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    <blockquote> <p>Is there a way to avoid mentioning int.TryParse at all, so that my calls look as follows:</p> </blockquote> <p>Not directly, as <code>TryParse</code> isn't part of a shared interface. If there were a shared interface to these value types, this would be possible via a constraint.</p> <hr> <p>Personally, I would not suggest using extension methods for this. I would rather write this as something more like:</p> <pre><code>public static class Parse { public delegate bool ParseDelegate&lt;T&gt;(string s, out T result); public static T? FromString&lt;T&gt;(string value, ParseDelegate&lt;T&gt; parse) where T : struct { T result; var parsed = parse(value, out result); return parsed ? result : (T?)null; } public static int? ToNullableInt32(string value) { return FromString&lt;int&gt;(value, int.TryParse); } public static double? ToNullableDouble(string value) { return FromString&lt;double&gt;(value, double.TryParse); } } </code></pre> <p>This adds a bit of overhead up front, but allows you to write these very cleanly, ie:</p> <pre><code> int? first = Parse.FromString&lt;int&gt;("1234", int.TryParse); int? second = Parse.ToNullableInt32("1234"); double? third = Parse.ToNullableDouble("1234"); </code></pre> <p>I see little value in putting an extension method, especially on something like <code>string</code> (which is used everywhere), as it "pollutes" the compilation of string itself. You'll see this everywhere you use strings - basically, any time you use this namespace, you'll end up having these parse methods in your intellisense, etc. In addition, this seems more like a "utility" than something that should appear as built-in functionality of string itself, which is why I personally prefer a separate class for it.</p>
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    1. POHow to write generic extension methods?
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    1. USReed Copsey
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    1. COI liked your suggestion, as well as the advice not to extend String. Thx!
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      1. USArne Lund
 

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