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Questions tagged [idictionary]

System.Collections.IDictionary and System.Collections.Generic.IDictionary interfaces in the BCL (Base Class Library) of the .NET framework represent a collection of key-value pairs.

System.Collections.IDictionary and System.Collections.Generic.IDictionary<TKey, TValue>interfaces in the BCL (Base Class Library) of the .NET framework represent a collection of key-value pairs.

MSDN links:

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Recreating a Dictionary from an IEnumerable>

I have a method that returns an IEnumerable>, but some of the callers require the result of the method to be a dictionary. How can I convert the IEnumerable> into a Dictionary
learnerplates
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Convert List of KeyValuePair into IDictionary "C#"

My scenario, how to convert List> into IDictionary?
anbuselvan
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Why doesn't the C# Dictionary implement all of IDictionary?

I wanted to create a Dictionary-like object and thought the correct way would be to implement the IDictionary interface, and use composition to include the underlying dictionary. I began with the below (K=string, V=int) public class…
Marc Meketon
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Dictionary.ContainsKey() - How does it work?

I've read the MSDN documentation on how Dictionary.ContainsKey() works, but I was wondering how it actually makes the equality comparison? Basically, I have a dictionary keyed to a reference type* and I want the ContainsKey() method to check a…
Richard
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Create a Dictionary in xaml?

Pseudo example: …
Shimmy Weitzhandler
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How to iterate through keys and values of an `IDictionary`?

How would I iterate through the keys and values of an IDictionary if I don't know the concrete types of the keys and values within, therefore want to just treat them as objects? If I do something like: foreach(var x in myIDictionary) { ... } I think…
Joseph Humfrey
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How to initialize a ConcurrentDictionary? Error: "Cannot access private method 'Add' here"

I have a static class in which I am using dictionaries as lookup tables to map between .NET types and SQL types. Here is an example of such a dictionary: private static readonly Dictionary SqlServerMap = new Dictionary { …
Drew
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Why does Dictionary.ContainsKey throw ArgumentNullException?

The documentation states that bool Dictionary.ContainsKey(TKey key) throws an exception in case a null key is passed. Could anyone give a reason for that? Wouldn't it be more practical if it just returned false?
Marcin Kaczmarek
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Need an IDictionary implementation that will allow a null key

Basically, I want something like this: Dictionary dict = new Dictionary(); dict.Add(null, "Nothing"); dict.Add(1, "One"); Are there any built into the base class library that allow this? The preceding code will…
Clyde
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Extension methods for both IDictionary and IReadOnlyDictionary

My question is similar to the previous one, but the answer to that question is inapplicable to this one. Well, I want to write an extension method for both IDictionary and IReadOnlyDictionary interfaces: public static TValue? GetNullable
user1067514
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Is there a limit to entries in a Dictionary<>?

I have about 3000 different files I need to organize, and retrieve at different times during the game. I created my own struct of variables. I was thinking about creating a "Dictionary " at the beginning of my application, and simply loading all my…
theoneawaited
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Getting values of a generic IDictionary using reflection

I have an instance that implements IDictionary, I don't know T and K at compiletime, and want to get all elements from it. I don't want to use IEnumerable for some reason, which would be the only non-generic interface implemented by…
Stefan Steinegger
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Can't view Dictionary contents in Visual Studio debugger

I have a System.Collections.Generic.Dictionary object in my code and am trying to view its contents while stopped at a breakpoint in the Visual Studio debugger. The Dictionary class in .NET of course contains a list of keys and values. If I…
Buggieboy
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When SortedDictionary is enumerated does it return KeyValuePairs in expected order?

When I have SortedDictionary in .NET and I want to enumerate it as ICollection> does it enumerate in expected order? That is KeyValuePair with lowest key is returned as first, folloved by KeyValuePair…
Rasto
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c# Dictionary how to loop through items without knowing key

I have a: var selectedDates = new Dictionary(); selectedDates.Add("2014-06-21", DateTime.Now.ToLongDateString()); selectedDates.Add("2014-07-21", DateTime.Now.AddDays(5).ToLongDateString()); selectedDates.Add("2014-08-21",…
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