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POBest way to convert IEnumerable<char> to string?
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  1. POBest way to convert IEnumerable<char> to string?
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    copied!<p>Why isn't it possible to use fluent language on <code>string</code>?</p> <p>For example:</p> <pre><code>var x = "asdf1234"; var y = new string(x.TakeWhile(char.IsLetter).ToArray()); </code></pre> <p>Isn't there a better way to convert <code>IEnumerable&lt;char&gt;</code> to <code>string</code>?</p> <p>Here is a test I've made:</p> <pre><code>class Program { static string input = "asdf1234"; static void Main() { Console.WriteLine("1000 times:"); RunTest(1000, input); Console.WriteLine("10000 times:"); RunTest(10000,input); Console.WriteLine("100000 times:"); RunTest(100000, input); Console.WriteLine("100000 times:"); RunTest(100000, "ffff57467"); Console.ReadKey(); } static void RunTest( int times, string input) { Stopwatch sw = new Stopwatch(); sw.Start(); for (int i = 0; i &lt; times; i++) { string output = new string(input.TakeWhile(char.IsLetter).ToArray()); } sw.Stop(); var first = sw.ElapsedTicks; sw.Restart(); for (int i = 0; i &lt; times; i++) { string output = Regex.Match(input, @"^[A-Z]+", RegexOptions.IgnoreCase).Value; } sw.Stop(); var second = sw.ElapsedTicks; var regex = new Regex(@"^[A-Z]+", RegexOptions.IgnoreCase); sw.Restart(); for (int i = 0; i &lt; times; i++) { var output = regex.Match(input).Value; } sw.Stop(); var third = sw.ElapsedTicks; double percent = (first + second + third) / 100; double p1 = ( first / percent)/ 100; double p2 = (second / percent )/100; double p3 = (third / percent )/100; Console.WriteLine("TakeWhile took {0} ({1:P2}).,", first, p1); Console.WriteLine("Regex took {0}, ({1:P2})." , second,p2); Console.WriteLine("Preinstantiated Regex took {0}, ({1:P2}).", third,p3); Console.WriteLine(); } } </code></pre> <p>Result:</p> <pre><code>1000 times: TakeWhile took 11217 (62.32%)., Regex took 5044, (28.02%). Preinstantiated Regex took 1741, (9.67%). 10000 times: TakeWhile took 9210 (14.78%)., Regex took 32461, (52.10%). Preinstantiated Regex took 20669, (33.18%). 100000 times: TakeWhile took 74945 (13.10%)., Regex took 324520, (56.70%). Preinstantiated Regex took 172913, (30.21%). 100000 times: TakeWhile took 74511 (13.77%)., Regex took 297760, (55.03%). Preinstantiated Regex took 168911, (31.22%). </code></pre> <p>Conclusion: I'm doubting what's better to prefer, I think I'm gonna go on the <code>TakeWhile</code> which is the slowest only on first run.</p> <p>Anyway, my question is if there is any way to optimize the performance by restringing the result of the <code>TakeWhile</code> function.</p>
 

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