Asked  8 Months ago    Answers:  5   Viewed   35 times

I'm trying to check if a string starts with http. How can I do this check?

$string1 = 'google.com';
$string2 = 'http://www.google.com';

 Answers

81

PHP 8 or newer:

Use the str_starts_with function:

str_starts_with('http://www.google.com', 'http')

PHP 7 or older:

Use the substr function to return a part of a string.

substr( $string_n, 0, 4 ) === "http"

If you're trying to make sure it's not another protocol. I'd use http:// instead, since https would also match, and other things such as http-protocol.com.

substr( $string_n, 0, 7 ) === "http://"

And in general:

substr($string, 0, strlen($query)) === $query
Wednesday, March 31, 2021
 
RenegadeAndy
answered 8 Months ago
86

You should point to your vendor/autoload.php at Settings | PHP | PHPUnit when using PHPUnit via Composer.

This blog post has all the details (with pictures) to successfully configure IDE for such scenario: http://confluence.jetbrains.com/display/PhpStorm/PHPUnit+Installation+via+Composer+in+PhpStorm

Related usability ticket: http://youtrack.jetbrains.com/issue/WI-18388

P.S. The WI-18388 ticket is already fixed in v8.0

Wednesday, March 31, 2021
 
ojrac
answered 8 Months ago
79

On Mac OS X environment variables available in Terminal and for the normal applications can be different, check the related question for the solution how to make them similar.

Note that this solution will not work on Mountain Lion (10.8).

Saturday, May 29, 2021
 
Nate
answered 5 Months ago
82

Apparently there's no standard C function for this. So:

bool startsWith(const char *pre, const char *str)
{
    size_t lenpre = strlen(pre),
           lenstr = strlen(str);
    return lenstr < lenpre ? false : memcmp(pre, str, lenpre) == 0;
}

Note that the above is nice and clear, but if you're doing it in a tight loop or working with very large strings, it does not offer the best performance, as it scans the full length of both strings up front (strlen). Solutions like wj32's or Christoph's may offer better performance (although this comment about vectorization is beyond my ken of C). Also note Fred Foo's solution which avoids strlen on str (he's right, it's unnecessary if you use strncmp instead of memcmp). Only matters for (very) large strings or repeated use in tight loops, but when it matters, it matters.

Sunday, June 13, 2021
 
Yrtymd
answered 5 Months ago
72

You might check out the substr function in php and grab the first character that way:

http://php.net/manual/en/function.substr.php

if (substr('_abcdef', 0, 1) === '_') { ... }
Sunday, August 8, 2021
 
Shoarc
answered 3 Months ago
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