/// <inheritdoc />
public Task BindModelAsync(ModelBindingContext bindingContext)
{
if (bindingContext == null)
{
throw new ArgumentNullException(nameof(bindingContext));
}
ModelBindingHelper.ValidateBindingContext(bindingContext);
if (!CanBindType(bindingContext.ModelMetadata))
{
return(TaskCache.CompletedTask);
}
if (!CanCreateModel(bindingContext))
{
return(TaskCache.CompletedTask);
}
// Perf: separated to avoid allocating a state machine when we don't
// need to go async.
return(BindModelCoreAsync(bindingContext));
}
/// <inheritdoc />
public virtual async Task BindModelAsync(ModelBindingContext bindingContext)
{
if (bindingContext == null)
{
throw new ArgumentNullException(nameof(bindingContext));
}
ModelBindingHelper.ValidateBindingContext(bindingContext);
var model = bindingContext.Model;
if (!bindingContext.ValueProvider.ContainsPrefix(bindingContext.ModelName))
{
// If we failed to find data for a top-level model, then generate a
// default 'empty' model (or use existing Model) and return it.
if (bindingContext.IsTopLevelObject)
{
if (model == null)
{
model = CreateEmptyCollection(bindingContext.ModelType);
}
bindingContext.Result = ModelBindingResult.Success(bindingContext.ModelName, model);
}
return;
}
var valueProviderResult = bindingContext.ValueProvider.GetValue(bindingContext.ModelName);
CollectionResult result;
if (valueProviderResult == ValueProviderResult.None)
{
result = await BindComplexCollection(bindingContext);
}
else
{
result = await BindSimpleCollection(bindingContext, valueProviderResult);
}
var boundCollection = result.Model;
if (model == null)
{
model = ConvertToCollectionType(bindingContext.ModelType, boundCollection);
}
else
{
// Special case for TryUpdateModelAsync(collection, ...) scenarios. Model is null in all other cases.
CopyToModel(model, boundCollection);
}
Debug.Assert(model != null);
if (result.ValidationStrategy != null)
{
bindingContext.ValidationState.Add(model, new ValidationStateEntry()
{
Strategy = result.ValidationStrategy,
});
}
if (valueProviderResult != ValueProviderResult.None)
{
// If we did simple binding, then modelstate should be updated to reflect what we bound for ModelName.
// If we did complex binding, there will already be an entry for each index.
bindingContext.ModelState.SetModelValue(
bindingContext.ModelName,
valueProviderResult);
}
bindingContext.Result = ModelBindingResult.Success(bindingContext.ModelName, model);
}
