//
// System.Web.UI.WebControls.DataBoundControl
//
// Authors:
// Ben Maurer (bmaurer@users.sourceforge.net)
// Sanjay Gupta (gsanjay@novell.com)
//
// (C) 2003 Ben Maurer
// (C) 2004 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.
//
#if NET_2_0
using System.Collections;
using System.Collections.Specialized;
using System.Text;
using System.Web.Util;
using System.ComponentModel;
using System.Security.Permissions;
using System.Web.UI.WebControls.Adapters;
namespace System.Web.UI.WebControls{
// CAS
[AspNetHostingPermission (SecurityAction.LinkDemand, Level = AspNetHostingPermissionLevel.Minimal)]
[AspNetHostingPermission (SecurityAction.InheritanceDemand, Level = AspNetHostingPermissionLevel.Minimal)]
// attributes
[DesignerAttribute ("System.Web.UI.Design.WebControls.DataBoundControlDesigner, " + Consts.AssemblySystem_Design, "System.ComponentModel.Design.IDesigner")]
public abstract class DataBoundControl : BaseDataBoundControl
{
DataSourceSelectArguments selectArguments;
DataSourceView currentView;
protected DataBoundControl ()
{
}
/* Used for controls that used to inherit from
* WebControl, so the tag can propagate upwards
*/
internal DataBoundControl (HtmlTextWriterTag tag) : base (tag)
{
}
protected virtual IDataSource GetDataSource ()
{
if (IsBoundUsingDataSourceID) {
Control ctrl = FindDataSource ();
if (ctrl == null)
throw new HttpException (string.Format ("A control with ID '{0}' could not be found.", DataSourceID));
if (!(ctrl is IDataSource))
throw new HttpException (string.Format ("The control with ID '{0}' is not a control of type IDataSource.", DataSourceID));
return (IDataSource) ctrl;
}
IDataSource ds = DataSource as IDataSource;
if (ds != null) return ds;
IEnumerable ie = DataSourceResolver.ResolveDataSource (DataSource, DataMember);
return new CollectionDataSource (ie);
}
protected virtual DataSourceView GetData ()
{
if (currentView == null)
UpdateViewData ();
return currentView;
}
DataSourceView InternalGetData ()
{
if (currentView != null)
return currentView;
if (DataSource != null && IsBoundUsingDataSourceID)
throw new HttpException ("Control bound using both DataSourceID and DataSource properties.");
IDataSource ds = GetDataSource ();
if (ds != null)
return ds.GetView (DataMember);
else
return null;
}
protected override void OnDataPropertyChanged ()
{
base.OnDataPropertyChanged ();
currentView = null;
}
protected virtual void OnDataSourceViewChanged (object sender, EventArgs e)
{
RequiresDataBinding = true;
}
// MSDN: The OnPagePreLoad method is overridden by the DataBoundControl class
// to set the BaseDataBoundControl.RequiresDataBinding property to true in
// cases where the HTTP request is a postback and view state is enabled but
// the data-bound control has not yet been bound.
//
// LAMESPEC: RequiresDataBinding is also set when http request is NOT a postback -
// no matter whether view state is enabled. The correct description should be:
//
// The OnPagePreLoad method is override by the DataBoundControl class
// to set the BaseDataBoundControl.RequiresDataBinding property to true in
// cases where the HTTP request is not a postback or it is a postback and view state
// is enabled but the data-bound control has not yet been bound.
protected override void OnPagePreLoad (object sender, EventArgs e)
{
base.OnPagePreLoad (sender, e);
Initialize ();
}
void Initialize ()
{
Page page = Page;
if (page != null && !IsDataBound) {
// LAMESPEC: see the comment above OnPagePreLoad
if (!page.IsPostBack)
RequiresDataBinding = true;
else if (IsViewStateEnabled)
RequiresDataBinding = true;
}
}
void UpdateViewData ()
{
if (currentView != null)
currentView.DataSourceViewChanged -= new EventHandler (OnDataSourceViewChanged);
DataSourceView view = InternalGetData ();
if (view != currentView)
currentView = view;
if (currentView != null)
currentView.DataSourceViewChanged += new EventHandler (OnDataSourceViewChanged);
}
protected internal override void OnLoad (EventArgs e)
{
UpdateViewData ();
if (!Initialized) {
Initialize ();
// MSDN: The ConfirmInitState method sets the initialized state of the data-bound
// control. The method is called by the DataBoundControl class in its OnLoad
// method.
ConfirmInitState ();
}
base.OnLoad(e);
}
protected internal virtual void PerformDataBinding (IEnumerable data)
{
}
protected override void ValidateDataSource (object dataSource)
{
if (dataSource == null || dataSource is IListSource || dataSource is IEnumerable || dataSource is IDataSource)
return;
throw new ArgumentException ("Invalid data source source type. The data source must be of type IListSource, IEnumerable or IDataSource.");
}
[ThemeableAttribute (false)]
[DefaultValueAttribute ("")]
[WebCategoryAttribute ("Data")]
public virtual string DataMember {
get { return ViewState.GetString ("DataMember", ""); }
set { ViewState["DataMember"] = value; }
}
[IDReferencePropertyAttribute (typeof(DataSourceControl))]
public override string DataSourceID {
get { return ViewState.GetString ("DataSourceID", ""); }
set {
ViewState ["DataSourceID"] = value;
base.DataSourceID = value;
}
}
#if NET_4_0
[Browsable (false)]
[DesignerSerializationVisibility (DesignerSerializationVisibility.Hidden)]
public
#else
internal
#endif
IDataSource DataSourceObject {
get { return GetDataSource (); }
}
//
// See DataBoundControl.MarkAsDataBound msdn doc for the code example
//
protected override void PerformSelect ()
{
// Call OnDataBinding here if bound to a data source using the
// DataSource property (instead of a DataSourceID), because the
// databinding statement is evaluated before the call to GetData.
if (!IsBoundUsingDataSourceID)
OnDataBinding (EventArgs.Empty);
// prevent recursive calls
RequiresDataBinding = false;
SelectArguments = CreateDataSourceSelectArguments ();
GetData ().Select (SelectArguments, new DataSourceViewSelectCallback (OnSelect));
// The PerformDataBinding method has completed.
MarkAsDataBound ();
// Raise the DataBound event.
OnDataBound (EventArgs.Empty);
}
void OnSelect (IEnumerable data)
{
// Call OnDataBinding only if it has not already been
// called in the PerformSelect method.
if (IsBoundUsingDataSourceID) {
OnDataBinding (EventArgs.Empty);
}
// The PerformDataBinding method binds the data in the
// retrievedData collection to elements of the data-bound control.
InternalPerformDataBinding (data);
}
#if NET_4_0
internal
#else
protected
#endif
void InternalPerformDataBinding (IEnumerable data)
{
DataBoundControlAdapter adapter = Adapter as DataBoundControlAdapter;
if (adapter != null)
adapter.PerformDataBinding (data);
else
PerformDataBinding (data);
}
protected virtual DataSourceSelectArguments CreateDataSourceSelectArguments ()
{
return DataSourceSelectArguments.Empty;
}
protected DataSourceSelectArguments SelectArguments {
get {
if (selectArguments == null)
selectArguments = CreateDataSourceSelectArguments ();
return selectArguments;
}
private set {
selectArguments = value;
}
}
bool IsDataBound {
get {
object dataBound = ViewState ["DataBound"];
return dataBound != null ? (bool) dataBound : false;
}
set {
ViewState ["DataBound"] = value;
}
}
protected void MarkAsDataBound ()
{
IsDataBound = true;
}
}
}
#endif
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