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//------------------------------------------------------------------------------
// <copyright file="ReadOnlyDataSource.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//------------------------------------------------------------------------------
namespace System.Web.UI.WebControls {
using System;
using System.Collections;
using System.ComponentModel;
using System.Web;
using System.Web.UI;
using System.Web.Util;
/// <devdoc>
/// Helper class for data bound controls to wrap an generic data source
/// with a strongly typed IDataSource. This class automatically handles
/// other IDataSources, IEnumerable, and IListSource objects.
/// This class uses ReadOnlyDataSourceView to represent individual views.
/// </devdoc>
internal sealed class ReadOnlyDataSource : IDataSource {
private static string[] ViewNames = new string[0];
private string _dataMember;
private object _dataSource;
public ReadOnlyDataSource(object dataSource, string dataMember) {
Debug.Assert(dataSource == null || (dataSource is IEnumerable || dataSource is IDataSource || dataSource is IListSource), "Expected dataSource to be either null, an IEnumerable, an IDataSource, or an IListSource.");
_dataSource = dataSource;
_dataMember = dataMember;
}
#region Implementation of IDataSource
event EventHandler IDataSource.DataSourceChanged {
add {
}
remove {
}
}
/// <devdoc>
/// Check for IDataSource, IListSource, and IEnumerable, and return an
/// approprite DataSourceView.
/// </devdoc>
DataSourceView IDataSource.GetView(string viewName) {
// Check first for IDataSource
IDataSource ds = _dataSource as IDataSource;
if (ds != null) {
return ds.GetView(viewName);
}
IEnumerable enumerable = DataSourceHelper.GetResolvedDataSource(_dataSource, _dataMember);
return new ReadOnlyDataSourceView(this, _dataMember, enumerable);
}
ICollection IDataSource.GetViewNames() {
return ViewNames;
}
#endregion
}
}
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