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POUsing Closures to keep track of a variable: Good idea or dirty trick?
 

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    <p>Ok, i have a need to be able to keep track of value type objects which are properties on another object, which cannot be done without having those properties implement an IObservable interface or similar. Then i thought of closures and the famous example from Jon Skeet and how that prints out 9 (or 10) a bunch of times and not an ascending order of numbers. So i thought why not do this:</p> <pre><code>Class MyClass { ... Func&lt;MyValueType&gt; variable; ... public void DoSomethingThatGetsCalledOften() { MyValueType blah = variable(); //error checking too not shown for brevity //use it } ... } ... in some other consuming code ... MyClass myClass = new MyClass(); myClass.variable = () =&gt; myOtherObject.MyOtherProperty; //then myClass will get the current value of the variable whenever it needs it </code></pre> <p>Obviously this would require some understanding of how closures work, but my question is this: <strong>is this a good idea or a dirty hack and a misuse of the closure system?</strong></p> <p><strong>Edit:</strong> Since some people seem to be misunderstanding what i'm trying to say, here's a console program which demonstrates it:</p> <pre><code>using System; using System.Linq; namespace Test { class Program { public static void Main() { float myFloat = 5; Func&lt;float&gt; test = () =&gt; myFloat; Console.WriteLine(test()); myFloat = 10; Console.WriteLine(test()); Console.Read(); } } } </code></pre> <p>That will print out <code>5</code> then <code>10</code>.</p>
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    1. COI've edited my answer; hopefully its applicability (or lack thereof!) to your code is a little clearer.
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      1. USAdam Robinson
    2. COPersonally I think you should remove the first example from the question; it doesn't actually relate to your question.
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    3. COI suppose that's a good point.
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