I've some text that i wish to parse
$str = "text1<br/>text2<br/>text3
I've tried using
print_r( preg_split("<br/>", $str));
but it is not giving me the desired output
Try the following:
$str = "text1<br/>text2<br/>text3";
print_r(preg_split("/<br\/>/", $str));
I'm assuming missing the closing quote " at the end of the $str = "text1<br/>text2<br/>text3" is just a typo.
Take a look at this page on how to specify the string $pattern parameter: http://php.net/manual/en/function.preg-split.php
It's because you're not using the correct regular expression. Is there a reason you can't use explode()? Regex is problematic, overly complicated at times, and much slower. If you know you'll always be splitting at the BR tag, explode is much more efficient.
Parsing HTML with regex is a bad idea, but here you go:
var_dump(preg_split('/(<br\ ?\/?>)+/', $str));
Related
So I've seen a couple articles that go a little too deep, so I'm not sure what to remove from the regex statements they make.
I've basically got this
foo:bar all the way to anotherfoo:bar;seg98y34g.?sdebvw h segvu (anything goes really)
I need a PHP regex to remove EVERYTHING after the colon. the first part can be any length (but it never contains a colon. so in both cases above I'd end up with
foo and anotherfoo
after doing something like this horrendous example of psuedo-code
$string = 'foo:bar';
$newstring = regex_to_remove_everything_after_":"($string);
EDIT
after posting this, would an explode() work reliably enough? Something like
$pieces = explode(':', 'foo:bar')
$newstring = $pieces[0];
explode would do what you're asking for, but you can make it one step by using current.
$beforeColon = current(explode(':', $string));
I would not use a regex here (that involves some work behind the scenes for a relatively simple action), nor would I use strpos with substr (as that would, effectively, be traversing the string twice). Most importantly, this provides the person who reads the code with an immediate, "Ah, yes, that is what the author is trying to do!" instead of, "Wait, what is happening again?"
The only exception to that is if you happen to know that the string is excessively long: I would not explode a 1 Gb file. Instead:
$beforeColon = substr($string, 0, strpos($string,':'));
I also feel substr isn't quite as easy to read: in current(explode you can see the delimiter immediately with no extra function calls and there is only one incident of the variable (which makes it less prone to human errors). Basically I read current(explode as "I am taking the first incident of anything prior to this string" as opposed to substr, which is "I am getting a substring starting at the 0 position and continuing until this string."
Your explode solution does the trick. If you really want to use regexes for some reason, you could simply do this:
$newstring = preg_replace("/(.*?):(.*)/", "$1", $string);
A bit more succinct than other examples:
current(explode(':', $string));
You can use RegEx that m.buettner wrote, but his example returns everything BEFORE ':', if you want everything after ':' just use $2 instead of $1:
$newstring = preg_replace("/(.*?):(.*)/", "$2", $string);
You could use something like the following. demo: http://codepad.org/bUXKN4el
<?php
$s = 'anotherfoo:bar;seg98y34g.?sdebvw h segvu';
$result = array_shift(explode(':', $s));
echo $result;
?>
Why do you want to use a regex?
list($beforeColon) = explode(':', $string);
I am trying to parse a badly formed html table:
A couple of lines of this are:
Food:</b> Yes<b><br>
Pool: </b>Beach<b></b><b><br>
Centre:</b> Yes<b><br>
After spending a lot of time on this with Xpath, I think it is probably better to split the above text into lines use preg_split and parse from there.
The pattern I think would work uses:
<\b><\br>*: <\b>
my code is as follows:
$pattern='</b></br>*:</b>';
$pattern=preg_quote($pattern,'#');
$chars = preg_split($pattern, $output);
print_r($chars);
I am getting the following error:
Delimiter must not be alphanumeric or backslash
What I am doing wrong?
Try this:
$pattern='</b></br>*:</b>';
$pattern=preg_quote($pattern,'#');
$chars = preg_split('#'.$pattern.'#', $output);
print_r($chars);
The preg_quote function just makes it safely escaped, it doesn't actually add the delimiters for you.
As other people will surely point out, using regular expressions is not a good way to parse HTML :)
Your regular expression is also not going to match what you hope. Here's a version that will probably work for your input:
$in = " Pool: </b>Beach<b></b><b><br>";
$out = explode(':', strip_tags($in));
$key = trim($out[0]);
$value = trim($out[1]);
echo "$key = $value\n";
This removes all the HTML, then splits on the colon, and then removes any surrounding whitespace.
Your pattern needs to start and end with a delimiter; looks like you're using # if I'm reading this correctly, so you should have $pattern = '#</b></br>.*:</b>#';.
Also, you're mixing things up; * is not a simple wildcard in regex. If you mean "any number of any characters," the pattern you need is .*. I've included this above.
