Question

I have a struct that I created specific for a usercontrol. My thought was that I would have a public property Guid Dictionary<string, Guid> Attachments and then convert that to my private List<Attachment> attachments on the setter. I’m having trouble doing that, preferably with linq but I’m open to alternatives. Thank you…

private List<Attachment> attachments;
public struct Attachment
{
    public Guid Id { get; set; }
    public string Name { get; set; }
}
public Dictionary<string, Guid> Attachments
{
    get { return attachments.ToDictionary(a => a.Name, a => a.Id); }
    set { attachments = new List<Attachment> // not sure what to do here }
}

Answer 1

Assuming this is a valid design (I haven’t really thought about it) I suspect you want:

attachments = value.Select(pair => new Attachment { Id = pair.Value,
                                                    Name = pair.Key })
                   .ToList();

I would strongly discourage you from using a mutable struct though. Using a struct isn’t too bad in itself, but I’d change it to:

public struct Attachment
{
    private readonly Guid id;
    private readonly String name;

    public Guid Id { get { return id; } }
    public string Name { get { return name; } }

    public Attachment(Guid id, string name)
    {
        this.id = id;
        this.name = name;
    }
}

… at which point the conversion is just:

attachments = value.Select(pair => new Attachment(pair.Value, pair.Key))
                   .ToList();