/// <summary>
/// Creates a new instance of this class.
/// </summary>
/// <param name="result">The comparison's computed result.</param>
/// <param name="property1">Property information for the property in the first object.</param>
/// <param name="value1">Value found in the property of the first object.</param>
/// <param name="property2">Property information for the property in the second object.</param>
/// <param name="value2">Value found in the property of the second object.</param>
/// <param name="mappingUsed">Mapping information used during the comparison operation.</param>
/// <param name="exception">Exception raised during the comparison operation, if any.</param>
internal PropertyComparisonResult(ComparisonResult result, PropertyComparisonInfo property1, object value1,
PropertyComparisonInfo property2 = null, object value2 = null, PropertyMap mappingUsed = null,
System.Exception exception = null)
{
Result = result;
Property1 = property1;
Property2 = property2;
Value1 = value1;
Value2 = value2;
MapUsed = mappingUsed;
Exception = exception;
}
/// <summary>
/// Configures the property comparison information of the source property to ignore the
/// specified property during the comparison routine against objects of type
/// <see cref="TDestination"/>.
/// </summary>
/// <typeparam name="TSourceProperty">The type of the source property.</typeparam>
/// <param name="sourcePropExpr">Source property lambda expression.</param>
/// <returns>This configuration object to enable fluent syntax.</returns>
public ComparerConfiguration <TSource, TDestination> IgnoreProperty <TSourceProperty>(
Expression <Func <TSource, TSourceProperty> > sourcePropExpr
)
{
PropertyInfo piSource = ExpressionHelper.GetPropertyInfo(sourcePropExpr, nameof(sourcePropExpr));
PropertyComparisonInfo pci = TypeInfo1.Properties[piSource.Name];
//Ignore only for the specified data type.
PropertyMap map = new PropertyMap(
Type2,
PropertyMapOperation.IgnoreProperty
);
pci.Maps.Replace(map);
return(this);
}
/// <summary>
/// Creates a copy of this object.
/// </summary>
/// <param name="clonePropertyMaps">A Boolean value that indicates if property maps should
/// be cloned as well.</param>
/// <returns>A type information object that contains the same information as this object.</returns>
internal TypeInfo Clone(bool clonePropertyMaps)
{
TypeInfo ti = new TypeInfo(DataType, PropertyMapsIgnored);
foreach (PropertyComparisonInfo pci in Properties)
{
PropertyComparisonInfo newPci = new PropertyComparisonInfo(pci.PropertyDescriptor, pci.IgnoreProperty);
if (!PropertyMapsIgnored && pci.Maps.Count > 0 && clonePropertyMaps)
{
foreach (PropertyMap pm in pci.Maps)
{
newPci.Maps.Add(pm);
}
}
ti.Properties.Add(newPci);
}
return(ti);
}
/// <summary>
/// Creates and returns a list of <see cref="PropertyComparisonInfo"/> objects from a list of
/// <see cref="PropertyDescriptor"/> objects.
/// </summary>
/// <param name="pdColl">The collection of property descriptors.</param>
/// <param name="ignorePropertyMappings">A Boolean value that indicates if property
/// mappings defined through attributes should be ignored.</param>
/// <returns>An enumeration that lists the created <see cref="PropertyComparisonInfo"/> objects.</returns>
private static IEnumerable <PropertyComparisonInfo> ObtainPropertyInfos(PropertyDescriptorCollection pdColl, bool ignorePropertyMappings)
{
foreach (PropertyDescriptor pd in pdColl)
{
IgnoreForComparisonAttribute ignoreAtt = pd.Attributes.OfType <IgnoreForComparisonAttribute>().FirstOrDefault();
PropertyComparisonInfo pci = new PropertyComparisonInfo(pd, ignoreAtt?.IgnoreOptions ?? IgnorePropertyOptions.DoNotIgnore);
if (!ignorePropertyMappings)
{
//Obtain maps.
foreach (PropertyMapAttribute attribute in pd.Attributes.OfType <PropertyMapAttribute>())
{
if (attribute == null)
{
continue;
}
pci.Maps.Add(attribute.PropertyMap);
}
}
yield return(pci);
}
}
/// <summary>
/// Creates a <see cref="TypeInfo"/> object with the necessary property information to
/// compare objects of the specified type.
/// </summary>
/// <param name="type">The data type whose type information is requested.</param>
/// <param name="ignorePropertyMappings">A Boolean value that indicates if property
/// mappings defined through attributes should be ignored. If the argument is not
/// provided, then by default the property mappings are included.</param>
/// <returns>A <see cref="TypeInfo"/> object that can be used to compare properties.</returns>
internal static TypeInfo BuildTypeInformation(Type type, bool ignorePropertyMappings = false)
{
TypeInfo ti = new TypeInfo(type, ignorePropertyMappings);
#if NET461
//Obtain property map and ignore property data from MetadataTypeAttribute, if present.
PropertyComparisonInfoCollection metadataOnlyPropertyInfos = new PropertyComparisonInfoCollection();
MetadataTypeAttribute att = type.GetCustomAttribute <MetadataTypeAttribute>();
if (att != null)
{
foreach (PropertyComparisonInfo pi in ObtainPropertyInfos(TypeDescriptor.GetProperties(att.MetadataClassType), ignorePropertyMappings))
{
metadataOnlyPropertyInfos.Add(pi);
}
}
#endif
//Now process regular property descriptors.
foreach (PropertyComparisonInfo pci in ObtainPropertyInfos(TypeDescriptor.GetProperties(type), ignorePropertyMappings))
{
#if NET461
if (!ignorePropertyMappings && metadataOnlyPropertyInfos.Contains(pci.Name))
{
PropertyComparisonInfo mpci = metadataOnlyPropertyInfos[pci.Name];
//Combine the IgnoreProperty values.
pci.IgnoreProperty |= mpci.IgnoreProperty;
//Merge the PropertyMap objects.
foreach (PropertyMap pm in mpci.Maps)
{
if (pci.Maps.Contains(pm.TargetType))
{
continue;
}
pci.Maps.Add(pm);
}
}
#endif
ti.Properties.Add(pci);
}
return(ti);
}
/// <summary>
/// Compares the property values of the first object against the property values of the
/// second object according to the preset property mapping rules between the two object
/// data types.
