如何从默认情况下从ClassMapper <t>继承的类中排除所有虚拟属性?

时间:2016-05-05 18:02:47

标签: c# mapping dapper dapper-extensions

我有很多POCO类,每个类都包含几个虚拟属性。像这样:

public class Policy
{
    public int Id { get; set; }
    public int EntityId { get; set; }
    public int ProgramId { get; set; }

    public string PolicyNumber { get; set; }
    public DateTime EffectiveDate { get; set; }
    public DateTime ExpirationDate { get; set; }

    public virtual Entity Entity{ get; set; }
    public virtual Program Program { get; set; }
    public virtual ICollection<Transaction> Transactions { get; set; }
}

要使Dapper.Extensions正常工作,我需要为每个类编写映射,这很好。我的问题是,如果一个类中有任何virtual属性,它们需要明确标记为忽略,我总是忘记这样做。

public sealed class PolicyMapper : BaseMapper<Policy>
{
    public PolicyMapper()
    {
        Map(p => p.Entity).Ignore();
        Map(p => p.Program).Ignore();
        Map(p => p.Transactions).Ignore();
        AutoMap();
    }
}

如果Dapper.Extensions库在映射到POCO类时会自动排除虚拟属性(如果有),那对我来说会有什么好处。 Automapper有一个类似的扩展(link)。有没有办法为Dapper.Extensions库做到这一点?可能是这样的:

public sealed class PolicyMapper : BaseMapper<Policy>
{
    public PolicyMapper()
    {
        IgnoreAllVirtual();
        AutoMap();
    }
}

1 个答案:

答案 0 :(得分:0)

我找到了自己的解决方案。由于我的所有映射类都派生自BaseMapper类,因此我决定覆盖将排除虚拟属性的AutoMap()方法:

public class BaseMapper<T> : ClassMapper<T> where T : BaseClass
{
    public BaseMapper()
    {

    }

    protected override void AutoMap()
    {
        CustomAutoMap(null);
    }

    private void CustomAutoMap(Func<Type, PropertyInfo, bool> canMap)
    {
        Type type = typeof(T);
        bool hasDefinedKey = Properties.Any(p => p.KeyType != KeyType.NotAKey);
        PropertyMap keyMap = null;

        foreach (var propertyInfo in type.GetProperties())
        {
            // Exclude virtual properties
            if (propertyInfo.GetGetMethod().IsVirtual)
            {
                continue;
            }

            if (Properties.Any(p => p.Name.Equals(propertyInfo.Name, StringComparison.InvariantCultureIgnoreCase)))
            {
                continue;
            }

            if ((canMap != null && !canMap(type, propertyInfo)))
            {
                continue;
            }

            PropertyMap map = Map(propertyInfo);
            if (!hasDefinedKey)
            {
                if (string.Equals(map.PropertyInfo.Name, "id", StringComparison.InvariantCultureIgnoreCase))
                {
                    keyMap = map;
                }

                if (keyMap == null && map.PropertyInfo.Name.EndsWith("id", true, CultureInfo.InvariantCulture))
                {
                    keyMap = map;
                }
            }
        }

        if (keyMap != null)
        {
            keyMap.Key(PropertyTypeKeyTypeMapping.ContainsKey(keyMap.PropertyInfo.PropertyType)
                ? PropertyTypeKeyTypeMapping[keyMap.PropertyInfo.PropertyType]
                : KeyType.Assigned);
        }
    }
}

}