自动映射器:映射集合和传递参数

本文介绍了自动映射器:映射集合和传递参数的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我正在尝试将一个实体映射到另一个(具有一个附加字段).

I am trying to map one entity to another (which has one additional field).

Group { int Id; } GroupExtended { int Id; string Description; }

所以我在循环中进行映射:

So I do the mapping in loop:

foreach (var group in groups) { var result = mapper.Map<Group, GroupExtended>(group, opt => opt.AfterMap((src, dest) => dest.Description = someValue)); }

是否可以映射整个IEnumerable，并且仍传递值?我试过了:

Is that possible to map entire IEnumerable, and still passing an the value ? I tried this:

var result = mapper.Map<List<GroupExtended>>(groups, opt => opt.AfterMap((src, dest) => dest.Description = someValue));

但是在 dest.Description 上有错误:'object'不包含"Description"的定义

But it has an error on dest.Description : 'object' does not contain definition of "Description"

推荐答案

是的，可以映射整个集合并仍然传递值.首选使用自定义值解析器，因为在您对原始帖子的评论中指出.如果仍然希望使用 AfterMap ，则可以执行以下操作，请记住，在这种情况下，您的源和目标是集合，而不是单个项目:

Yes, it is possible to map an entire collection and still pass the value. Using a custom value resolver is probably the preferred option, as pointed out in the comment on your original post. If you'd still prefer to use AfterMap, you can do something like the following, remembering that your source and destination in this case are collections rather than individual items:

var result = mapper.Map<List<Group>, List<GroupExtended>>(groups, opt => opt.AfterMap((src, dest) => { foreach (var i in dest) { i.Description = "someValue"; } }));