SPListItemCollection.GetDataTable() doesn't return all columns?

Question

I ran into an issue when using the GetDataTable() method. I'm trying to return the default SharePoint column "FileRef" in my results to use. I include it in my SPQuery.ViewFields

Query:

<Where><IsNotNull><FieldRef Name='FileRef'/></IsNotNull></Where>

ViewFields:

<FieldRef Name='Title' /><FieldRef Name='Category' /><FieldRef Name='FileRef' /><FieldRef Name='ID' /><FieldRef Name='Created' />

I can even see it returned in the items.XML but when I call GetDataTable() it is not put in the datatable.

SPListItemCollection items = list.GetItems(spq);
dtItems = items.GetDataTable();

Why isn't GetDataTable working correctly? Am I going to have to write my own conversion method?

Answer 1

You can use this code:Improving SharePoint's SPListItemCollection GetDataTable(), let's get all the fields I need

Answer 2

I'd recommend you a better solution

As SPListItemCollection has Xml proeprty that stores all item data, you can use this XSLT to get data in normal XML format and then create DataSet from XML.

This Idea can be converted to handy extension function:

using System.Data;
using System.Xml;
using System.Xml.Xsl;
using Microsoft.SharePoint;

namespace Balticovo.SharePoint
{
    public static partial class Extensions
    {
        static string sFromRowsetToRegularXmlXslt =
                "<xsl:stylesheet version=\"1.0\" " +
                 "xmlns:xsl=\"http://www.w3.org/1999/XSL/Transform\" " +
                 "xmlns:s=\"uuid:BDC6E3F0-6DA3-11d1-A2A3-00AA00C14882\" " +
                 "xmlns:z=\"#RowsetSchema\">" +

             "<s:Schema id=\"RowsetSchema\"/>" +

             "<xsl:output method=\"xml\" omit-xml-declaration=\"yes\" />" +

             "<xsl:template match=\"/\">" +
              "<xsl:text disable-output-escaping=\"yes\">&lt;rows&gt;</xsl:text>" +
              "<xsl:apply-templates select=\"//z:row\"/>" +
              "<xsl:text disable-output-escaping=\"yes\">&lt;/rows&gt;</xsl:text>" +
             "</xsl:template>" +

             "<xsl:template match=\"z:row\">" +
              "<xsl:text disable-output-escaping=\"yes\">&lt;row&gt;</xsl:text>" +
              "<xsl:apply-templates select=\"@*\"/>" +
              "<xsl:text disable-output-escaping=\"yes\">&lt;/row&gt;</xsl:text>" +
             "</xsl:template>" +

             "<xsl:template match=\"@*\">" +
              "<xsl:text disable-output-escaping=\"yes\">&lt;</xsl:text>" +
              "<xsl:value-of select=\"substring-after(name(), 'ows_')\"/>" +
              "<xsl:text disable-output-escaping=\"yes\">&gt;</xsl:text>" +
              "<xsl:value-of select=\".\"/>" +
              "<xsl:text disable-output-escaping=\"yes\">&lt;/</xsl:text>" +
              "<xsl:value-of select=\"substring-after(name(), 'ows_')\"/>" +
              "<xsl:text disable-output-escaping=\"yes\">&gt;</xsl:text>" +
             "</xsl:template>" +
            "</xsl:stylesheet>";

        public static DataTable GetFullDataTable(this SPListItemCollection itemCollection)
        {
            DataSet ds = new DataSet();

            string xmlData = ConvertZRowToRegularXml(itemCollection.Xml);
            if (string.IsNullOrEmpty(xmlData))
                return null;

            using (System.IO.StringReader sr = new System.IO.StringReader(xmlData))
            {
                ds.ReadXml(sr, XmlReadMode.Auto);

                if (ds.Tables.Count == 0)
                    return null;

                return ds.Tables[0];
            }
        }

        static string ConvertZRowToRegularXml(string zRowData)
        {
            XslCompiledTransform transform = new XslCompiledTransform();
            XmlDocument tidyXsl = new XmlDocument();

            try
            {
                //Transformer
                tidyXsl.LoadXml(Extensions.sFromRowsetToRegularXmlXslt);
                transform.Load(tidyXsl);

                //output (result) writers
                using (System.IO.StringWriter sw = new System.IO.StringWriter())
                {
                    using (XmlTextWriter tw = new XmlTextWriter(sw))
                    {
                        //Source (input) readers
                        using (System.IO.StringReader srZRow = new System.IO.StringReader(zRowData))
                        {
                            using (XmlTextReader xtrZRow = new XmlTextReader(srZRow))
                            {
                                //Transform
                                transform.Transform(xtrZRow, null, tw);
                                return sw.ToString();
                            }
                        }
                    }
                }
            }
            catch
            {
                return null;
            }
        }
    }   
}

By the way, using this method, you will get, if needed, file attachment URL's (SPQuery.IncludeAttachmentUrls = true) not just TRUE/FALSE values as you would get it by using previously mentioned method.

Answer 3

Regarding Janis' answer - I'd remove the bits that do a substring on the ows_ and attempt to remove it, just use:-

"<xsl:value-of select=\"name()\"/>" +

because SP2010 now includes fields such as ETag which don't being with "ows_" and the solution fails. Very good solution otherwise.