protected override bool ConditionApplies(ModelInstance root)
{
// Get the allowed values
var allowedValues = GetAllowedValues(root);
// Always consider as valid when there are no allowed values
if (allowedValues == null)
{
return(false);
}
// Value properties
if (Property is ModelValueProperty)
{
// List
if (Property.IsList)
{
// Get the current property value
var values = root.GetValue((ModelValueProperty)Property) as IEnumerable;
// Determine whether the property value is in the list of allowed values
return(!(values == null || values.Cast <object>().All(value => allowedValues.Contains(value))));
}
// Value
else
{
// Get the current property value
var value = root.GetValue((ModelValueProperty)Property);
// Determine whether the property value is in the list of allowed values
return(!(value == null || allowedValues.Contains(value)));
}
}
// Reference properties
else
{
// List Property
if (Property.IsList)
{
// Get the current property value
ModelInstanceList values = root.GetList((ModelReferenceProperty)Property);
// Determine whether the property value is in the list of allowed values
return(!(values == null || values.All(value => allowedValues.Contains(value))));
}
// Reference Property
else
{
// Get the current property value
ModelInstance value = root.GetReference((ModelReferenceProperty)Property);
// Determine whether the property value is in the list of allowed values
return(!(value == null || allowedValues.Contains(value)));
}
}
}
protected override ValidationResult IsValid(object value, ValidationContext validationContext)
{
var instance = ModelInstance.GetModelInstance(validationContext.ObjectInstance);
var source = new ModelSource(instance.Type, Source);
// Get the member name by looking up using the display name, since the member name is mysteriously null for MVC3 projects
var propertyName = validationContext.MemberName ?? validationContext.ObjectType.GetProperties()
.Where(p => p.GetCustomAttributes(false).OfType <DisplayAttribute>()
.Any(a => a.Name == validationContext.DisplayName)).Select(p => p.Name).FirstOrDefault();
var property = instance.Type.Properties[propertyName];
// Get the list of allowed values
ModelInstanceList allowedValues = source.GetList(instance);
if (allowedValues == null)
{
return(null);
}
// List Property
if (property.IsList)
{
// Get the current property value
ModelInstanceList items = instance.GetList((ModelReferenceProperty)property);
// Determine whether the property value is in the list of allowed values
if (!(items == null || items.All(item => allowedValues.Contains(item))))
{
return(new ValidationResult("Invalid value", new string[] { propertyName }));
}
}
// Reference Property
else
{
// Get the current property value
ModelInstance item = instance.GetReference((ModelReferenceProperty)property);
// Determine whether the property value is in the list of allowed values
if (!(item == null || allowedValues.Contains(item)))
{
return(new ValidationResult("Invalid value", new string[] { propertyName }));
}
}
return(null);
}
/// <summary>
/// Ensure the destination instance path is valid when nulls are encountered along the path.
/// </summary>
/// <param name="instance"></param>
/// <param name="property"></param>
/// <param name="index"></param>
bool EnsureDestinationInstance(ModelInstance instance, ModelReferenceProperty property, int index)
{
if (property.IsList)
{
ModelInstanceList list = instance.GetList(property);
for (int i = list.Count; i <= index; i++)
{
list.Add(property.PropertyType.Create());
}
}
else
{
instance.SetReference(property, property.PropertyType.Create());
}
return(true);
}
