php - 我想过滤一个字符串并使用 php 创建一个数组

Question

这是我的示例字符串(这个有五个单词；在实践中，可能会有更多):

$str = "I want to filter it";

我想要的输出:

$output[1] = array("I","want","to","filter","it");
$output[2] = array("I want","want to","to filter","filter it");
$output[3] = array("I want to","want to filter","to filter it");
$output[4] = array("I want to filter","want to filter it");
$output[5] = array("I want to filter it");  

我正在尝试:

$text = trim($str);
$text_exp = explode(' ',$str);
$len = count($text_exp);
$output[$len][] = $text;  // last element
$output[1] = $text_exp;  // first element

这给了我第一个和最后一个数组。如何获取所有中间数组？

Answer 1

适用于任何长度单词的更通用的解决方案:

$output = array();

$terms = explode(' ',$str);
for ($i = 1; $i <= count($terms); $i++ )
{
    $round_output = array();
    for ($j = 0; $j <= count($terms) - $i; $j++)
    {
        $round_output[] = implode(" ", array_slice($terms, $j, $i));
    }
    $output[] = $round_output;
}