[Resolved] [Resolved] Help with an "if" statement

bigswifty

Im trying to do an if, else loop to perform a function based on weather or not a certain field in a database contains a particular character and its giving me greif, heres what I have....

one field in my returned aray contains a variable string ($isbn) that may or may not contain the letter u or n at the end.

if ($isbn == "%n") {
PRINT "foo"
} ELSEIF ($isbn == "%u") {
PRINT "bar"
} ELSE {
PRINT "something"
}

I know this is wrong, how can I process the string to remove all but the last character to make a new variable ($stripped)
IE:

if ($stripped == "n") {
PRINT "foo"
} ELSEIF ($stripped == "u") {
PRINT "bar"
} ELSE {
PRINT "something"
}

or failing that how can I wildcard the condition (the string will always contain just numbers, (perhaps) hyphens and sometimes the letter u or n at the end -it could in rare occasions be blank-)

1222222222
1222222222u
1-2222-222-22
1-2222-222-22u
1-2222-222-22n

the only conditions I care about is if the string contains a u or n at the end.

many thanks, im sure this is a no brainer, but I just cant seem to find the answer.

Shrike

preg_match("/(.*?[u|n]$)/si", $string, $matches)
  and echo "found a match";

bigswifty

ok thanks.. but what does it mean?

it would be a big help for me if I know what the wild cards are and how that expression is formulated.

i do not want the conditions u and n to result in the same output

if $isbn contains u echo this
if $isbn contains n echo this
else echo something else

unlike many noobs out there I want to understand the solution, not simply get a free code fix.

Thanks again

Shrike

OK 🙂

ignoring the starting and trailing quotes, the backslashes are the expression delimiters. The starting and trailing round brackets put the contained match into a special temporary variable (and also into the $matched array.

.*? - this means any character at all (period), any number of times (star), once(question mark). This is a useful construct (called a non-greedy match) which will match any set of characters up until the next part of the regexp

[u|n] - square brackets denote a grouping of characters. | denotes 'or'. So this part says either u or n.

$ - $ at the end of the regexp denotes 'end of string'. It only means this if it's the last character in the regexp.

hth 🙂

Shrike

Reading the next bit of your post...if all you care about is the very last character and not the whole string, then you could just do

if(substr($string, -1) == "u"){
  do this...
}elseif(substr($string, -1) == "n"){
  do this...
}else{
  do nothing...
}

bigswifty

so I can simply replace [n|u] with n or u?

preg_match("/(.*?n$)/si", $isbn, $matches)
and echo "found a match for n";

preg_match("/(.*?u$)/si", $isbn, $matches)
and echo "found a match for u";

im still unclear how to make use of the results in an "if else"

what I'm trying to do is.

(this is a search results page displaying 20 results per page with forward and back links)

if the isbn for a particular record contains the letter u display this image.

if the isbn for a particular record contains the letter n display this image.

else display nothing

thanks for your help, I'm flipping through my php black book trying to piece this together but I'm still a n00b 🙂

bigswifty

aaaa, The follow up post is much more suited to my task (and this one I understand too 🙂 )

you are correct that all I want to know is if the last char is u, n, or other.

thank you very much thats a winner I think.