刚才看到一个关于字符串反转的例子

刚才看到一篇关于字符串反转的文章,原文地址

http://www.cnblogs.com/Mars_Chen/archive/2010/03/04/1678123.html

当时第一感觉是用Array类的reverse方法多好，何必用正则这么麻烦呢？要知道正则虽然看起来简单，但是真正匹配起来可也不容易，于是便一时好奇把这两种方法比较了一下，谁知不比不知道，一比吓一跳啊。下面看代码和结果

static void Main(string[] args)
{
Stopwatch sw = new Stopwatch();
Stopwatch swavg = new Stopwatch();
swavg.Start();
for (int j = 0; j < 10; j++)
{
sw.Start();
for (int i = 0; i < 100000; i++)
{
Reverse1("Who will be faster? Yours or mine? Do you really mind my test?");
}
sw.Stop();
Console.WriteLine("My Method --- Each time:" + sw.Elapsed.ToString());
sw.Reset();

}
swavg.Stop();

 

Console.WriteLine("My Method --- Avg time:" +(sw.ElapsedMilliseconds/10).ToString());

swavg.Reset();
swavg.Start();
for (int j = 0; j < 10; j++)
{
sw.Start();
for (int i = 0; i < 100000; i++)
{
Reverse2("Who will be faster? Yours or mine? Do you really mind my test?");
}
sw.Stop();
Console.WriteLine("Your Method --- Each time:" + sw.Elapsed.ToString());
sw.Reset();

}
swavg.Stop();

Console.WriteLine("Your Method --- Avg time:" + (sw.ElapsedMilliseconds / 10).ToString());

Console.ReadLine();


}
static string Reverse1(string original)
{
char[] arr = original.ToCharArray();
Array.Reverse(arr);
return new string(arr);
}
static string Reverse2(string original)
{
string result = "";
MatchCollection mc = Regex.Matches(original, @"(\S)+");
for (int i = mc.Count - 1; i >= 0; i--)
{
result += mc[i].Value;

}
return result;
}

 

执行结果

My Method --- Each time:00:00:00.0304430
My Method --- Each time:00:00:00.0258621
My Method --- Each time:00:00:00.0243496
My Method --- Each time:00:00:00.0272635
My Method --- Each time:00:00:00.0394696
My Method --- Each time:00:00:00.0242083
My Method --- Each time:00:00:00.0291635
My Method --- Each time:00:00:00.0289069
My Method --- Each time:00:00:00.0243922
My Method --- Each time:00:00:00.0263951
My Method --- Avg time:28
Your Method --- Each time:00:00:01.6769779
Your Method --- Each time:00:00:01.6586320
Your Method --- Each time:00:00:01.6922838
Your Method --- Each time:00:00:01.6572740
Your Method --- Each time:00:00:01.6599065
Your Method --- Each time:00:00:01.6630039
Your Method --- Each time:00:00:01.7182288
Your Method --- Each time:00:00:01.9108913
Your Method --- Each time:00:00:01.7913726
Your Method --- Each time:00:00:01.7917344
Your Method --- Avg time:1722