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C# Dictionary Containskey String Not Working

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C# Dictionary Containskey String Not Working

How do I make an alien technology feel alien? share|improve this answer edited Nov 7 '12 at 2:16 Marko 37.9k19104137 answered Nov 7 '12 at 1:53 Kirill Polishchuk 36.7k76885 It doesn't check this. Otherwise different objects may suddenly have same keys. I have modified your original example to change your fields in PermissionsKey to immutable properties and added a constructor to allow you to set them once when initially created.

  1. To fix it override the Equals method and check if the name values are the same.
  2. Why are auto leases stubbornly strict about visa status and how to work around that?
  3. share|improve this answer edited Jun 10 '10 at 14:09 Sam Holder 23.3k659120 answered Jun 10 '10 at 14:07 Willem van Rumpt 5,20921836 And what if name is null?
  4. I have a class public class MyClass: Dictionary Even though my key value, which is a string is there in the dictionary, myClass.ContainsKey still returns false.
  5. What are you trying to map here?
  6. So why is it having problems matching a basic long key and how do you make it behave?
  7. Why were pre-election polls and forecast models so wrong about Donald Trump?

There is an overload of the Dictionary constructor in which you can provide the specific IEqualityComparer to use. Should I allow my child to make an alternate meal if they do not like anything served at mealtime? Additionally - the hash-code must not change while the item is in the dictionary. C# Iequalitycomparer Maybe it is simpler use string key and to serialize object to strin using BinaryFormatter ?

more hot questions lang-cs about us tour help blog chat data legal privacy policy work here advertising info mobile contact us feedback Technology Life / Arts Culture / Recreation Science Other C# Containskey share|improve this answer edited Jun 10 '10 at 15:01 answered Jun 10 '10 at 13:50 John Gietzen 31.5k22101160 This code isn’t safe (NRE in GetHashCode for one thing) and A good hashcode that follows the Equals implementation will help speed up comparisons by placing only objects with the same hash code into the same buckets. http://stackoverflow.com/questions/27750832/dictionary-containskey-in-c-sharp-is-not-finding-a-key-in-the-dictionary current community chat Stack Overflow Meta Stack Overflow your communities Sign up or log in to customize your list.

Coworker throwing cigarettes out of a car, I criticized it and now HR is involved Giving change in smaller denominations so customers can tip? Gethashcode Implementation C# If you do not want to generally override GetHashCode and Equals on the class, or if you are unable to. class KeyComparer : IEqualityComparer { public bool Equals(Key x, Key y) { return x.Name == y.Name; } public int GetHashCode(Key obj) { return obj.Name.GetHashCode(); } } As it stands, your Key Out of interest, do you have any particular reason to make CacheKey a struct rather than a class?

C# Containskey

The Key class must override Equals in order for the Dictionary to detect if they are the same. http://stackoverflow.com/questions/15905595/c-sharp-dictionary-containskey-trygetvalue-not-working You will see something similar in most object oriented languages. C# Dictionary Containskey String Not Working odd. C# Override Gethashcode ContainsKey does not find existing key in this case.

Note: I tried the same with a list as well (List and the result is the same - the Contains method does not really work with string[]) c# dictionary containskey share|improve http://elliottwaveresearch.com/not-working/css-top-not-working.html If those answers do not fully address your question, please ask a new question. asked 6 years ago viewed 5153 times active 6 years ago Upcoming Events 2016 Community Moderator Election ends in 9 days Get the weekly newsletter! Is there any way for a planet orbiting a red dwarf in the habitable zone to not be tidally locked? C# Gethashcode

Edit: Code. The HashCode defines which "bucket" the object falls into. Anyhow, I have implemented the Equals() and CompareTo() functions, as well as the == and != operators. this contact form Are you asking if this can be null?

How to force ContainsKey to compare object contents and find key? Dictionary C# Where to find sample of this ? For example, if I had a Dictionary(MyObject, int) and MyObject has a public property (of int) called "TypeID", could I get ContainsKey(MyObject myObject) to check to see if one of the

In your PermissionsKey class, you do not override Equals, which means that the default Equals method is still in play (which is the object reference, and is unique for each specific

Is this the expected behaviour? They are not 100% complete and fully functional solutions equipped with error handling. Post your question and get tips & solutions from a community of 418,812 IT Pros & Developers. ContainsKey does not find existing key in this case.

Andrus. Previous examples of large scale protests after Presidential elections in US? stackoverflow.com/questions/263400/… –SLaks Nov 29 '11 at 1:38 Well, I've mentioned that the implementation is quite naive :) Anyway thanks for your comment! navigate here Depends if he want's null keys, but it's a bug as of now :) –simendsjo Jun 10 '10 at 14:14 add a comment| up vote 1 down vote you need to

But seems like it doesn't really check that. In their most basic form: public void Add(long id) { if (AreaDataDict.ContainsKey(id)) return; AreaData ad = new AreaData(id); ad.Load(); AreaDataDict.Add(id, ad); } Also: public void Add(long id) { AreaData areaData; if it turned out that I needed another class that implements only the IEqualityComparer interface and that I have to pass an instance of this second class to the Dictionary constructor. the key is an instance of a class which have 2 values (ie.

I got it where I believe it should work. public class Duration : IEquatable { protected double _length; ///

/// Gets or Sets the duration in Miliseconds. /// public virtual double Length { get { return _length; } For things that are equal (Equals() == true) it must return the same number (but it is permitted to have collisions - i.e. Browse other questions tagged c# dictionary long-integer containskey trygetvalue or ask your own question.

Browse other questions tagged c# authentication dictionary permissions user-permissions or ask your own question. Any clues!!??? Why?) but I still think the advice is backwards.