使用 C# 比较嵌套对象属性 [英] Comparing Nested object properties using C#

问题描述

我有一个方法可以比较两个对象并返回所有不同属性名称的列表.

I have a method which compares two objects and returns a list of all the property names which are different.

public static IList<string> GetDifferingProperties(object source, object target)
{
    var sourceType = source.GetType();
    var sourceProperties = sourceType.GetProperties();
    var targetType = target.GetType();
    var targetProperties = targetType.GetProperties();

    var properties = (from s in sourceProperties
                      from t in targetProperties
                      where s.Name == t.Name &&
                            s.PropertyType == t.PropertyType &&
                            s.GetValue(source,null) != t.GetValue(target,null)
                      select s.Name).ToList();
    return properties;
}

例如，如果我有两个类，如下所示:

For example if I have two classes as follows:

public class Address
    {
        public string AddressLine1 { get; set; }
        public string AddressLine2 { get; set; }
        public string City { get; set; }
        public string State { get; set; }
        public string Zip { get; set; }
    }

       public class Employee
        {
            public string FirstName { get; set; }
            public string MiddleName { get; set; }
            public string LastName { get; set; }
            public Address EmployeeAddress { get; set; }
        }

我正在尝试比较以下两个员工实例:

I am trying to compare the following two employee instances:

var emp1Address = new Address();
        emp1Address.AddressLine1 = "Microsoft Corporation";
        emp1Address.AddressLine2 = "One Microsoft Way";
        emp1Address.City = "Redmond";
        emp1Address.State = "WA";
        emp1Address.Zip = "98052-6399";

        var emp1 = new Employee();
        emp1.FirstName = "Bill";
        emp1.LastName = "Gates";
        emp1.EmployeeAddress = emp1Address;


        var emp2Address = new Address();
        emp2Address.AddressLine1 = "Gates Foundation";
        emp2Address.AddressLine2 = "One Microsoft Way";
        emp2Address.City = "Redmond";
        emp2Address.State = "WA";
        emp2Address.Zip = "98052-6399";

        var emp2 = new Employee();
        emp2.FirstName = "Melinda";
        emp2.LastName = "Gates";
        emp2.EmployeeAddress = emp2Address;

因此，当我当前将这两个员工对象传递给我的 GetDifferingProperties 方法时，它返回 FirstName 和 EmployeeAddress，但它没有告诉我 EmployeeAddress 中的哪个确切属性(在本例中为 Address1)已更改.如何调整此方法以获得类似 EmployeeAddress.Address1 的内容?

So when I pass these two employee objects to my GetDifferingProperties method currently it returns FirstName and EmployeeAddress, but it does not tell me which exact property (which in this case is Address1) in the EmployeeAddress has changed. How can I tweak this method to get something like EmployeeAddress.Address1?

推荐答案

这是因为您使用了 !=，对于对象，它测试对象的身份而不是其值.关键是使用递归生成属性的属性列表.这将随您的需要深入......

It's because you are using != which, for objects, tests the identity of an object rather than its value. The key is to use recursion to generate the list of properties of properties. This will go as deep as you want...

public static IList<string> GetDifferingProperties(object source, object target)
{
  var sourceType = source.GetType();
  var sourceProperties = sourceType.GetProperties();
  var targetType = target.GetType();
  var targetProperties = targetType.GetProperties();

  var result = new List<string>();

  foreach (var property in
      (from s in sourceProperties
       from t in targetProperties
       where s.Name == t.Name &&
       s.PropertyType == t.PropertyType &&
       !Equals(s.GetValue(source, null), t.GetValue(target, null))
       select new { Source = s, Target = t }))
  {
    // it's up to you to decide how primitive is primitive enough
    if (IsPrimitive(property.Source.PropertyType))
    {
      result.Add(property.Source.Name);
    }
    else
    {
      foreach (var subProperty in GetDifferingProperties(
          property.Source.GetValue(source, null),
          property.Target.GetValue(target, null)))
      {
        result.Add(property.Source.Name + "." + subProperty);
      }
    }
  }

  return result;
}

private static bool IsPrimitive(Type type)
{
  return type == typeof(string) || type == typeof(int);
}

这篇关于使用 C# 比较嵌套对象属性的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！