neamhbhailí na maoine i
 // ciall éigin.  Updates to "Title" Theip ar go dtí an t-athrú (agus nuashonrú() glaoch)
 // Bhí ar athraíodh a ionad i os comhair an t-athrú ar ainm an chomhaid.
            properties.ListItem["Title"] = Properties.ListItem.File.Name;

            properties.ListItem.Update();

            SPFile f = properties.ListItem.File;

            // Faigh an síneadh ar an gcomhad.  Ní mór dúinn go déanaí.
 teaghrán spfileExt = nua Eolas Comhad(f.Name).Síneadh;

            // Athainmnigh an comhad leis an mír den liosta ID agus úsáid a bhaint as an síneadh comhad a choinneáil
 // an chuid sin de sé slán.
            f.MoveTo(properties.ListItem.ParentList.RootFolder.Url +
                "/" + properties.ListItem["ID"] + spfileExt);

            // Tiomantas an t-aistriú.
            f.Update();

            EnableEventFiring();
        }