Using PHP str_word_count() Function to Count Words in a String

In PHP, the str_word_count() function is used to count the number of words in a string. This article provides a detailed introduction to the function, its syntax, parameters, and several practical code examples.

Function Syntax

<code>str_word_count(string $string [, int $format = 0 [, string $charlist]])</code>

Parameter Description

$string : Required, the input string whose words are to be counted.

$format : Optional, determines the return format; 0 (default) returns the word count, 1 returns an array of words, 2 returns an associative array with word positions as keys.

$charlist : Optional, a list of characters to ignore when counting words; defaults to whitespace and punctuation.

Usage Examples

The following examples illustrate how to use str_word_count() in different scenarios.

Example 1: Count the number of words in a string

<code>$string = "Hello, how are you today?";
$wordCount = str_word_count($string);
echo "Word count: ".$wordCount;
</code>

Output: Word count: 5

Example 2: Return each word as an array

<code>$string = "Hello, how are you today?";
$wordsArray = str_word_count($string, 1);
echo "Word list: ";
foreach ($wordsArray as $word) {
    echo $word." ";
}
</code>

Output: Word list: Hello how are you today

Example 3: Return an associative array with word positions

<code>$string = "Hello, how are you today?";
$wordsArray = str_word_count($string, 2);
echo "Word list: ";
foreach ($wordsArray as $position => $word) {
    echo "Pos".$position.":".$word." ";
}
</code>

Output: Word list: Pos0:Hello Pos6:how Pos10:are Pos14:you Pos18:today

Example 4: Custom ignore character list

<code>$string = "Hello, how are you today?";
$wordCount = str_word_count($string, 0, "o");
echo "Word count: ".$wordCount;
</code>

Output: Word count: 3

Example 5: Use regular expression to match words

<code>$string = "Hello, how are you today?";
preg_match_all('/\w+/', $string, $matches);
echo "Word list: ";
foreach ($matches[0] as $word) {
    echo $word." ";
}
</code>

Output: Word list: Hello how are you today

The str_word_count() function is a simple yet powerful tool for word counting and extraction in PHP, offering flexibility through its parameters and supporting a wide range of string‑processing tasks.