/// <include file='doc\GlobalDataBindingHandler.uex' path='docs/doc[@for="GlobalDataBindingHandler.OnDataBind"]/*' />
/// <devdoc>
/// </devdoc>
public static void OnDataBind(object sender, EventArgs e)
{
Debug.Assert(sender is Control, "DataBindings can only be present on Controls.");
Control control = (Control)sender;
// check if this control has any data-bindings
IDataBindingsAccessor dataBindingsAccessor = (IDataBindingsAccessor)sender;
if (dataBindingsAccessor.HasDataBindings == false)
{
return;
}
// check if the control type has an associated data-binding handler
DataBindingHandlerAttribute handlerAttribute =
(DataBindingHandlerAttribute)TypeDescriptor.GetAttributes(sender)[typeof(DataBindingHandlerAttribute)];
if ((handlerAttribute == null) || (handlerAttribute.HandlerTypeName.Length == 0))
{
return;
}
// components in the designer/container do not get handled here; the
// designer for that control handles it in its own special way
ISite site = control.Site;
IDesignerHost designerHost = null;
if (site == null)
{
Page page = control.Page;
if (page != null)
{
site = page.Site;
}
else
{
// When the designer is working on a UserControl instead of a Page
Control parent = control.Parent;
// We shouldn't have to walk up the parent chain a whole lot - maybe a couple
// of levels on the average
while ((site == null) && (parent != null))
{
if (parent.Site != null)
{
site = parent.Site;
}
parent = parent.Parent;
}
}
}
if (site != null)
{
designerHost = (IDesignerHost)site.GetService(typeof(IDesignerHost));
}
if (designerHost == null)
{
Debug.Fail("Did not get back an IDesignerHost");
return;
}
// non-top level components, such as controls within templates do not have designers
// these are the only things that need the data-binding handler stuff
IDesigner designer = designerHost.GetDesigner(control);
if (designer != null)
{
return;
}
// get the handler and cache it the first time around
DataBindingHandler dataBindingHandler = null;
try {
string handlerTypeName = handlerAttribute.HandlerTypeName;
dataBindingHandler = (DataBindingHandler)DataBindingHandlerTable[handlerTypeName];
if (dataBindingHandler == null)
{
Type handlerType = Type.GetType(handlerTypeName);
if (handlerType != null)
{
dataBindingHandler = (DataBindingHandler)Activator.CreateInstance(handlerType, BindingFlags.Instance | BindingFlags.Public | BindingFlags.CreateInstance, null, null, null);
DataBindingHandlerTable[handlerTypeName] = dataBindingHandler;
}
}
}
catch (Exception ex) {
Debug.Fail(ex.ToString());
return;
}
// finally delegate to it to handle this particular control
if (dataBindingHandler != null)
{
dataBindingHandler.DataBindControl(designerHost, control);
}
}
public static void OnDataBind(object sender, EventArgs e)
{
Control component = (Control)sender;
IDataBindingsAccessor accessor = (IDataBindingsAccessor)sender;
if (accessor.HasDataBindings)
{
DataBindingHandlerAttribute attribute = (DataBindingHandlerAttribute)TypeDescriptor.GetAttributes(sender)[typeof(DataBindingHandlerAttribute)];
if ((attribute != null) && (attribute.HandlerTypeName.Length != 0))
{
ISite site = component.Site;
IDesignerHost designerHost = null;
if (site == null)
{
Page page = component.Page;
if (page != null)
{
site = page.Site;
}
else
{
for (Control control2 = component.Parent; (site == null) && (control2 != null); control2 = control2.Parent)
{
if (control2.Site != null)
{
site = control2.Site;
}
}
}
}
if (site != null)
{
designerHost = (IDesignerHost)site.GetService(typeof(IDesignerHost));
}
if ((designerHost != null) && (designerHost.GetDesigner(component) == null))
{
DataBindingHandler handler = null;
try
{
string handlerTypeName = attribute.HandlerTypeName;
handler = (DataBindingHandler)DataBindingHandlerTable[handlerTypeName];
if (handler == null)
{
Type type = Type.GetType(handlerTypeName);
if (type != null)
{
handler = (DataBindingHandler)Activator.CreateInstance(type, BindingFlags.CreateInstance | BindingFlags.Public | BindingFlags.Instance, null, null, null);
DataBindingHandlerTable[handlerTypeName] = handler;
}
}
}
catch (Exception)
{
return;
}
if (handler != null)
{
handler.DataBindControl(designerHost, component);
}
}
}
}
}