protected virtual void SetProperty(ModelBindingExecutionContext modelBindingExecutionContext, ModelBindingContext bindingContext, ModelMetadata propertyMetadata, ComplexModelResult complexModelResult)
{
PropertyDescriptor propertyDescriptor = TypeDescriptorHelper.Get(bindingContext.ModelType).GetProperties().Find(propertyMetadata.PropertyName, true /* ignoreCase */);
if (propertyDescriptor == null || propertyDescriptor.IsReadOnly)
{
return; // nothing to do
}
object value = complexModelResult.Model ?? GetPropertyDefaultValue(propertyDescriptor);
propertyMetadata.Model = value;
// 'Required' validators need to run first so that we can provide useful error messages if
// the property setters throw, e.g. if we're setting entity keys to null. See comments in
// DefaultModelBinder.SetProperty() for more information.
if (value == null)
{
string modelStateKey = complexModelResult.ValidationNode.ModelStateKey;
if (bindingContext.ModelState.IsValidField(modelStateKey))
{
ModelValidator requiredValidator = ModelValidatorProviders.Providers.GetValidators(propertyMetadata, modelBindingExecutionContext).Where(v => v.IsRequired).FirstOrDefault();
if (requiredValidator != null)
{
foreach (ModelValidationResult validationResult in requiredValidator.Validate(bindingContext.Model))
{
bindingContext.ModelState.AddModelError(modelStateKey, validationResult.Message);
}
}
}
}
if (value != null || TypeHelpers.TypeAllowsNullValue(propertyDescriptor.PropertyType))
{
try {
propertyDescriptor.SetValue(bindingContext.Model, value);
}
catch (Exception ex) {
// don't display a duplicate error message if a binding error has already occurred for this field
string modelStateKey = complexModelResult.ValidationNode.ModelStateKey;
if (bindingContext.ModelState.IsValidField(modelStateKey))
{
bindingContext.ModelState.AddModelError(modelStateKey, ex);
}
}
}
else
{
// trying to set a non-nullable value type to null, need to make sure there's a message
string modelStateKey = complexModelResult.ValidationNode.ModelStateKey;
if (bindingContext.ModelState.IsValidField(modelStateKey))
{
complexModelResult.ValidationNode.Validated += CreateNullCheckFailedHandler(modelBindingExecutionContext, propertyMetadata, value);
}
}
}
public ModelMetadata(ModelMetadataProvider provider, Type containerType, Func <object> modelAccessor, Type modelType, string propertyName)
{
if (provider == null)
{
throw new ArgumentNullException("provider");
}
if (modelType == null)
{
throw new ArgumentNullException("modelType");
}
Provider = provider;
_containerType = containerType;
_isRequired = !TypeHelpers.TypeAllowsNullValue(modelType);
_modelAccessor = modelAccessor;
_modelType = modelType;
_propertyName = propertyName;
}