/// </summary>
/// <param name="object1">The first object to be compared against a second object.</param>
/// <param name="object2">The second object of the comparison operation.</param>
/// <param name="results">If provided, it will be used to collect the comparison results.</param>
/// <returns>A Boolean value with the summarized result of the comparison. True if any
/// property values were deemed different; false if all property values turned out equal.</returns>
/// <exception cref="ArgumentNullException">Thrown if either object is null.</exception>
/// <exception cref="ArgumentException">Thrown if either object is not of the expected
/// data type.</exception>
/// <exception cref="InvalidOperationException">Thrown if both objects are really the same
/// object.</exception>
public bool Compare(object object1, object object2, ICollection <PropertyComparisonResult> results = null)
{
#region Argument Validation
Guard.RequiredArgument(object1, nameof(object1));
Guard.RequiredArgument(object2, nameof(object2));
Guard.ArgumentCondition(
() => object1.GetType() == Type1, nameof(object1),
$"The provided object is not of the expected type ({Type1})."
);
Guard.ArgumentCondition(
() => object2.GetType() == Type2, nameof(object2),
$"The provided object is not of the expected type ({Type2})."
);
Guard.Condition(() => !Object.ReferenceEquals(object1, object2), "The objects to compare must be different.");
#endregion
bool isDifferent = false;
foreach (PropertyComparisonInfo pci1 in _typeInfo1.Properties)
{
ComparisonResult result = ComparisonResult.Undefined;
//Obtain the PropertyMapping for this propertyInfo.
//If none, map by property name.
PropertyMap mapToUse = null;
if (pci1.Maps.Contains(Type2))
{
mapToUse = pci1.Maps[Type2];
}
object val1 = null;
object val2 = null;
PropertyComparisonInfo pci2 = null;
System.Exception catchedException = null;
//Ignore the property if no mapping exists and is being ignored for type 2,
//or mapping exists and it states the property must be ignored.
bool propertyIgnored =
((pci1.IgnoreProperty & IgnorePropertyOptions.IgnoreForSelf) == IgnorePropertyOptions.IgnoreForSelf && Type1 == Type2) ||
((pci1.IgnoreProperty & IgnorePropertyOptions.IgnoreForOthers) == IgnorePropertyOptions.IgnoreForOthers && Type1 != Type2);
if ((mapToUse == null && propertyIgnored) ||
(mapToUse?.Operation == PropertyMapOperation.IgnoreProperty))
{
result |= ComparisonResult.PropertyIgnored;
}
else
{
string prop2Name = mapToUse?.TargetProperty ?? pci1.Name;
//Get the property value of the first object.
val1 = pci1.GetValue(object1);
if (_typeInfo2.Properties.Contains(prop2Name))
{
//Get the property value of the second object.
pci2 = _typeInfo2.Properties[prop2Name];
val2 = pci2.GetValue(object2);
//Determine any base type to cover for T? vs T or vice versa.
Type p1BaseType = GetNullableUnderlyingType(pci1.PropertyType) ?? pci1.PropertyType;
Type p2BaseType = GetNullableUnderlyingType(pci2.PropertyType) ?? pci2.PropertyType;
//Determine the comparer to use.
IComparer comparer = null;
if ((mapToUse?.ForceStringValue ?? false) ||
p1BaseType != p2BaseType)
{
comparer = ResolveComparerForType(typeof(string));
try
{
val1 = ConvertPropertyValueToString(val1, mapToUse?.FormatString);
val2 = ConvertPropertyValueToString(val2, mapToUse?.TargetFormatString);
}
catch (System.Exception ex)
{
result |= ComparisonResult.StringCoercionException;
catchedException = ex;
}
result |= ComparisonResult.StringCoercion;
}
else
{
comparer = ResolveComparerForType(p1BaseType);
}
if (catchedException == null)
{
try
{
int comp = comparer.Compare(val1, val2);
if (comp < 0)
{
result |= ComparisonResult.LessThan;
}
else if (comp > 0)
{
result |= ComparisonResult.GreaterThan;
}
else
{
result |= ComparisonResult.Equal;
}
}
catch (System.ArgumentException)
{
//Property type does not implement IComparable and there is no comparer
//registered for the data type.
result |= ComparisonResult.NoComparer;
//So try to at least find out if it is equal or not.
try
{
if (Object.Equals(val1, val2))
{
result |= ComparisonResult.Equal;
}
else
{
result |= ComparisonResult.NotEqual;
}
}
catch (System.Exception ex)
{
result |= ComparisonResult.ComparisonException;
catchedException = ex;
}
}
catch (System.Exception ex)
{
result |= ComparisonResult.ComparisonException;
catchedException = ex;
}
}
}
else
{
//We are done here since there is no matching property to compare against.
result |= ComparisonResult.PropertyNotFound;
}
}
PropertyComparisonResult pcr = new PropertyComparisonResult(result, pci1, val1, pci2,
val2, mapToUse, catchedException);
results?.Add(pcr);
isDifferent = isDifferent || ((result & ComparisonResult.NotEqual) ==
ComparisonResult.NotEqual);
}
return(isDifferent);
}
