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//
// System.Web.Util.DataSourceResolver
//
// Authors:
// Ben Maurer (bmaurer@novell.com)
//
// (C) 2005 Novell, Inc (http://www.novell.com)
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
//
// This is from
// _Developing Microsoft ASP.NET Server Controls and Components_ (Kothari, Datye)
// Listing 20-3 "GetDataSource" (page 564)
//
using System.Collections;
using System.ComponentModel;
namespace System.Web.Util {
class DataSourceResolver
{
DataSourceResolver () {}
public static IEnumerable ResolveDataSource (object o, string data_member)
{
IEnumerable ds;
ds = o as IEnumerable;
if (ds != null)
return ds;
IListSource ls = o as IListSource;
if (ls == null)
return null;
IList member_list = ls.GetList ();
if (! ls.ContainsListCollection)
return member_list;
ITypedList tl = member_list as ITypedList;
if (tl == null)
return null;
PropertyDescriptorCollection pd = tl.GetItemProperties (new PropertyDescriptor [0]);
if (pd == null || pd.Count == 0)
throw new HttpException ("The selected data source did not contain any data members to bind to");
PropertyDescriptor member_desc = data_member == "" ?
pd [0] :
pd.Find (data_member, true);
if (member_desc != null)
ds = member_desc.GetValue (member_list [0]) as IEnumerable;
if (ds == null)
throw new HttpException ("A list corresponding to the selected DataMember was not found");
return ds;
}
}
}
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