[DesignerAttribute ("System.Web.UI.Design.WebControls.BaseDataBoundControlDesigner, " + Consts.AssemblySystem_Design, "System.ComponentModel.Design.IDesigner")]
public abstract class BaseDataBoundControl: WebControl
{
- public event EventHandler DataBound;
+ static readonly object dataBoundEvent = new object ();
+
+ EventHandlerList events = new EventHandlerList ();
+
+ public event EventHandler DataBound {
+ add { events.AddHandler (dataBoundEvent, value); }
+ remove { events.RemoveHandler (dataBoundEvent, value); }
+ }
object dataSource;
bool initialized;
+ bool preRendered;
bool requiresDataBinding;
protected BaseDataBoundControl ()
return dataSource;
}
set {
- ValidateDataSource (value);
+ if(value!=null)
+ ValidateDataSource (value);
dataSource = value;
- if (initialized)
- OnDataPropertyChanged ();
+ OnDataPropertyChanged ();
}
}
}
set {
ViewState["DataSourceID"] = value;
- if (initialized)
- OnDataPropertyChanged ();
+ OnDataPropertyChanged ();
}
}
protected bool RequiresDataBinding {
get { return requiresDataBinding; }
- set { requiresDataBinding = value; }
+ set {
+ // MSDN: If you set the RequiresDataBinding
+ // property to true when the data-bound control
+ // has already begun to render its output to the
+ // page, the current HTTP request is not a
+ // callback, and you are using the DataSourceID
+ // property to identify the data source control
+ // to bind to, the DataBind method is called
+ // immediately. In this case, the
+ // RequiresDataBinding property is _not_ actually
+ // set to true.
+ //
+ // LAMESPEC, the docs quoted above mention that
+ // DataBind is called in the described
+ // case. This is wrong since that way we don't
+ // break recursion when the property is set from
+ // within the OnSelect handler in user's
+ // code. EnsureDataBound makes sure that no
+ // recursive binding is performed. Also the
+ // property DOES get set in this case (according
+ // to tests)
+ if (value && preRendered && IsBoundUsingDataSourceID && Page != null && !Page.IsCallback) {
+ requiresDataBinding = true;
+ EnsureDataBound ();
+ } else
+ requiresDataBinding = value;
+ }
}
protected void ConfirmInitState ()
public override void DataBind ()
{
- RequiresDataBinding = false;
PerformSelect ();
}
protected virtual void OnDataBound (EventArgs e)
{
- if (DataBound != null)
- DataBound (this, e);
+ EventHandler eh = events [dataBoundEvent] as EventHandler;
+ if (eh != null)
+ eh (this, e);
}
protected virtual void OnDataPropertyChanged ()
{
- RequiresDataBinding = true;
+ if (Initialized)
+ RequiresDataBinding = true;
}
protected internal override void OnInit (EventArgs e)
{
base.OnInit (e);
Page.PreLoad += new EventHandler (OnPagePreLoad);
+
+ if (!IsViewStateEnabled && Page != null && Page.IsPostBack)
+ RequiresDataBinding = true;
}
protected virtual void OnPagePreLoad (object sender, EventArgs e)
protected internal override void OnPreRender (EventArgs e)
{
+ preRendered = true;
EnsureDataBound ();
base.OnPreRender (e);
}
+
+ internal Control FindDataSource ()
+ {
+ Control ctrl = null;
+ Control namingContainer = NamingContainer;
+
+ while (namingContainer != null) {
+ ctrl = namingContainer.FindControl (DataSourceID);
+ if (ctrl != null)
+ break;
+ namingContainer = namingContainer.NamingContainer;
+ }
+
+ return ctrl;
+ }
protected abstract void PerformSelect ();
#endif
+