Preg_replace and regex

Question

I have a string like this:

$imgs = "uploads/images/adsense.png|uploads/images/tree-7835_960_720.jpg|uploads/images/way-427984_960_720.jpg|uploads/images/friendship-1081843_960_720.jpg|uploads/images/pinky-swear-329329_960_720.jpg"

I want only the part that refers to the first image:

uploads/imagens/adsense.png

How can I use regex to filter for the content before the first |?

$image = preg_replace(/(*)(\/*)/, $1 ,$imgs)

Either `explode` or `strpos` and `substr`. The latter is a bit faster. — Charlotte Dunois, Mar 23 '16 at 19:01
What is your regex trying to do? Simple regex, `(.*?)\|`. This `(*)` makes no sense though. It is quantifying nothing. — chris85, Mar 23 '16 at 19:05

score 3 · Answer 1 · answered Mar 23 '16 at 19:02

3

Why use regex? You could just do:

substr($imgs, 0, strpos($imgs, '|'));

answered Mar 23 '16 at 19:02

Eihwaz

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Thank´s @Eihwaz your code works well, I only chose the NathanielFord response because it is simpler – Gisele Mar 23 '16 at 19:18
@Gisele We're here to help each other, the important thing is that you've found what you were looking for :) – Eihwaz Mar 23 '16 at 19:22

score 2 · Accepted Answer · answered Mar 23 '16 at 19:03

2

When you have an input value like this:

$imgs = "uploads/images/adsense.png|uploads/images/tree-7835_960_720.jpg|uploads/images/way-427984_960_720.jpg|uploads/images/friendship-1081843_960_720.jpg|uploads/images/pinky-swear-329329_960_720.jpg"

You simply need to explode it, using | as the delimiter:

$images = explode("|", $imgs);

The image you want is the first one:

$images[0];

While you can use regex, there is no particular reason to in this case, and it risks obfuscating what you're doing.

answered Mar 23 '16 at 19:03

Nathaniel Ford

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Could be made more-efficient with the explode limiter argument. `explode('|', $imgs, 1);` – Alexander O'Mara Mar 23 '16 at 19:05
Agreed! `explode("|", $imgs, 1)` would also get the job done, and terminate at the first found string. But there isn't any particular reason to complicate the code unless efficiency is actually at issue. – Nathaniel Ford Mar 23 '16 at 19:06
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@NathanielFord Thank´s it works perfectly – Gisele Mar 23 '16 at 19:13

score 1 · Answer 3 · answered Mar 23 '16 at 19:01

1

/^([^|]*)/

This matches any number of characters from the beginning of the string to the first | character.

answered Mar 23 '16 at 19:01

Mark Evaul

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score 0 · Answer 4 · 2016-03-23T19:03:41.420

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Since you added regex tag.

You can use the positive lookahead like below, along with ^ anchor.

Regex: ^.*?(?=\|)

Regex101 Demo

edited Mar 23 '16 at 19:03

answered Mar 23 '16 at 19:00

I know lookaround assertions are a little inefficient. But it's also a valid solution. Care to explain down vote ? – Mar 23 '16 at 19:09

score 0 · Answer 5 · answered Mar 23 '16 at 19:05

0

use

$upload = explode('|', $imgs);
echo $upload[0];

hope it helps :)

answered Mar 23 '16 at 19:05

FastTurtle

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Preg_replace and regex

5 Answers5