моє рішення, натхнене відповіддю Араса Аленіна вище, де я додав один рівень порівняння об'єктів та спеціальний об’єкт для результатів порівняння. Мені також цікаво отримати ім'я власності з ім'ям об'єкта:
public static IEnumerable<ObjectPropertyChanged> GetPublicSimplePropertiesChanged<T>(this T previous, T proposedChange,
string[] namesOfPropertiesToBeIgnored) where T : class
{
return GetPublicGenericPropertiesChanged(previous, proposedChange, namesOfPropertiesToBeIgnored, true, null, null);
}
public static IReadOnlyList<ObjectPropertyChanged> GetPublicGenericPropertiesChanged<T>(this T previous, T proposedChange,
string[] namesOfPropertiesToBeIgnored) where T : class
{
return GetPublicGenericPropertiesChanged(previous, proposedChange, namesOfPropertiesToBeIgnored, false, null, null);
}
/// <summary>
/// Gets the names of the public properties which values differs between first and second objects.
/// Considers 'simple' properties AND for complex properties without index, get the simple properties of the children objects.
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="previous">The previous object.</param>
/// <param name="proposedChange">The second object which should be the new one.</param>
/// <param name="namesOfPropertiesToBeIgnored">The names of the properties to be ignored.</param>
/// <param name="simpleTypeOnly">if set to <c>true</c> consider simple types only.</param>
/// <param name="parentTypeString">The parent type string. Meant only for recursive call with simpleTypeOnly set to <c>true</c>.</param>
/// <param name="secondType">when calling recursively, the current type of T must be clearly defined here, as T will be more generic (using base class).</param>
/// <returns>
/// the names of the properties
/// </returns>
private static IReadOnlyList<ObjectPropertyChanged> GetPublicGenericPropertiesChanged<T>(this T previous, T proposedChange,
string[] namesOfPropertiesToBeIgnored, bool simpleTypeOnly, string parentTypeString, Type secondType) where T : class
{
List<ObjectPropertyChanged> propertiesChanged = new List<ObjectPropertyChanged>();
if (previous != null && proposedChange != null)
{
var type = secondType == null ? typeof(T) : secondType;
string typeStr = parentTypeString + type.Name + ".";
var ignoreList = namesOfPropertiesToBeIgnored.CreateList();
IEnumerable<IEnumerable<ObjectPropertyChanged>> genericPropertiesChanged =
from pi in type.GetProperties(BindingFlags.Public | BindingFlags.Instance)
where !ignoreList.Contains(pi.Name) && pi.GetIndexParameters().Length == 0
&& (!simpleTypeOnly || simpleTypeOnly && pi.PropertyType.IsSimpleType())
let firstValue = type.GetProperty(pi.Name).GetValue(previous, null)
let secondValue = type.GetProperty(pi.Name).GetValue(proposedChange, null)
where firstValue != secondValue && (firstValue == null || !firstValue.Equals(secondValue))
let subPropertiesChanged = simpleTypeOnly || pi.PropertyType.IsSimpleType()
? null
: GetPublicGenericPropertiesChanged(firstValue, secondValue, namesOfPropertiesToBeIgnored, true, typeStr, pi.PropertyType)
let objectPropertiesChanged = subPropertiesChanged != null && subPropertiesChanged.Count() > 0
? subPropertiesChanged
: (new ObjectPropertyChanged(proposedChange.ToString(), typeStr + pi.Name, firstValue.ToStringOrNull(), secondValue.ToStringOrNull())).CreateList()
select objectPropertiesChanged;
if (genericPropertiesChanged != null)
{ // get items from sub lists
genericPropertiesChanged.ForEach(a => propertiesChanged.AddRange(a));
}
}
return propertiesChanged;
}
Використання наступного класу для зберігання результатів порівняння
[System.Serializable]
public class ObjectPropertyChanged
{
public ObjectPropertyChanged(string objectId, string propertyName, string previousValue, string changedValue)
{
ObjectId = objectId;
PropertyName = propertyName;
PreviousValue = previousValue;
ProposedChangedValue = changedValue;
}
public string ObjectId { get; set; }
public string PropertyName { get; set; }
public string PreviousValue { get; set; }
public string ProposedChangedValue { get; set; }
}
І вибірковий тест:
[TestMethod()]
public void GetPublicGenericPropertiesChangedTest1()
{
// Define objects to test
Function func1 = new Function { Id = 1, Description = "func1" };
Function func2 = new Function { Id = 2, Description = "func2" };
FunctionAssignment funcAss1 = new FunctionAssignment
{
Function = func1,
Level = 1
};
FunctionAssignment funcAss2 = new FunctionAssignment
{
Function = func2,
Level = 2
};
// Main test: read properties changed
var propertiesChanged = Utils.GetPublicGenericPropertiesChanged(funcAss1, funcAss2, null);
Assert.IsNotNull(propertiesChanged);
Assert.IsTrue(propertiesChanged.Count == 3);
Assert.IsTrue(propertiesChanged[0].PropertyName == "FunctionAssignment.Function.Description");
Assert.IsTrue(propertiesChanged[1].PropertyName == "FunctionAssignment.Function.Id");
Assert.IsTrue(propertiesChanged[2].PropertyName == "FunctionAssignment.Level");
}