PHP: Does a String start with a specific String or Character?

Surely, there are several solutions for this issue. One of this is:

$s = 'www.askingbox.com';

if (strpos($s, 'www') === 0) {
   // $s starts with "www"
}

The function strpos() returns the position of the search string. If the position is 0, the string is beginning with the search string.
2014-02-28 at 20:47

Another possibilty is to use substr() instead. I take the same example:

$s = 'www.askingbox.com';

if (substr($s, 0, 3) === 'www') {
  // $s starts with "www"
}

if (substr($s, 0, 4) === 'http') {
  // $s starts with "http"
}

With substr(), you can cut a part of a string. In the first case from the example above 3 characters starting at the first character and in the second case 4 characters. So, you have to adjust the 3 and 3 to the length of the search string.

Alternatively, you can also write a more general function like this:

if (substr($s, 0, strlen($s) === 'www') {
   // $s starts with "www"
}

In this example, I have replaced the codec length with strlen($s). With this, the required length is determined dynamically.
2014-03-01 at 15:21

You can also have a look at my article about strStart and strEnd functions in PHP.

The strStart function introduced in this article can be used exactly for the purpose of the question.
2014-03-15 at 21:36

And here is just another possibility. This time using strncmp():

$s = 'abcdefgh';
$search = 'abc';

if (strncmp($s, $search, strlen($search)) === 0) {
  // $s starts with $search
}

With strncmp() you are comparing the string passed as first parameter with the string passed as the second parameter. The comparison is done on the length specified in the third parameter.

For equal strings, the result is 0.
2014-03-30 at 00:06