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Comments on Update list based on presence of identifier in a second list

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Update list based on presence of identifier in a second list

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In C#, I have two lists and need to mark records in the first based on the second. Here's a sample:

public class Vehicle
{
    public string Make { get; set; }
    public string VIN { get; set; }
    public string Color { get; set; }
    public bool HasRegistration { get; set; } = false;
}

The second list is simply a set of VINs (List<string>) that have been registered. I need to mark all the vehicles in the List<Vehicle> which have their VIN somewhere in the List<string>. This is what I have, and it works, but I am looking for something more LINQ.

foreach(var v in vehicles)
{
    if (vinList.Contains(v.VIN))
    {
       v.HasRegistration = true;
    }
}

I could also do v.HasRegistration = (vinList.Contains(v.VIN));

Can this be done in a single, LINQ statement?

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General comments (3 comments)
General comments
FoggyFinder‭ wrote almost 4 years ago

Nope. LINQ is about receiving and not mutating. You could use .ForEach though: vehicles.ForEach(v => v.HasRegistration = vinList.Contains(v.VIN));

FoggyFinder‭ wrote almost 4 years ago

I.e. in practice you can write vehicles.Select(v => v.HasRegistration = vinList.Contains(v.VIN)).ToArray(); or something but you shouldn't do that.

FrankLuke‭ wrote almost 4 years ago · edited almost 4 years ago

@FoggyFinder, if you make that an answer, I'd be glad to accept it. The fact that it can't be done. I have no desire to be too clever.