What is the fastest way to count newlines in a large .NET string?

Question

Is there a way to improve this:

private static int CountNewlines(string s)
{
    int len = s.Length;
    int c = 0;
    for (int i=0; i < len;  i++)
    {
           


        

Answer 1

Well, String implements IEnumerable, so I'd definitely try:

s.Count( c => c == '\n' )

As nice as this looks, the original method is 30x faster :)

I haven't given up on the IEnumerable yet, so I've also tried:

int n = 0;
foreach( var c in s )
{
    if ( c == '\n' ) n++;
}
return n;

which seems as fast as the original method.