I need a regex able to match everything but a string starting with a specific pattern (specifically index.php
and what follows, like index.php?id=2342343
)
7 Answers
Regex: match everything but:
- a string starting with a specific pattern (e.g. any - empty, too - string not starting with
foo
):- Lookahead-based solution for NFAs:
- Negated character class based solution for regex engines not supporting lookarounds:
- a string ending with a specific pattern (say, no
world.
at the end):- Lookbehind-based solution:
- Lookahead solution:
- POSIX workaround:
- a string containing specific text (say, not match a string having
foo
):- Lookaround-based solution:
- POSIX workaround:
- Use the online regex generator at www.formauri.es/personal/pgimeno/misc/non-match-regex
- a string containing specific character (say, avoid matching a string having a
|
symbol): - a string equal to some string (say, not equal to
foo
):- Lookaround-based:
- POSIX:
- a sequence of characters:
- PCRE (match any text but
cat
):/cat(*SKIP)(*FAIL)|[^c]*(?:c(?!at)[^c]*)*/i
or/cat(*SKIP)(*FAIL)|(?:(?!cat).)+/is
- Other engines allowing lookarounds:
(cat)|[^c]*(?:c(?!at)[^c]*)*
(or(?s)(cat)|(?:(?!cat).)*
, or(cat)|[^c]+(?:c(?!at)[^c]*)*|(?:c(?!at)[^c]*)+[^c]*
) and then check with language means: if Group 1 matched, it is not what we need, else, grab the match value if not empty
- PCRE (match any text but
- a certain single character or a set of characters:
- Use a negated character class:
[^a-z]+
(any char other than a lowercase ASCII letter) - Matching any char(s) but
|
:[^|]+
- Use a negated character class:
Demo note: the newline \n
is used inside negated character classes in demos to avoid match overflow to the neighboring line(s). They are not necessary when testing individual strings.
Anchor note: In many languages, use \A
to define the unambiguous start of string, and \z
(in Python, it is \Z
, in JavaScript, $
is OK) to define the very end of the string.
Dot note: In many flavors (but not POSIX, TRE, TCL), .
matches any char but a newline char. Make sure you use a corresponding DOTALL modifier (/s
in PCRE/Boost/.NET/Python/Java and /m
in Ruby) for the .
to match any char including a newline.
Backslash note: In languages where you have to declare patterns with C strings allowing escape sequences (like \n
for a newline), you need to double the backslashes escaping special characters so that the engine could treat them as literal characters (e.g. in Java, world\.
will be declared as "world\\."
, or use a character class: "world[.]"
). Use raw string literals (Python r'\bworld\b'
), C# verbatim string literals @"world\."
, or slashy strings/regex literal notations like /world\./
.
I need a regex able to match everything but except a string starting with
index.php
a specific pattern (specifically index.php and what follows, like index.php?id=2342343)
Use method Exec
let match,
arr = [],
myRe = /([\s\S]+?)(?:index\.php\?id.+)/g;
var str = 'http://regular-viragenia/index.php?id=2342343';
while ((match = myRe.exec(str)) != null) {
arr.push(match[1]);
}
console.log(arr);
var myRe = /([\s\S]+?)(?:index\.php\?id=.+)/g;
var str = 'http://regular-viragenia/index.php?id=2342343';
var matches_array = myRe.exec(str);
console.log(matches_array[1]);
OR OTHER MATCH
let match,
arr = [],
myRe = /index.php\?id=((?:(?!index)[\s\S])*)/g;
var str = 'http://regular-viragenia/index.php?id=2342343index.php?id=111index.php?id=222';
while ((match = myRe.exec(str)) != null) {
arr.push(match[1]);
}
console.log(arr);