This past week I was implementing an "evolving" solution for a client that uses BDC and SPQuery and ran into some difficulty using SPQuery against a document library containing folders. Bottom line: assign "recursive" kwa sifa mtazamo wa swala.

Yangu mazingira:

• Jumatatu, Mimi upload hati na ugavi baadhi ya data meta.
• Wiki iliyofuata, I upload a new document. Much of this new document’s meta data is based on the document I uploaded on Monday (which we call the "master document").
• Tumeunda huduma ya mtandao façade ambayo hutoa interface BDC-kirafiki na orodha hivyo kwamba watumiaji urahisi Machapisho kwamba hati Jumatatu kupitia tafuta cheo.
• A BDC data column provides a friendly user interface. (Hii ni sehemu ya jaribio yangu katika kutumia BDC kwa safu zaidi ya kirafiki Lookup).

mwisho BDC façade huduma anatumia swala kama hii kufanya lookup:

 // Kutumika U2U chombo ili kusaidia katika kuzalisha hii hoja CAML.
      oQuery.Query =
        "<Ambapo>";

      kama (titleFilter.Length > 0)
        oQuery.Query   =
          "  <Na>";

      oQuery.Query   =
        "    <Na>" +
        "      <Geq>" +
        "        <FieldRef Name=\"DocumentId\" />" +
        "        <Value Type=\"Text\">" + MinID + "</Thamani>" +
        "      </Geq>" +
        "      <Leq>" +
        "        <FieldRef Name=\"DocumentId\" />" +
        "        <Value Type=\"Text\">" + maxId + "</Thamani>" +
        "      </Leq>" +
        "    </Na>";

      kama (titleFilter.Length > 0)
        oQuery.Query   =
          "    <Ina>" +
          "      <FieldRef Name=\"Title\" />" +
          "      <Value Type=\"Text\">" + titleFilter + "</Thamani>" +
          "    </Ina>" +
          "  </Na>";
      oQuery.Query   =
        "</Ambapo>";

Wakati wa hatua ya awali ya maendeleo, this worked great. Hata hivyo, sisi ilianzisha folders katika saraka ya kutatua baadhi ya matatizo na ghafla, my BDC picker wouldn’t return any results. I tracked this down to the fact that the SPQuery would never return any results. We used folders primarily to allow multiple files with the same name to be uploaded but with different meta data. When the file is uploaded, sisi kujenga folder msingi ID bidhaa orodha na kisha kuondoka faili huko (Niliandika kuhusu kwamba hapa; tulikuwa na mchanganyiko matokeo na mfumo huu lakini kwa ujumla, ni kazi vizuri). The user don’t care about folders and in fact, don’t really understand that there are any folders. We have configured all the views on the library to show items without regard to folders.

I hit this problem twice as the technical implementation evolved and solved it differently each time. The first time, I wasn’t using the CONTAINS operator in the query. Without a CONTAINS operator, I was able to solve the problem by specifying the view on the SPQuery’s contructor. Instead of using the default constructor:

SPList oList = web.Lists["Documents"];

SPQuery oQuery = mpya SPQuery();

Mimi badala kutumika kuujenga kwamba maalum mtazamo:

SPList oList = web.Lists["Documents"];

SPQuery oQuery = mpya SPQuery(oList.Views["All Documents"]);

Kwamba kutatuliwa tatizo na mimi kuanza kupata matokeo yangu.

I then added the CONTAINS operator into the mix and it broke again. It turns out that the CONTAINS operator, hivyo mbali kama naweza kuwaambia, haifanyi kazi kwa lengo njia ile ile kama GEQ rahisi / LEQ operators. I did some searching and learned that the query’s ViewAttributes should be set to "Recursive", kama katika:

oQuery.ViewAttributes = "Scope=\"Recursive\"";

That solved the problem for CONTAINS. Kwa kweli, hii pia kutatuliwa tafuta yangu ya awali tatizo na kama alikuwa maalum sifa kujirudia mara ya kwanza, Mimi bila kuwa na kukimbia katika suala tena.

ukweli kwamba SPQuery maoni makao kazi kwa waendeshaji baadhi (GEQ/LEQ) na si watu wengine (Ina), pamoja na ukweli kwamba KPIs hawaonekani kazi wakati wote na maktaba hati folder zenye inaongoza mimi kuamini kwamba SPQuery ina baadhi ya masuala orthogonality.

Shukrani maalum:

• folks mzuri katika U2U na chombo yao swala.
• Michael Hoffer kubwa "kujifunza kwa kutenda" blog post, maoni na majibu.

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