Find last character in a string in PHP

问题:

I'm doing some url rewriting in PHP and need to find URLS with a slash at the end and then do a 301 redirect. I thought there'd be a simple PHP function to find last string, but I couldn't find anything. First instincts make m think I need to use regex, but I'm not 100%.

Here's one example:

http://domainx.com/characters/ I want to find a trailing slash and turn it into http://domainx.com/characters

So what function will help me check if the last character is a "/"?

回答1:

A nice solution to remove safely the last / is to use

$string = rtrim($string, '/');

rtrim() removes all /s on the right side of the string when there is one or more.

You can also safely add exactly one single / at the end of an URL:

$string = rtrim($string, '/').'/';

回答2:

You can use substr:

substr($str, -1)

This returns the last byte/character in a single-byte string. See also the multi-byte string variant mb_substr.

But if you just want to remove any trailing slashes, rtrim is probably the best solution.

And since you’re working with URLs, you might also take a look at parse_url to parse URLs as a trailing slash does not need to be part of the URL path.

回答3:

$string[strlen($string)-1] gives you the last character.

But if you want to strip trailing slashes, you can do $string = rtrim($string, '/');. If there is no trailing slash, $string will remain unchanged.

回答4:

You can use basename()

This will return characters for http://domainx.com/characters/ as well as http://domainx.com/characters

You can do like this:-

$page = $_SERVER['REQUEST_URI'];
$module = basename($page);

Then you can use the $module directly in your conditional logic without doing any redirects.

If you want to collect the last / trimmed URL then you can do this:-

If you are storing the project base url in a config file:-

BASE_URL  = 'http://example.com'

then you can do this:-

$page = $_SERVER['REQUEST_URI'];
$module = basename($page);
$trimmedUrl = BASE_URL.'/'.$module;

回答5:

You could preg_replace() a / at the end of the subject

$url = 'http://domainx.com/characters/';
$url = preg_replace('/(?:\/)$/', '', $url);

回答6:

If you have php > 7.1

$string[-1]

Will give you the last character

http://sandbox.onlinephpfunctions.com/code/ff439889f14906749e4eb6328796c354c60f269b