[php]substr_count---在一定范围内统计要查找的字符串在另一字符串出现的次数

<?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 subtrings
$text2 = 'gcdgcdgcd';
echo substr_count($text2, 'gcdgcd');
?>