Given a literal string such as:
Hello\n\n\n\n\n\n\n\n\n\n\n\nWorld
I would like to reduce the repeated \n's to a single \n.
I'm using PHP, and been playing around with a bunch of different regex patterns. So here's a simple example of the code:
$testRegex = '/(\\n){2,}/';
$test = 'Hello\n\n\n\n\n\n\n\n\nWorld';
$test2 = preg_replace($testRegex ,'\n',$test);
echo "<hr/>test regex<hr/>".$test2;
I'm new to PHP, not that new to regex, but it seems '\n' conforms to special rules. I'm still trying to nail those down.
Edit: I've placed the literal code I have in my php file here, if I do str_replace() I can get good things to happen, but that's not a complete solution obviously.
To match a literal \n with regex, your string literal needs four backslashes to produce a string with two backlashes that’s interpreted by the regex engine as an escape for one backslash.
$testRegex = '/(\\\\n){2,}/';
$test = 'Hello\n\n\n\n\n\n\n\n\n\n\n\nWorld';
$test2 = preg_replace($testRegex, '\n', $test);
Perhaps you need to double up the escape in the regular expression?
$pattern = "/\\n+/"
$awesome_string = preg_replace($pattern, "\n", $string);
Edit: Just read your comment on the accepted answer. Doesn't apply, but is still useful.
If you're intending on expanding this logic to include other forms of white-space too:
$output = echo preg_replace('%(\s)*%', '$1', $input);
Reduces all repeated white-space characters to single instances of the matched white-space character.
it indeed conforms to special rules, and you need to add the "multiline"-modifier, m. So your pattern would look like
$pattern = '/(\n)+/m'
which should provide you with the matches. See the doc for all modifiers and their detailed meaning.
Since you're trying to reduce all newlines to one, the pattern above should work with the rest of your code. Good luck!
Try this regular expression:
/[\n]*/
I'm new to preg_replace() and I've been trying to get this to work, I couldn't so StackOverflow is my last chance.
I have a string with a few of these:
('pm_IDHERE', 'NameHere');">
I want it to be replaced with nothing, so it would require 2 wildcards for NameHere and pm_IDHERE.
But I've tried it and failed myself, so could someone give me the right code please, and thanks :)
Update:
You are almost there, you just have to make the replacement an empty string and escape the parenthesis properly, otherwise they will be treated as capture group (which you don't need btw):
$str = preg_replace("#\('pm_.+?', '.*?'\);#si", "", $str);
You probably also don't need the modifiers s and i but that is up to you.
Old answer:
Probably str_replace() is sufficient:
$str = "Some string that contains pm_IDHERE and NameHere";
$str = str_replace(array('pm_IDHERE', 'NameHere'), '', $str);
If this is not what you mean and pm_IDHERE is actually something like pm_1564 then yes, you probably need regular expressions for that. But if NameHere has no actual pattern or structure, you cannot replace it with regular expression.
And you definitely have to explain better what kind of string you have and what kind of string you have want to replace.
OK,I know that I should use a DOM parser, but this is to stub out some code that's a proof of concept for a later feature, so I want to quickly get some functionality on a limited set of test code.
I'm trying to strip the width and height attributes of chunks HTML, in other words, replace
width="number" height="number"
with a blank string.
The function I'm trying to write looks like this at the moment:
function remove_img_dimensions($string,$iphone) {
$pattern = "width=\"[0-9]*\"";
$string = preg_replace($pattern, "", $string);
$pattern = "height=\"[0-9]*\"";
$string = preg_replace($pattern, "", $string);
return $string;
}
But that doesn't work.
How do I make that work?
PHP is unique among the major languages in that, although regexes are specified in the form of string literals like in Python, Java and C#, you also have to use regex delimiters like in Perl, JavaScript and Ruby.
Be aware, too, that you can use single-quotes instead of double-quotes to reduce the need to escape characters like double-quotes and backslashes. It's a good habit to get into, because the escaping rules for double-quoted strings can be surprising.
Finally, you can combine your two replacements into one by means of a simple alternation:
$pattern = '/(width|height)="[0-9]*"/i';
Your pattern needs the start/end pattern character. Like this:
$pattern = "/height=\"[0-9]*\"/";
$string = preg_replace($pattern, "", $string);
"/" is the usual character, but most characters would work ("|pattern|","#pattern#",whatever).
I think you're missing the parentheses (which can be //, || or various other pairs of characters) that need to surround a regular expression in the string. Try changing your $pattern assignments to this form:
$pattern = "/width=\"[0-9]*\"/";
...if you want to be able to do a case-insensitive comparison, add an 'i' at the end of the string, thus:
$pattern = "/width=\"[0-9]*\"/i";
Hope this helps!
David