PHP. word search?

Question

PHP

Good day.
The problem is this, there is an array of words in which I need to find words with a specific beginning or end. This is what I implemented. Then there was a need for a third parameter - this is a search in the middle of a word, some set of letters. I also managed to do this. But I can't make the last parameter optional.
Here is a loop that iterates over an array of words.

//$viewFile - массив слов
//$starting - начало
//$ending - конец
//$middle - в центре
//$*Chars - количество символов

for ($i = $start ; $i <= $amount && $currentCount < $step; $i++) {
        $str = trim($viewFile[$i]); //обрезаем пробелы
        $haystack = strlen($str);   //считаем количество символов в слове

        if ($str != "" && strcasecmp(substr($str, 0, $startingChars), $starting) == 0 && strcasecmp(mb_substr($str, $haystack - $endingChars), $ending) == 0 && stripos($str, $middle) ) {
            $currentCount++;
            echo '<span class="badge">' . ($currentCount+$curr) . '</span> ';
            echo $viewFile[$i];
            echo '<br>';
        }
    }

In general, this code produces a result only if $middle is given. How to make it so that when $middle = '' the search goes only on the first two parameters?

Answer 1

In general, I got out of the situation like this.

for ($i = $start ; $i <= $amount && $currentCount < $step; $i++) {
        $str = trim($viewFile[$i]); //обрезаем пробелы
        $haystack = strlen($str);   //считаем количество символов в слове

        if ($middleChars != "" ){
            if ($str != "" && strcasecmp(substr($str, 0, $startingChars), $starting) == 0 && strcasecmp(mb_substr($str, $haystack - $endingChars), $ending) == 0 && stripos($str, $middle) )
            {
                $currentCount++;
                echo '<span class="badge">' . ($currentCount+$curr) . '</span> ';
                echo $viewFile[$i];
                echo '<br>';
            }
        }
        else
        {
           if ($str != "" && strcasecmp(substr($str, 0, $startingChars), $starting) == 0 && strcasecmp(mb_substr($str, $haystack - $endingChars), $ending) == 0 )
            {
                $currentCount++;
                echo '<span class="badge">' . ($currentCount+$curr) . '</span> ';
                echo $viewFile[$i];
                echo '<br>';
            } 
        }
    }

Thank you all =)

Answer 2

$b = $str != "" && strcasecmp(substr($str, 0, $startingChars), $starting) == 0 && strcasecmp(mb_substr($str, $haystack - $endingChars), $ending) == 0;
if ($middle != "") $b = $b && stripos($str, $middle);

Answer 3

Why not use regular expressions?
As I understand it, we need a function that is passed five parameters, one of which is optional. Then you can do it like this.

function my_compare($haystack, $needle, $begin, $end, $middle = false) {
    // Используем "ленивую" особенность проверки условий в PHP
    $begin && $regexp[] = "$needle.+";
    $end && $regexp[] = ".+$needle";
    $middle && $regexp[] = ".+$needle.+";

    $result = array();
    foreach $regexp as $pattern {
        $result = array_merge($result, preg_grep($pattern, $haystack));
    }

    return $result;
}

In the case did not check, may contain syntax errors. But I hope I conveyed the idea.