public TValue GetValue(IBehaviorContext context)
{
RequireInitialized();
if (!_cache.HasValue(context))
{
if (_isProviding.GetWithDefault(context, false))
{
// This check is important to avoid the following endless recursion:
// 1. GetValue calls ProvideValue
// 2. ProvideValue directly or indirectly calls GetValue
// 3. GetValue calls Provide value because the cache is not set yet.
// 4. ProvideValue calls GetValue again
//
// The alternative would be to return default(TValue) but it is better
// to avoid this situation altogehter.
throw new InvalidOperationException(EViewModels.ValueAccessedWithinProvideValue);
}
_isProviding.Set(context, true);
TValue value = ProvideValue(context);
_cache.Set(context, value);
_isProviding.Clear(context);
OnInitialize(context);
}
return(_cache.Get(context));
}
private IEnumerable <TItemSource> GetSourceItems(IBehaviorContext context)
{
if (!_shouldCacheSourceCollection)
{
IEnumerable <TItemSource> source = this.GetValueNext <IEnumerable <TItemSource> >(context);
return(source);
}
if (!_collectionSourceCache.HasValue(context))
{
IEnumerable <TItemSource> source = this.GetValueNext <IEnumerable <TItemSource> >(context);
_collectionSourceCache.Set(context, source);
}
return(_collectionSourceCache.Get(context));
}
public void BeginValidation(IBehaviorContext context, ValidationController controller)
{
_validationController.Set(context, controller);
this.BeginValidationNext(context, controller);
}
private void CachePotentiallyInvalidValue(IBehaviorContext context, TValue value)
{
_invalidValueCache.Set(context, value);
}
