How do I use Linq in MonoDevelop 2.0 on OS X?

Question

I installed MonoDevelop 2.0 on my Mac.

I created a new Console Application.

"Hello World" program runs fine.

But I can't use Linq.

using System. doesn't show Linq option.

What should I do?

score 21 · Accepted Answer · edited Feb 05 '13 at 14:30

21

You may need to right-click on your project in the solution view, do Options, Build, General, and set your Target Runtime to Mono / .Net 3.5 or bigger.

Then you can right-click references, do Edit References, and add a reference to System.Core to your project.

edited Feb 05 '13 at 14:30

Rubens Mariuzzo

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answered May 17 '09 at 23:05

jpobst

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also.. not only the target but YOUR project needs to be 3.5 as well (I had issues where my project was 2.0 and pointing to a mono/net 3.5 proj and it freaked) – KevinDeus Oct 21 '09 at 20:48
Thanks a lot. I knew what how to target the runtime but didn't know that I needed to change the core lib. – Evan Plaice Jun 12 '10 at 03:38

score 6 · Answer 2 · edited Feb 05 '13 at 14:33

6

I'm running Monodevelop 2.0 and Mono 2.0 on Ubuntu 9.04 and lambda's and Linq work fine.

Contrary to what Thomas Levesque says, System.Core does exist in Mono. Extension methods, lambda's et al are all supported.

You need to use using System.Linq.

public static void Example1()    
{

    List<string> people = new List<string>() 
    { 
        "Granville", "John", "Rachel", "Betty", 
        "Chandler", "Ross", "Monica" 
    };

    IEnumerable<string> query = from p in people where p.Length > 5 
    orderby p select p;

    foreach (string person in query) 
    {
        Console.WriteLine(person);
    }
}

edited Feb 05 '13 at 14:33

Rubens Mariuzzo

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answered May 16 '09 at 13:16

Opflash

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Hi, I added 'using System.Linq' and got the following error when I compiled. [Task:File=/Users/ssk/Projects/Test Linq 4/Test Linq 4/Main.cs, Line=17, Column=50, Type=Error, Priority=Normal, Description=An implementation of `Where' query expression pattern could not be found. Are you missing `System.Linq' using directive or `System.Core.dll' assembly reference?(CS1935)] – Sam Kong May 17 '09 at 02:54
What happens when you try to run the example code? Which type are you trying to call Where on? – Opflash May 17 '09 at 10:11

score 1 · Answer 3 · edited Feb 05 '13 at 14:37

1

Is your Console Application referencing the System.Core.dll? You need to reference it in order to use System.Linq.

edited Feb 05 '13 at 14:37

Rubens Mariuzzo

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answered May 15 '09 at 23:22

Jordan S. Jones

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I was missing this DLL. Thanks! – Rubens Mariuzzo Feb 05 '13 at 14:28

score 1 · Answer 4 · answered May 19 '09 at 02:34

1

The Latest version of Mono Develop does support linq. On the project you must select 3.5 under Build/General/RuntimeVersion. After that you can add the System.Core reference.

answered May 19 '09 at 02:34

Subtle Fox · Answer 5 · 2013-08-20T09:19:26.763

0

Check if your project references on System.Xml.Linq library too

edited Aug 20 '13 at 09:19

answered Apr 25 '13 at 12:22

Subtle Fox

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score -2 · Answer 6 · answered May 16 '09 at 13:10

-2

Not sure LINQ is fully implemented within the current release http://www.mono-project.com/Roadmap

answered May 16 '09 at 13:10

Cargowire

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How do I use Linq in MonoDevelop 2.0 on OS X?

6 Answers6

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