如何在PHP中查找字符串中的第一个匹配项？

Question

So basically, I am simply trying to search for a string within a string.

Although, it is a little trickier than that.

I have three small strings, one, two, three

And I have one large string, which is saved as a variable and is quite long.. A few paragraphs long actually.

I need to create a function that allows me to see which string occurs first.

For example, a string like this:

Hello, testing testing one test some more two

Will return one since it occurred before two.

Another example:

Test a paragraph three and testing some more one test test two

Will return three since it occurred before both one and two.

Does anyone have any suggestions or examples on how to do this? Very new to PHP and not to sure how to go about doing this. Thanks!

Answer 1

Try something like this:

$string = 'Hello, testing testing one test some more two';
$words = Array("one", "two", "three");
$low_pos = strlen($string);
$first = '';
foreach($words as $word)
{
    $pos = strpos($string, $word);
    echo "Found ".$word." at ".$pos."<br />";
    if($pos !== false && $pos < $low_pos)
    {
        $low_pos = $pos;
        $first = $word;
    }
}

echo $string."<br />";
echo "FIRST: ".$first;

Output:

Found one at 23
Found two at 42
Found three at 
Hello, testing testing one test some more two
FIRST: one