Validating number

[I_Love_My_Vans]

I need to validate a number.

nnn.nn.nn

Rules:

Three sections
Each section can contain only numbers
Each section can have any amount of numbers
Each section is seperated by a .


Now i have seen some type of validation, but im not sure how they string together?

Is there any assistance i can get?

ILMV

[visualAd]

You should use a regular expression:

$regexp = "/([0-9]+)\.([0-9]+)\.([0-9]+)/";

if (preg_match($regexp,$string,$matches)) {
    /* matches is now an array contiaing each component*/
    print_r($matches);

} 

[Ecniv]

Can't you split a string entered by a character (I recall - haven't done any php for 3 wks .. might try tonight).
That creates an array - then you check that all the array elements are numeric.
If not - fail it ...
If so - continue on...

Different way

[penagate]

Probably. But remember PHP is a interpreted scripting language. The more you can make the PHP engine do with less code, the better. Efficiency is important on any website, and crucial on high-traffic sites.

[visualAd]

There is a slight over head associated with regular expressions as PHP needs to compile them before executing. This makes the code about 30% slow than loading the string into an array and manually checking each component.

However, once a regular expression has been compiled by the script, it is then cached. When the cached regular expression is used, it is about 60% quicker.

Have a look below at the three tests:

http://adam.codedv.com/examples/speed/speed_test.php

If you run PHP as a module, the compiled regular expressions are shared among scripts. If you are running PHP as a CGI, each expression must be compiled once for each script execution.