Mapping a list of type string to a list of objects with a string property using automapper

Question

Here is my scenario. I have a class, Class1, with a property of type string[]

Class Class1
{
    string[] strings{ get; set;}
}

and I want to map each string in the list to a string property within a list of type MyClass.

Class MyClass
{
    string someString { get; set;]
}

So, using automapper it would be something like this

Mapper.CreateMap<Class1, IEnumerable<MyClass>>().ForMember(dest => dest.someString, opts => opts.MapFrom(src => src.strings));

I know this won't work but I would imagine it would be something list this. I am not really sure where to go from here or if it is even possible any help would be greatly appreciated.

Andrew Whitaker · Accepted Answer · 2014-10-13 13:06:30Z

4

There are a few ways you could accomplish this:

Use ConstructUsing along with some LINQ:

Mapper.CreateMap<Class1, IEnumerable<MyClass>>()
    .ConstructUsing(
        src => src.strings.Select(str => new MyClass { someString = str }));

Use an "inner" mapping from string to MyClass and call that from ConstructUsing:

Mapper.CreateMap<string, MyClass>()
    .ConstructUsing(str => new MyClass { someString = str });

Mapper.CreateMap<Class1, IEnumerable<MyClass>>()
    .ConstructUsing(src => Mapper.Map<IEnumerable<MyClass>>(src.strings));

Update based on comments:

If you have multiple string[] properties in the source class and multiple corresponding string properties in the destination class, you could do something like this:

Mapper.CreateMap<Class1, IEnumerable<MyClass>>()
    .ConstructUsing(
        src => src.strings
            .Zip(src.strings2, (str1, str2) => new { str1, str2 })
            .Zip(src.strings3, (res1, str3) => 
                new MyClass 
                { 
                    someString = res1.str1,
                    someString2 = res1.str2, 
                    someString3 = str3
                }));

You'd basically call .Zip as many times as you have to. This assumes all of the indexes match up for each array and the number of elements in each array is the same.

edited Oct 13, 2014 at 13:06

answered Oct 10, 2014 at 15:08

Andrew Whitaker

126k32 gold badges296 silver badges308 bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

Chris Over a year ago

As a follow up, how would you do this with multiple properties in the same class?

Andrew Whitaker Over a year ago

In the source or destination? If you update your question I'd be happy to take a look

Chris Over a year ago

The source, class1, contains n properties of type string[] and I want to map them into a list of MyClass that contains n properties of type string. I solved it with a custom resolver but I feel like this can be done without doing that.

Andrew Whitaker Over a year ago

@Chris: I updated my answer. If the number of properties is huge, you might want to look into a custom resolver instead

Collectives™ on Stack Overflow

Mapping a list of type string to a list of objects with a string property using automapper

1 Answer 1

4 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

4 Comments

Your Answer

Sign up or log in

Post as a guest

Related