Go Premium for a chance to win a PS4. Enter to Win

x
?
Solved

heres a tricky question on IDictionary.Contains method

Posted on 2006-11-07
3
Medium Priority
?
497 Views
Last Modified: 2008-01-09
i am making new Hashtable() objects all the time in my project.
however i am making them like so :

IDictionary id = new Hashtable();

my question is in regards to both the .Contains() method in IDictionary and the.ContainsKey() method in hashtable.
according to msdn on .ContainsKey() method:
>
This method behaves exactly as Contains.
This method is an O(1) operation.
>

which potentially means that it is faster.

what i want to know is if i use the .Contains() method will it use the underlining .ContainsKey method and therefore i will get O(1) operation? and can u prove this either way.
0
Comment
Question by:joshuadavidlee
  • 2
3 Comments
 
LVL 13

Expert Comment

by:AngryBinary
ID: 17900495
While either a bechmark test or diassembly is the best way to PROVE this, I think the fact that an index lookup is a non-linear operation implies that any method that essentially and exclusively implements an index lookup (as opposed to an "iterate and search") will be an O(1) operation as well, and going the extra step to demonstrate proof of this is a little excessive unless you have a reeeeeeeeeeeally good reason to suspect otherwise :)

--Randall
0
 
LVL 4

Expert Comment

by:ostdp
ID: 17900905
I just looked into the assembly and I can confirm that Contains calls the ContainsKey method.
0
 
LVL 4

Accepted Solution

by:
ostdp earned 2000 total points
ID: 17900913
This is the code that a decompiler produces:

public virtual bool Contains(object key)
{
      return this.ContainsKey(key);
}

0

Featured Post

Industry Leaders: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

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

In this post we will learn how to make Android Gesture Tutorial and give different functionality whenever a user Touch or Scroll android screen.
In real business world data are crucial and sometimes data are shared among different information systems. Hence, an agreeable file transfer protocol need to be established.
An introduction to basic programming syntax in Java by creating a simple program. Viewers can follow the tutorial as they create their first class in Java. Definitions and explanations about each element are given to help prepare viewers for future …
With the power of JIRA, there's an unlimited number of ways you can customize it, use it and benefit from it. With that in mind, there's bound to be things that I wasn't able to cover in this course. With this summary we'll look at some places to go…

772 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