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Dynamic Thyristor Casting in a Custom Injection ValueInjecter

I created my own injection class for ValueInjecter , which performs recursive injection for shared child collections, but works with existing targets and not cloning, like the "CloneInjection" sample on site VI. However, I am currently using a well-known type (ICollection <MyTargetType>), so the injection class is suitable for only one hard-coded type. It seems I can’t imagine a way to dynamically generalize, any suggestions? Here is the SetValue code for my "RecursiveInjection" class.

//for value types and string just return the value as is
if (c.SourceProp.Type.IsValueType || c.SourceProp.Type == typeof(string))
  return c.SourceProp.Value;

if (c.SourceProp.Type.IsGenericType)
  {
  //handle IEnumerable<> also ICollection<> IList<> List<>
  if (c.SourceProp.Type.GetGenericTypeDefinition().GetInterfaces().Contains(typeof(IEnumerable)))
    {
      var t = c.TargetProp.Type.GetGenericArguments()[0];
      if (t.IsValueType || t == typeof(string)) return c.SourceProp.Value;

      //get enumerable object in target
     var targetCollection = c.TargetProp.Value as ICollection<MyTargetType>;
     //possible to cast dynamically?

     foreach (var o in c.SourceProp.Value as IEnumerable)
     {
       //get ID of source object
       var sourceID = (int)o.GetProps().GetByName("ID").GetValue(o);
       //find matching target object if there is one
       var target = targetCollection.SingleOrDefault(x => x.ID == sourceID);
       if (target != null)
       {
         target.InjectFrom<RecursiveInjection>(o);
       }
     }
    return targetCollection;
  }
}

Thanks DanO

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3 answers

ICollection Equals (object) .

public class MyTargetType
{
    public override bool Equals( object obj )
    {
        return ( obj is MyTargetType )
                    ? this.ID == ( ( MyTargetType ) obj ).ID
                    : false;
    }
}

, .

var target = targetCollection.SingleOrDefault( x => x.Equals( o ) );
+1

, , , EF POCO, (- " " ).

EF 4.0 EF 4.1, ! EF 4.1 . CloneInjection .

+1

I think this is what you are looking for:

    public class M1
    {
        public string Name { get; set; }
    }

    public class M2
    {
        public string Name { get; set; }
    }

    [Test]
    public void Cast()
    {
        object source = new List<M1> {new M1 {Name = "o"}};
        object target = new List<M2>();


        var targetArgumentType = target.GetType().GetGenericArguments()[0];

        var list = Activator.CreateInstance(typeof(List<>).MakeGenericType(targetArgumentType));
        var add = list.GetType().GetMethod("Add");

        foreach (var o in source as IEnumerable)
        {
            var t = Activator.CreateInstance(targetArgumentType);
            add.Invoke(list, new[] { t.InjectFrom(o) });
        }

        target = list;

        Assert.AreEqual("o", (target as List<M2>).First().Name);
    }

with .NET 4 you can make it a little shorter using dynamic

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