how to specify if empty=ok or if not empty,must match a regex?

[vijdev]

how to specify:

if (an input field is empty) {

it is OK

dont set $error['input']

}

elseif(matches ^[A-Za-z]{1,15}$) {

it is OK

dont set $error['input']

}

else{

set $error[input']

}

 

in other words match empty or match regex for no error case

[cags]

Using the exactly logic you have laid out you could use...

 

if( empty( $input ) ) {
} elseif( preg_match( '#^[A-Za-z]{1,15}$#', $input ) ) {
} else {
  $error['input'] = 'Something';
} 

A neater way would probably be...

 

if(!empty( $input ) && !preg_match( '#^[A-Za-z]{1,15}$#', $input )) {
   $error['input'] = 'Something';
}

[vijdev]

Using the exactly logic you have laid out you could use...

 

if( empty( $input ) ) {
} elseif( preg_match( '#^[A-Za-z]{1,15}$#', $input ) ) {
} else {
  $error['input'] = 'Something';
} 

A neater way would probably be...

 

if(!empty( $input ) && !preg_match( '#^[A-Za-z]{1,15}$#', $input )) {
   $error['input'] = 'Something';
}

 

thanks, guess that works.

also found a method within regex:

preg_match_all("/(^$)|(^[A-Za-z]{1,15}$)/",$input,$match);

 

what do you think of this OR within the regex?

[cags]

I nearly proffered that as a third option, however it won't actually give quite the same results as using empty(), so I stuck with what you'd actually stated. A value of 0 (or '0') will be considered empty but will fail your Regex, depending on requirements this may be closer to what you want, impossible for me to say. Also why did you use preg_match_all? Given your stated usage preg_match would be the function you want.

[vijdev]

I nearly proffered that as a third option, however it won't actually give quite the same results as using empty(), so I stuck with what you'd actually stated. A value of 0 (or '0') will be considered empty but will fail your Regex, depending on requirements this may be closer to what you want, impossible for me to say. Also why did you use preg_match_all? Given your stated usage preg_match would be the function you want.

 

yes, the 0 should fail, and by my requirment it must be so.but i understand what you are saying in a generic sense.its a new insight-thanks. yes i need preg_match.