/// <summary>
/// Basic constructor.
/// </summary>
/// <param name="reader">Instance of an <see cref="T:System.Data.Common.DbDataReader"/> object.</param>
public DataReaderService(DbDataReader reader)
{
if (reader == null)
{
throw new ArgumentNullException("reader", "Unable to create DataReaderService for an empty reader.");
}
this._reader = reader;
this._hasRows = this._reader.HasRows;
this._fieldCount = this._reader.FieldCount;
this._isClosed = false;
this._columns = null;
this._metaInfo = null;
this._result = new List <T>();
}
/// <summary>
/// Gets meta info for the entity.
/// </summary>
/// <returns>Returns instance of an <see cref="xDev.Data.DataReaderService{T}"/>.</returns>
public DataReaderService <T> GetMetaInfo()
{
if (this._metaInfo != null)
{
return(this);
}
CheckIsClosed();
// Get meta info for the entity type
this._metaInfo = MetaInfo <T> .GetMetaInfo();
return(this);
}
/// <summary>
/// Gets the meta information for the entity.
/// </summary>
/// <typeparam name="T">Type of the entity.</typeparam>
/// <param name="this">Instance of an entity.</param>
/// <returns>Returns new instance of a <see cref="xDev.Data.MetaInfo{T}"/> class.</returns>
public static MetaInfo <T> GetMetaInfo <T>(this IEntity <T> @this)
where T : class, IEntity <T>, new()
{
var entityType = typeof(T);
MetaInfo <T> info = null;
lock (IEntityExtensions.SyncRoot)
{
// Get WeakReference for the enityt type meta info
var infoRef = IEntityExtensions.MetaInfos.ContainsKey(entityType) ? IEntityExtensions.MetaInfos[entityType] : null;
if ((infoRef != null) && infoRef.IsAlive)
{
info = infoRef.Target as MetaInfo <T>;
}
else
{
// If there is not meta info for the desired type clear all dead references
var infoRefKeys = IEntityExtensions.MetaInfos
.Where(miRef => (miRef.Value == null) || !miRef.Value.IsAlive)
.Select(miRef => miRef.Key);
// Remove all dead referencies
foreach (var key in infoRefKeys)
{
IEntityExtensions.MetaInfos.Remove(key);
}
}
// If there is not any meta info create new one
if (info == null)
{
info = new MetaInfo <T>();
IEntityExtensions.MetaInfos[entityType] = new WeakReference(info);
}
}
return(info);
}
/// <summary>
/// Gets list of <see cref="T:System.ComponentModel.DataAnnotations.ValidationResult"/> objects
/// which represent validation state of the entity. Gets only the first invalid rule for each property.
/// </summary>
/// <typeparam name="T">Type of the entity.</typeparam>
/// <param name="entity">Instance of an entity.</param>
/// <param name="metaInfo">Entity meta info.</param>
/// <returns>Returns list of <see cref="T:System.ComponentModel.DataAnnotations.ValidationResult"/> objects.</returns>
private static IEnumerable <ValidationResult> ValidateInternal <T>(IEntity <T> entity, MetaInfo <T> metaInfo)
where T : class, IEntity <T>, new()
{
// Validate all properties
foreach (var propertyValidationRules in metaInfo.ValidationRules)
{
// Create ValidationContext
var context = new ValidationContext(entity)
{
DisplayName = propertyValidationRules.Key,
MemberName = propertyValidationRules.Key
};
// Get property value which has to be validate
var value = GetValueInternal(entity, propertyValidationRules.Key, metaInfo);
// Find invalid rule for the current property
foreach (var rule in propertyValidationRules.Value)
{
// Get the ValidationResult
var result = rule.GetValidationResult(value, context);
// If the validation result is not null than this property is invalid
if (result != null)
{
yield return(result);
}
}
}
}
/// <summary>
/// Gets value of the property.
/// </summary>
/// <typeparam name="T">Type of the entity.</typeparam>
/// <param name="entity">Instance of an entity.</param>
/// <param name="metaInfo">Entity meta info.</param>
/// <returns>Returns list of <see cref="T:System.ComponentModel.DataAnnotations.ValidationResult"/> objects.</returns>
private static object GetValueInternal <T>(IEntity <T> entity, string propertyName, MetaInfo <T> metaInfo)
where T : class, IEntity <T>, new()
{
// Check if the property name is valid
if (!metaInfo.Properties.Contains(propertyName))
{
throw new ArgumentException(string.Format(@"Unable to dynamicly get value for the property {0}. Property does not exist on the object instance.", propertyName), "propertyName");
}
// Check if there is getter for the property
if (!metaInfo.Getters.ContainsKey(propertyName))
{
throw new ArgumentException(string.Format(@"Unable to dynamicly get value for the property {0}. There is not any getter for the property.", propertyName), "propertyName");
}
try
{
// Try to get property value
return(metaInfo.Getters[propertyName].DynamicInvoke(entity));
}
catch (Exception ex)
{
throw new InvalidOperationException(string.Format(@"Unable to dynamicly get value for the property {0}.", propertyName), ex);
}
}
