Is Integer

CSharp · Console

/Program.cs

using System;
using System.Text.RegularExpressions;
using System.Reflection;
					
public class Program
{
	public static void Main()
	{
    	int max = 10000;
    	TimerExpression("TryParse", 
    	() =>
    	{
        	for (int i = 0; i < max; i++)
        	{
            	int value = 0; 
            	Int32.TryParse(i.ToString(), out value);
        	}
    	});
    
    	TimerExpression("Regex", 
    	() =>
    	{
        	for (int i = 0; i < max; i++)
        	{

            	Regex.IsMatch(i.ToString(), @"\d");
        	}
    	});

    	TimerExpression("PHP IsNumeric",
    	() =>
    	{
        	for (int i = 0; i < max; i++)
        	{
            	i.ToString().IsNumeric();
        	}
    	});

    	TimerExpression("Reflections TryParse",
    	() =>
    	{
        	for (int i = 0; i < max; i++)
        	{

            	i.ToString().ParseAs<int>(0);
        	}
    	});
	}

	public static void TimerExpression(string label, Action call)
	{
    	var watch = System.Diagnostics.Stopwatch.StartNew();
    	call.DynamicInvoke();
    	watch.Stop();
    	System.Console.WriteLine(label + " " + watch.ElapsedMilliseconds.ToString());
	}
}

public static class StringExtension
{
   	public static TOutput ParseAs<TOutput>(this string value, TOutput defaultValue)
   	{
       	var type = typeof(TOutput);
        	var tryParseMethod = type.GetMethod("TryParse", BindingFlags.Static | BindingFlags.Public, Type.DefaultBinder, new[] { typeof(string), type.MakeByRefType() }, null);
       	if (tryParseMethod == null) return defaultValue;
   
       	var arguments = new object[] { value, null };
       	return ((bool)tryParseMethod.Invoke(null, arguments)) ? (TOutput)arguments[1] : defaultValue;
   	}

   	static readonly Regex _isNumericRegex =
   	new Regex("^(" +
       	        /*Hex*/ @"0x[0-9a-f]+" + "|" +
           	    /*Bin*/ @"0b[01]+" + "|" +
               	/*Oct*/ @"0[0-7]*" + "|" +
               	/*Dec*/ @"((?!0)|[-+]|(?=0+\.))(\d*\.)?\d+(e\d+)?" +
               	")$");
   	public static bool IsNumeric(this string value)
   	{
       	return _isNumericRegex.IsMatch(value);
   	}

}