[Mono-devel-list] mcs code for switches on strings

[Richard Torkar]

On Sat, 2004-03-20 at 03:17 +0000, Marcus wrote:

> In one of my projects, I have a large number of cases where I make three-way 
> decisions based on a string comparison. I wrote a short test program with a 
> three-way decision using nested if-statements and a switch statement to see 
> which was more efficient. I did have to use a large number of iterations in a 
> loop to get reliable timing numbers, but once I did, I found that using this 
> if-statement in a loop took about 112 ms:
> 
>             if ( list[i] == "Apple" )
>                 x = 1;
>             else if ( list[i] == "Banana" )
>                 x = 2;
>             else
>                 x = 3;
> 
> whereas this switch took about 889 ms:
> 
>             switch ( list[i] )
>             {
>                 case "Apple": x = 1; break;
>                 case "Banana": x = 2; break;
>                 default: x = 3; break;
>             }

Hmm, is it just me or isn't switch/case supposed to execute faster when
comparing several strings like above? I learnt that many years ago, thus
I consequently use switch/case in stead of nested if-statements if it
looks like the above.

Is this not true anymore as a general rule?

/Richard