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Dictionary Extensions: Define useful extensions to play safe

, 25 Jan 2012 CPOL
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Useful extensions to play safe.
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    searchTerm = searchCriteria[key];

Ever have a dictionary or similar data structure and your code has many repeated checks to pull the value when in reality you’d be happy with a default value like null or string.Empty? Well, consider the following extension to Dictionary:

public static class DictionaryExtensions
    public static TValue GetSafeValue<TKey, TValue>(this Dictionary<TKey, 
                         TValue> dictionary, TKey key)
        TValue result = default(TValue);
        dictionary.TryGetValue(index, out result);
        return result;

Let’s you do:

Dictionary bob = new Dictionary();
string safe = bob.GetSafeValue(100);

where safe defaults to “” as it hasn’t been added. Stop! I know what you’re going to say and I thought of that too. You can control the default value as well:

public static class DictionaryExtensions
    /// <span class="code-SummaryComment"><summary>

Let’s you do:

Dictionary bob = new Dictionary();
string safe = bob.GetSafeValue(100, null);

where safe is null.

There’s obviously something wrong with me because I still think this stuff is cool.

I’m developing a nice little set of extensions at this point. Often it seems like overkill to encapsulate handy functions like these in a class. I had started by deriving a class from Dictionary<TKey, TValue> but changed over to the above.


This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)


About the Author

Architect Avaya Inc.
Ireland Ireland
Formerly a C++ client developer, nowadays I'm all about C# and ASP.NET. Over the years I have mastered some and played with many aspects of .NET.

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Comments and Discussions

QuestionIf you really want your methods to be "safe"... Pin
Qwertie24-Jan-12 16:07
memberQwertie24-Jan-12 16:07 
AnswerRe: If you really want your methods to be "safe"... Pin
newkie25-Jan-12 2:35
membernewkie25-Jan-12 2:35 
QuestionNaming Pin
Richard Deeming24-Jan-12 6:45
memberRichard Deeming24-Jan-12 6:45 
QuestionGood code! Pin
Member 308248723-Jan-12 20:58
memberMember 308248723-Jan-12 20:58 

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