Typecast each object in an array on a single line of code, using LINQ

Question

Say I've got an array of User:

class User : IUserDowngraded
{
    public Int32 Id { get; set; }
}

... with downgraded functionality done by casting the objects to a specific interface:

interface IUserDowngraded
{
    Int32 Id { get; } // removes set functionality from property
}

... how would I cast those downgraded objects (IUserDowngraded) to User objects in a single line of code, using LINQ?

What I'm trying to avoid is this:

// pseudo-code alert:
IUserDowngraded[] downgradedUsers { IUserDowngraded, IUserDowngraded, ... };

var upgradedUsers = new User[downgradedUsers.Count()];

Int32 i = 0;

foreach (IUserDowngraded du in downgradedUsers)
{
    upgradedUsers[i] = (User)user;

    i++;
}

Noldorin · Accepted Answer · 2009-05-06 00:47:15Z

2

var upgradedUsers = downgradedUsers.Cast<User>();

Append a call to ToArray() if you want upgradedUsers as an array, of course.

answered May 6, 2009 at 0:47

Noldorin

148k56 gold badges273 silver badges308 bronze badges

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

2 Comments

cllpse Over a year ago

Guess I kind'a missed that method. Thanks :)

Noldorin Over a year ago

Yeah, LINQ has lots of goodies that are easy to miss... This is a particularly useful one. :)

Muad'Dib · Accepted Answer · 2009-05-06 00:48:45Z

0

use the cast method....

SampleIntList = SampleStringList.Cast<int>().Select(x => Convert.ToInt32(x)).ToList();

answered May 6, 2009 at 0:48

Muad'Dib

29.4k5 gold badges58 silver badges71 bronze badges

Comments

Community · Accepted Answer · 2017-05-23 12:30:25Z

0

Also any of Implicit operators, Linq and Lambda expressions can make code less readable. But what is more readable? methods should work.

edited May 23, 2017 at 12:30

CommunityBot

11 silver badge

answered May 6, 2009 at 0:49

David McEwing

3,35020 silver badges17 bronze badges

Collectives™ on Stack Overflow

Typecast each object in an array on a single line of code, using LINQ

3 Answers 3

2 Comments

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

2 Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related