これがあなたが求めているものだと思います。
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using AutoMapper;
using NUnit.Framework;
namespace StackOverFlowAnswers
{
public class LineItem
{
public int Id { get; set; }
public string ProductId { get; set; }
public int Amount { get; set; }
}
public class Model
{
public int Id { get; set; }
public string ProductId { get; set; }
public string Amount { get; set; }
}
public class AutoMappingTests
{
[TestFixtureSetUp]
public void TestFixtureSetUp()
{
Mapper.CreateMap<Model, LineItem>()
.ForMember(x => x.Amount, opt => opt.ResolveUsing<StringToInteger>());
}
[Test]
public void TestBadStringToDefaultInteger()
{
// Arrange
var model = new Model() {Id = 1, ProductId = "awesome-product-133-XP", Amount = "EVIL STRING, MWUAHAHAHAH"};
// Act
LineItem mapping1 = Mapper.Map<LineItem>(model);
// Assert
Assert.AreEqual(model.Id, mapping1.Id);
Assert.AreEqual(model.ProductId, mapping1.ProductId);
Assert.AreEqual(0, mapping1.Amount);
// Arrange
model.Amount = null; // now we test null, which we said in options to map from null to -1
// Act
LineItem mapping2 = Mapper.Map<LineItem>(model);
// Assert
Assert.AreEqual(-1, mapping2.Amount);
}
}
public class StringToInteger : ValueResolver<Model, int>
{
protected override int ResolveCore(Model source)
{
if (source.Amount == null)
{
return -1;
}
int value;
if (int.TryParse(source.Amount, out value))
{
return value; // Wahayy!!
}
return 0; // return 0 if it could not parse!
}
}
}