/// <summary>
/// 注册类型元数据描述类
/// 常用于使用 System.ComponentModel.DataAnnotations.Validator 进行数据验证时批量注入 MetadataTypes
/// </summary>
public static void Register(Assembly assembly)
{
foreach (Type type in assembly.GetTypes())
{
AttributeCollection collection = TypeDescriptor.GetAttributes(type);
foreach (var attr in collection)
{
MetadataTypeAttribute m = attr as MetadataTypeAttribute;
if (m != null)
{
TypeDescriptor.AddProviderTransparent(
new AssociatedMetadataTypeTypeDescriptionProvider(type, m.MetadataClassType), type);
}
}
}
}
/// <summary>
/// 通过使用验证上下文、验证结果集合和用于指定是否验证所有属性的值，确定指定的对象是否有效。
/// </summary>
/// <param name="instance">要验证的对象</param>
/// <param name="validationContext">用于描述要验证的对象的上下文</param>
/// <param name="validationResults">用于包含每个失败的验证的集合</param>
/// <param name="breakOnFirstError">当第一个错误产生时，是否不再进行后续验证</param>
/// <returns></returns>
public static bool TryValidateObject(object instance, ValidationContext validationContext, ICollection <ValidationResult> validationResults, bool breakOnFirstError)//, Type metadataType = null)
{
if (instance == null)
{
throw new ArgumentNullException("instance");
}
if (validationContext == null)
{
throw new ArgumentNullException("validationContext");
}
// 取当前实例的所有属性值
IDictionary <ValidationContext, object> propertyValues = XFrameworkValidator.GetPropertyValues(instance, validationContext);
List <XFrameworkValidator.ValidationError> list = new List <XFrameworkValidator.ValidationError>();
// 取元数据描述
Type metadataType = null;
//if (metadataType == null)
//{
Type type = instance.GetType();
MetadataTypeAttribute attr =
TypeDescriptor
.GetAttributes(type)
.OfType <MetadataTypeAttribute>()
.FirstOrDefault();
if (attr != null)
{
metadataType = attr.MetadataClassType;
}
//}
if (metadataType == null)
{
throw new NullReferenceException(string.Format("type {{{0}}} has no metadata descriptor.", type.Name));
}
PropertyDescriptorCollection descriptors = TypeDescriptor.GetProperties(metadataType);
// 按照元数据属性的书写顺序逐个验证实体属性
foreach (PropertyDescriptor des in descriptors)
{
KeyValuePair <ValidationContext, object> kv = propertyValues.FirstOrDefault(x => x.Key.MemberName == des.Name);
ValidationContext context = kv.Key;
object value = kv.Value;
if (context != null)
{
IEnumerable <ValidationAttribute> validationAttributes = XFrameworkValidator._store.GetPropertyValidationAttributes(context);
list.AddRange(XFrameworkValidator.GetValidationErrors(value, context, validationAttributes, breakOnFirstError));
}
if (list.Count > 0 && breakOnFirstError)
{
break;
}
}
bool result = true;
foreach (var current in list)
{
result = false;
if (validationResults != null)
{
validationResults.Add(current.ValidationResult);
}
}
return(result);
}