substr_compare
Making this case insensitive is easy for anyone who needs this. Simply convert the haystack and the needle to the same case (upper or lower).
substr_count(strtoupper($haystack), strtoupper($needle))
substr_count
(PHP 4, PHP 5)
substr_count — Count the number of substring occurrences
Description
int substr_count
( string
$haystack
, string $needle
[, int $offset = 0
[, int $length
]] )
substr_count() returns the number of times the
needle substring occurs in the
haystack string. Please note that
needle is case sensitive.
Note:
This function doesn't count overlapped substrings. See the example below!
Parameters
-
haystack -
The string to search in
-
needle -
The substring to search for
-
offset -
The offset where to start counting
-
length -
The maximum length after the specified offset to search for the substring. It outputs a warning if the offset plus the length is greater than the
haystacklength.
Return Values
This function returns an integer.
Changelog
| Version | Description |
|---|---|
| 5.1.0 |
Added the offset and
the length parameters
|
Examples
Example #1 A substr_count() example
<?php
$text = 'This is a test';
echo strlen($text); // 14
echo substr_count($text, 'is'); // 2
// the string is reduced to 's is a test', so it prints 1
echo substr_count($text, 'is', 3);
// the text is reduced to 's i', so it prints 0
echo substr_count($text, 'is', 3, 3);
// generates a warning because 5+10 > 14
echo substr_count($text, 'is', 5, 10);
// prints only 1, because it doesn't count overlapped substrings
$text2 = 'gcdgcdgcd';
echo substr_count($text2, 'gcdgcd');
?>
See Also
- count_chars() - Return information about characters used in a string
- strpos() - Find the position of the first occurrence of a substring in a string
- substr() - Return part of a string
- strstr() - Find the first occurrence of a string
add a note
User Contributed Notes
substr_count - [10 notes]
flobi at flobi dot com ¶
6 years ago
jrhodes at roket-enterprises dot com ¶
4 years ago
It was suggested to use
substr_count ( implode( $haystackArray ), $needle );
instead of the function described previously, however this has one flaw. For example this array:
array (
0 => "mystringth",
1 => "atislong"
);
If you are counting "that", the implode version will return 1, but the function previously described will return 0.
info at fat-fish dot co dot il ¶
6 years ago
a simple version for an array needle (multiply sub-strings):
<?php
function substr_count_array( $haystack, $needle ) {
$count = 0;
foreach ($needle as $substring) {
$count += substr_count( $haystack, $substring);
}
return $count;
}
?>
chrisstocktonaz at gmail dot com ¶
3 years ago
In regards to anyone thinking of using code contributed by zmindster at gmail dot com
Please take careful consideration of possible edge cases with that regex, in example:
$url = 'http://w3.host.tld/path/to/file/..../file.extension';
$url = 'http://w3.host.tld/path/to/file/../file.extension?malicous=....';
This would cause a infinite loop and for example be a possible entry point for a denial of service attack. A correct fix would require additional code, a quick hack would be just adding a additional check, without clarity or performance in mind:
...
$i = 0;
while (substr_count($url, '../') && ++$i < strlen($url))
...
-Chris
XinfoX X at X XkarlX X-X XphilippX X dot X XdeX ¶
9 years ago
Yet another reference to the "cgcgcgcgcgcgc" example posted by "chris at pecoraro dot net":
Your request can be fulfilled with the Perl compatible regular expressions and their lookahead and lookbehind features.
The example
$number_of_full_pattern = preg_match_all('/(cgc)/', "cgcgcgcgcgcgcg", $chunks);
works like the substr_count function. The variable $number_of_full_pattern has the value 3, because the default behavior of Perl compatible regular expressions is to consume the characters of the string subject that were matched by the (sub)pattern. That is, the pointer will be moved to the end of the matched substring.
But we can use the lookahead feature that disables the moving of the pointer:
$number_of_full_pattern = preg_match_all('/(cg(?=c))/', "cgcgcgcgcgcgcg", $chunks);
In this case the variable $number_of_full_pattern has the value 6.
Firstly a string "cg" will be matched and the pointer will be moved to the end of this string. Then the regular expression looks ahead whether a 'c' can be matched. Despite of the occurence of the character 'c' the pointer is not moved.
gigi at phpmycoder dot com ¶
4 years ago
below was suggested a function for substr_count'ing an array, yet for a simpler procedure, use the following:
<?php
substr_count ( implode( $haystackArray ), $needle );
?>
danjr33 at gmail dot com ¶
5 years ago
I ran into trouble using this function when I moved a script from a server with PHP5 to a server with only PHP4.
As the last two parameters were added with 5.1.0, I wrote a substitute function:
<?php
function substr_count5($str,$search,$offset,$len) {
return substr_count(substr($str,$offset,$len),$search);
}
?>
Use it exactly as substr_count() is used in PHP5. (This will work in PHP5 as well.)
Douglas Dennis ¶
2 months ago
It was previously noted that if you use "substr_count(implode(array))" with this array:
array (
0 => "mystringth",
1 => "atislong"
);
The following would result:
"If you are counting "that", the implode version will return 1, but the function previously described will return 0."
You can fix this by using substr_count(implode(' ', array), 'that') which will result in the following string: "mystringth atislong".
Anonymous ¶
4 years ago
It should be noted that unlike the other substr functions, the offset value cannot be a negative value.
<?php
echo substr_count('abcdefg', 'efg', 4, 3); // 1
echo substr_count('abcdefg', 'efg', -3, 3); // warning
?>
zmindster at gmail dot com ¶
4 years ago
For some who seeked for an easy way to resolve URL composed of /../ like http://w3.host.tld/path/to/the/file/../../file.extension, here is a solution
<?php
$url = 'http://w3.host.tld/path/to/file/../file.extension';
while (substr_count($url, "../"))
{
$url = preg_replace('#/[^/]+/\.\.#', '', $url);
}
//outputs 'http://w3.host.tld/path/to/file.extension'
?>
and seems to work perfectly!