Solved

I need to create an extension that completes Contains

Posted on 2011-02-16
5
311 Views
Last Modified: 2013-11-26
Hello,

   How can I create an extension to convert a string in many conditions in the Where part of a Linq. Look at this example:

   from x in data where x.name.MyFunction("john Mary")...

   My function should translate this to:

   from x in data where x.name.Contains("john") || x.name.Contains("Mary") ...

   I belive that the extension is like this, but I'm stuck!

  public MyFunction(string str)
  {
    foreach (var element in str.ToUpper().Split(" "))
    {
        ....            
    }
}

  Can someone help me?

  Thanks,
  Marco Castro
0
Comment
Question by:MarcoCastro
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 3
5 Comments
 
LVL 11

Expert Comment

by:jasonduan
ID: 34906812
To create an extension method, you need create a static class.


public static class MyExtensionClass
{
     public static bool MyContains(this string str)
     {
        foreach (var element in str.ToUpper().Split(" "))
        {
            ....            
        }
    }
}



Note: "Contains" is already a method of string provided by .net framework, so you need use a different name other than "Contains"
0
 
LVL 52

Expert Comment

by:Carl Tawn
ID: 34906815
If you wanted to call your method "Include" then you could use:
    public static class Helpers
    {
        public static bool Includes(this string source, string value)
        {
            string[] values = value.Split(' ');
            foreach (string val in values)
                if (source.Contains(val))
                    return true;

            return false;
        }
    }

Open in new window

0
 

Author Comment

by:MarcoCastro
ID: 34907037
Carl,

  I need something like this. Your code don't works because the Linq Entity (I use FireBird) don't know how to transle this code to a SQL statement. Isn't possible to return a Linq Contains based function? Like this:

   data.Includes("a b")

   should returns

   data.Contains("a") || data.Contans("b") -- this code will de translated by the Linq Entity

   Thanks,
   Marco Castro
0
 

Accepted Solution

by:
MarcoCastro earned 0 total points
ID: 34991689
0
 

Author Closing Comment

by:MarcoCastro
ID: 35034601
I got the answer to my question by myself.
0

Featured Post

On Demand Webinar - Networking for the Cloud Era

This webinar discusses:
-Common barriers companies experience when moving to the cloud
-How SD-WAN changes the way we look at networks
-Best practices customers should employ moving forward with cloud migration
-What happens behind the scenes of SteelConnect’s one-click button

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

This article shows how to deploy dynamic backgrounds to computers depending on the aspect ratio of display
This article aims to explain the working of CircularLogArchiver. This tool was designed to solve the buildup of log file in cases where systems do not support circular logging or where circular logging is not enabled
This tutorial covers a step-by-step guide to install VisualVM launcher in eclipse.
The viewer will learn how to synchronize PHP projects with a remote server in NetBeans IDE 8.0 for Windows.

695 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question