Preg_Match Help

NZ_Kiwis

55. 1 # 2 AKSPI O

I want to get the first letter after # 2 (where the 2 is a variable number 1-9).

HOw can I do that?

johanafm

If the character index position in the string is always the same

$str = '55. 1 # 2 AKSPI O ';

$a = $str[10]

Else, it would depend on how exact you need your patter to be.

Alwys match the first letter, regardless of what comes before it. The letter can even be the first character of the string

# Match zero, one or more non-alpha characters, followed by an alpha character.
# \K resets the capturing to start at this point, so whatever was matched before it
# (non-letters) is discarded and the first captured is a letter
$p = '#[^[:alpha:]]*\K[[:alpha:]]#';

Match first letter but only if there is at least on other non letter character before it.

$p = '#[^[:alpha:]]*\K[[:alpha:]]#';

Match, in this order
1 or more digits
.
1 or more white spaces
1 digit
1 or more whitespaces
#
1 or more whitespaces
1 of digits 1 to 9 (0 excluded)
1 or more whitespaces
(reset capturing to begin here)
letter

$p = '/\d+\.\s+\d\s+#\s+[1-9]\s+\K[[:alpha:]]/';

And it can be made more precise if you know that there is only ever 1 whitespace (or 2, or 3) and not any number of whitespaces.

NogDog

...the first letter after # 2 (where the 2 is a variable number 1-9)

If we take this as the exact requirement, and if it is a given that there will always be exactly one space after the number:

if(preg_match('/(?<=# [1-9] )[a-z]/i', $text, $matches)) {
   echo $matches[0];
}

If the spacing could vary, then the look-behind assertion won't be doable, and you'll have to do something more along the lines of the prior reply, maybe:

if(preg_match('/#\s+[1-9]\s+([a-z])/i', $text, $matches)) {
   // now it's the first sub-pattern:
   echo $matches[1];
}

NZ_Kiwis

What about it i had a string such as

Score for this student was a B John Weston

I have a sub string "John Weston" how can i got back before this with one white space and get the score "B"???

how can i read more on the logic of preg_march?

NZ_Kiwis

I have this where OPI is "Score for this student was a B John Weston from class..."

if (preg_match("# [A-Z] [$StudentName] #", $OPI, $m)) {

against

if substring '# 2 ' is formatted------4 chars only
do this, no need a pcre:

$str = '55. 1 # 2 AKSPI O ';
$a=strpbrk($str, '#');
echo $a[4];