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POC# constructor chaining - changing the order of execution
 

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    <p>I want to know how to change the order of execution when chaining constructors in C#. The only methods I have seen require the chained constructor to be called first, outside of the current constructor.</p> <p>Specifically, take the following example:</p> <pre><code>public class Foo { private static Dictionary&lt;string, Thing&gt; ThingCache = new Dictionary&lt;string, Thing&gt;(); private Thing myThing; public Foo(string name) { doSomeStuff(); if (ThingCache.ContainsKey(name)) { myThing = ThingCache[name]; } else { myThing = ExternalStaticFactory.GetThing(name); ThingCache.Add(name, myThing); } doSomeOtherStuff(); } public Foo(Thing tmpThing) { doSomeStuff(); myThing = tmpThing; doSomeOtherStuff(); } } </code></pre> <p>Ideally, I'd like to reduce code repetition by doing this (note, I admit that in this contrived example, not much code is saved, but I am working with code that would benefit much more. I use this example for clarity):</p> <pre><code>public class Foo { private static Dictionary&lt;string, Thing&gt; ThingCache = new Dictionary&lt;string, Thing&gt;(); private Thing myThing; public Foo(string name) { if (ThingCache.ContainsKey(name)) { this(ThingCache[name]); } else { this(ExternalStaticFactory.GetThing(name)); ThingCache.Add(name, myThing); } } public Foo(Thing tmpThing) { doSomeStuff(); myThing = tmpThing; doSomeOtherStuff(); } } </code></pre> <p>This is possible in VB .Net, but C# doesn't let me call a constructor in the middle of another constructor - only at the beginning using the Foo() : this() syntax.</p> <p>So my question is, how does one control the order of constructor calling when chaining constructors, rather than using the colon syntax, which can only call the other constructor first?</p>
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