string.lenght vs string.empty

[Guest]

Hi,
I read that to check for empty strings , comparing strings using
String.Length == 0 is faster than String.Empty or "" . Is it true...?
If so, how?

 

[Hans Kesting]

Hi,
I read that to check for empty strings , comparing strings using
String.Length == 0 is faster than String.Empty or "" . Is it true...?
If so, how?

I think it is faster because:
* Length is stored, doesn't need to be calculated
* integer comparison (Length == 0) is easier that string comparison,
which (I think) needs to be done on a character-by-character basis.

Hans Kesting

 

[Roger Helliwell]

Hi,
I read that to check for empty strings , comparing strings using
String.Length == 0 is faster than String.Empty or "" . Is it true...?
If so, how?

I think str.Length is probably faster, however if your string is null,
using Length will throw a NRE. I prefer to use
string.IsNullOrEmpty(someString). It safely works on null strings as
well as empty strings.

Roger

 

[Patrice]

Under normal circumstances it's unlikely to give a perceptible difference...

You could easily measure and see what the IL is...

Patrice

 

[Steve C. Orr [MVP, MCSD]]

It is true that checking the String.Length is faster.
Numeric functions are almost always more efficient than string functions.