使用AutoMapper運行功能，根據其他參數設置多個屬性

Question

我需要幫助，看看AutoMapper是否可以做到這一點。我的代碼已經被簡化了，但它可以解決問題。

public class SourceObject 
{ 
    public string Property1 { get; set; } 
    public string Property2 { get; set; } 
    public string Property3 { get; set; } 

} 

public class DestinationObject 
{ 
    public string Property1 { get; set; } 
    public string Property2 { get; set; } 
    public string Property3 { get; set; } 
    public string Property4 { get; set; } 
    public string Property5 { get; set; } 
    public string Property6 { get; set; } 
} 

var vm = new ViewModel 
{ 
    Objects = Mapper.Map<IList<SourceObject>, IEnumerable<DestinationObject>>(dests) 
}; 

foreach (var destObj in vm.Objects) 
{ 
    Utility.SetupProperties(destObj, new AnotherDependency(), destObj.Property3, 
     someFlag, anotherFlag); 
} 

Property1到Property3是建立由AutoMapper目前。然後我必須遍歷DestinationObjects的列表來設置Property4到Property6帶一個函數，一些額外的標誌。我明白這可能不是AutoMapper的用途，但我真的希望避免兩次循環對象（一次是通過AutoMapper，一次是我自己的）。靜態SetupProperties功能在其他地方使用，所以我想保留它。 AutoMapper可以設置它嗎？感謝您提前提供任何幫助。

Answer 1

這真的取決於發生了什麼裏面Utility.SetupProperties，但也可以通過使用之前和Automapper映射操作後，有一點邏輯的更復雜的映射情況：https://github.com/AutoMapper/AutoMapper/wiki/Before-and-after-map-actions

Mapper.Initialize(cfg => { 
    cfg.CreateMap<SourceObject, DestinationObject>() 
    .BeforeMap((src, dest) => 
    { 
     //Do some work here and set properties. 
    }) 
}); 

Answer 2

通常，您可以使用AfterMap並通過閉包捕獲您想要傳入的其他參數（如第二個wiki示例中所示）。但是，由於您要在集合之間進行轉換，因此在這種情況下，我認爲沒有一種乾淨的方法來處理每個項目。

我已經做了一些挖掘，並且我認爲您可以使用ITypeConverter<TSource, TDestination>來完成您嘗試的轉換。

我不得不做一些猜測實施和使用案例Utility.SetupProperties等，但我認爲概念控制檯應用程序的以下證明應說明如何實現自定義轉換：

using System; 
using System.Collections.Generic; 
using AutoMapper; 

namespace ConsoleApplication 
{ 
    public class Program 
    { 
     public static void Main(string[] args) 
     { 
      var sourceObjects = new SourceObject[] { 
       new SourceObject{Property1 = "prop 1A"}, 
       new SourceObject{Property2 = "Prop 2B"}, 
       new SourceObject{Property3 = "Prop 3C"}}; 

      var someFlag = true; 
      var anotherFlag = false; 

      Mapper.Initialize(cfg => 
      { 
       cfg.CreateMap<SourceObject, DestinationObject>().ConvertUsing<CustomConverter>(); 
      }); 

      var vm = new ViewModel 
      { 
       Objects = Mapper.Map<IList<SourceObject>, IEnumerable<DestinationObject>>(sourceObjects, opts => 
       { 
        opts.Items.Add("AnotherDependency", new AnotherDependency { Foo = "bar" }); 
        opts.Items.Add("flag1", someFlag); 
        opts.Items.Add("flag2", anotherFlag); 
       }) 
      }; 

      foreach (var obj in vm.Objects) 
      { 
       Console.WriteLine($"[{obj.Property1}, {obj.Property2}, {obj.Property3}, {obj.Property4}, {obj.Property5}, {obj.Property6}]"); 
      } 
     } 
    } 

    public class CustomConverter : ITypeConverter<SourceObject, DestinationObject> 
    { 
     public DestinationObject Convert(ResolutionContext context) 
     { 
      return Convert(context.SourceValue as SourceObject, context); 
     } 

     public DestinationObject Convert(SourceObject source, ResolutionContext context) 
     { 
      var dest = new DestinationObject 
      { 
       Property1 = source?.Property1, 
       Property2 = source?.Property2, 
       Property3 = source?.Property3 
      }; 

      var items = context.Options.Items; 

      Utility.SetupProperties(dest, 
       items["AnotherDependency"] as AnotherDependency, 
       dest.Property3, 
       items["flag1"] as bool? ?? false, 
       items["flag2"] as bool? ?? false); 

      return dest; 
     } 
    } 

    public static class Utility 
    { 
     public static void SetupProperties(DestinationObject x, AnotherDependency ad, string a, bool b, bool c) 
     { 
      x.Property4 = ad.Foo; 
      if (b || c) 
      { 
       x.Property5 = ad?.ToString() ?? a; 
      } 
      if (b && c) 
      { 
       x.Property6 = ad?.ToString() ?? a; 
      } 
      return; 
     } 
    } 
    public class ViewModel 
    { 
     public IEnumerable<DestinationObject> Objects { get; set; } 
    } 
    public class AnotherDependency { public string Foo { get; set; } } 
    public class SourceObject 
    { 
     public string Property1 { get; set; } 
     public string Property2 { get; set; } 
     public string Property3 { get; set; } 
    } 
    public class DestinationObject 
    { 
     public string Property1 { get; set; } 
     public string Property2 { get; set; } 
     public string Property3 { get; set; } 
     public string Property4 { get; set; } 
     public string Property5 { get; set; } 
     public string Property6 { get; set; } 
    } 
}