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//------------------------------------------------------------------------------
// <copyright file="ListSourceHelper.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//------------------------------------------------------------------------------
namespace System.Web.UI {
using System.Collections;
using System.ComponentModel;
public static class ListSourceHelper {
public static bool ContainsListCollection(IDataSource dataSource) {
ICollection viewNames = dataSource.GetViewNames();
if (viewNames != null && viewNames.Count > 0) {
return true;
}
return false;
}
public static IList GetList(IDataSource dataSource) {
ICollection viewNames = dataSource.GetViewNames();
if (viewNames != null && viewNames.Count > 0) {
return new ListSourceList(dataSource);
}
return null;
}
internal sealed class ListSourceList : CollectionBase, ITypedList {
IDataSource _dataSource;
public ListSourceList(IDataSource dataSource) {
_dataSource = dataSource;
((IList)this).Add(new ListSourceRow(_dataSource));
}
#region ITypedList implementation
string ITypedList.GetListName(PropertyDescriptor[] listAccessors) {
return String.Empty;
}
PropertyDescriptorCollection ITypedList.GetItemProperties(PropertyDescriptor[] listAccessors) {
if (_dataSource != null) {
ICollection viewNames = _dataSource.GetViewNames();
if (viewNames != null && viewNames.Count > 0) {
string[] viewNamesArray = new string[viewNames.Count];
viewNames.CopyTo(viewNamesArray, 0);
PropertyDescriptor[] props = new PropertyDescriptor[viewNames.Count];
for (int i = 0; i < viewNamesArray.Length; i++) {
props[i] = new ListSourcePropertyDescriptor(viewNamesArray[i]);
}
return new PropertyDescriptorCollection(props);
}
}
return new PropertyDescriptorCollection(null);
}
#endregion ITypedList implementations
}
internal class ListSourceRow {
IDataSource _dataSource;
public ListSourceRow(IDataSource dataSource) {
_dataSource = dataSource;
}
public IDataSource DataSource {
get {
return _dataSource;
}
}
}
internal class ListSourcePropertyDescriptor : PropertyDescriptor {
string _name;
public ListSourcePropertyDescriptor(string name) : base(name, null) {
_name = name;
}
public override Type ComponentType {
get {
return typeof(ListSourceRow);
}
}
public override bool IsReadOnly {
get {
return true;
}
}
public override Type PropertyType {
get {
return typeof(IEnumerable);
}
}
public override bool CanResetValue(object value) {
return false;
}
public override object GetValue(object source) {
if (source is ListSourceRow) {
ListSourceRow row = (ListSourceRow)source;
IDataSource dataSource = row.DataSource;
return dataSource.GetView(_name).ExecuteSelect(DataSourceSelectArguments.Empty);
}
return null;
}
public override void ResetValue(object component) {
throw new NotSupportedException();
}
public override void SetValue(object component, object value) {
throw new NotSupportedException();
}
public override bool ShouldSerializeValue(object component) {
return false;
}
}
}
}
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