What this 'null' check doing here...

[Brisingr Aerowing]

:doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh: :doh:

[Thomas Daniels]

Arrrggghhhh! My eyes! :eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::eek::

[vonb]

Well, the null has really nothing to do there. Check if(employees.Count()==0) I would do like this

class TestClass()
{
List employees { get; set; }

 TestClass()
 {
      employees = GetEmployees();
 }

 private List GetEmployees()
 {
      return (from oRec in DataModel.Employees select oRec).ToList();
 }

}

The signature is in building process.. Please wait...

[Mohammed Hameed]

Thanks.

Previous -> Read "CLR via C#" by Jeffrey Ritcher. Current -> Exploring WCF thru Apress' "Pro WCF" by Chris Peiris and Dennis Mulder. Next -> Need to read "The Art of Computer Programming" by Donald E. Knuth.

[Richard Deeming]

vonb wrote:

return (from oRec in DataModel.Employees select oRec).ToList();

Why do so many people insist on adding a pointless "from x in source select x" query to their code, when it has the same result as the much more concise "source"?

private List<Employee> GetEmployees()
{
return DataModel.Employees.ToList();
}

---

"These people looked deep within my soul and assigned me a number based on the order in which I joined." - Homer

[vonb]

This was just a simple implementation of more complex queries which I actually use

publc List GetEmployees(int departmentId)
{
return (from oRec in DataModel.Employees where oRec.DepartmentID == departmentId).ToList();
}

The signature is in building process.. Please wait...

[ZurdoDev]

Do you two realize how much money you just cost CP with this waste of disk space? You better click on some ads to pay for your mistakes.

There are only 10 types of people in the world, those who understand binary and those who don't.

[Richard Deeming]

That's one of the reasons why I tend to prefer the method-call syntax for most LINQ queries - if you remove the .Where(filter) clause, your code still looks sensible.

return DataModel.Employees.Where(oRec => oRec.DepartmentID == departmentId).ToList();

---

"These people looked deep within my soul and assigned me a number based on the order in which I joined." - Homer

[Johnny YYZ]

You owe me for the bandwidth cost of 2396 unnecessary :doh:s! Only the icon has 831 bytes, which amounts to a total of 1,991,076 wasted bytes. Gotta count now the extra html chars and send you the invoice! :doh: :sigh: :laugh:

[David C Thompson]

Probably code that has been edited and then not refactored. No real wtf here, ey?

[bencr]

It isn't really filling the list, it's replacing the reference with the result of that method call. I don't think that's what he meant though. A bit pedantic, I'm sorry.

[englebart]

More like the garbage collector...

[Mark Starr]

Guess I don't know c# well enough, but I didn't this you could use any comparison operator against NULL. it's probably bad practice to even if the language allows it.

[GrumpyPants]

Check your version control. It's possible declaration and/or the assignment at declaration was added later. If an earlier version of the method had the List passed as a parameter, then the test for non-null would make sense.

[RafagaX]

I bet the person who wrote this comes from a C/C++ background, there, you have to check for null every time or you may blow out something...

CEO at: - Rafaga Systems - Para Facturas - Modern Components for the moment...

[Michael Losinski]

The only thing that I can think of is technically new doesn't guarantee that the variable initialization will take place. In programming languages like c++ it could return null. This could happen if the memory was so fragmented that the allocation failed. However, instead of returning null in C# I believe it throws a out of memory exception. I have only seen this done in system critical embedded systems.

[Nilesh Shahane]

He is just double checking. :)

[peterchen]

That's a real conundrum for the GC - "OK, if this object is still around, at this point, I can't GC it until then. But... but what if I ... secretlly GC it before the if?"

ORDER BY what user wants

[MainFrameMan_ALIVE_AND_WELL]

Looks like a newbie whose prof in 101 programming hammered down checking objects before using them. This would be sensible if it were a thousand lines down in the code, but, if it is null where is the property/method to new it up?

[KP Lee]

Pete O'Hanlon wrote:

I was reading != as == here

Thanks for the explanation, for a normally sensible person, I was wondering what you were smoking or what I missed with your prior comment too.