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phpstrpos

why can i not find a substring with strpos()?


I'd like to extract a substring within a string but seems like strpos() doesn't fidn my substring. I have the following code:

<?php
function get_string($string, $start, $end)
{
    $pos = 0;
    echo $string,"<br>-------------------------<br>";
    echo $start;
    $pos = strpos($string, $start);
    echo "<strong>".$pos."</strong>";
    if ($pos === false)
    { // Zero is not exactly equal to false...
        return $pos;
    }
    $pos += strlen($start);
    $len = strpos($string, $end, $pos)-$pos;
    $found = substr($string, $pos, $len);
    return $found;
}

$str='<table class="views-table cols-4"><thead><tr><th class="views-field views-field-line-item-title">
        Title          </th>
<th class="views-field views-field-commerce-unit-price">
        Unit price          </th>
<th class="views-field views-field-quantity">
        Quantity          </th>
<th class="views-field views-field-commerce-total views-align-right">
        Total          </th>
</tr></thead><tbody><tr class="odd views-row-first views-row-last"><td class="views-field views-field-line-item-title">
         "Sweet Heart" Package    (SPA02)          </td>
<td class="views-field views-field-commerce-unit-price">
        135.00  CAD          </td>
<td class="views-field views-field-quantity">
        1          </td>
<td class="views-field views-field-commerce-total views-align-right">
 135.00  CAD          </td>
</tr></tbody></table>';

 $str=strtr($str,array("<"=>"&lt;","&"=>"&amp;"));
 echo get_string($str,'class="odd views-row-first views-row-last">&lt;td    class="views-field views-field-line-item-title">','&lt;/td>');
?>

and get this oupt in the browser:

<table class="views-table cols-4"><thead><tr><th class="views-field views-field-line-item-title"> Title </th> <th class="views-field views-field-commerce-unit-price"> Unit price </th> <th class="views-field views-field-quantity"> Quantity </th> <th class="views-field views-field-commerce-total views-align-right"> Total </th> </tr></thead><tbody><tr class="odd views-row-first views-row-last"><td class="views-field views-field-line-item-title"> "Sweet Heart" Package (SPA02) </td> <td class="views-field views-field-commerce-unit-price"> 135.00 CAD </td> <td class="views-field views-field-quantity"> 1 </td> <td class="views-field views-field-commerce-total views-align-right"> 135.00 CAD </td> </tr></tbody></table>
-------------------------
class="odd views-row-first views-row-last"><td class="views-field views-field-line-item-title">

and I woudl expect to see $pos returning a number that is printed in html - why does strpos() nor return the expectd position?

Thanks!


Solution

  • Incorrect Answer

    You have &lt; in your needle string. &lt; is only needed if you encode special html characters for output.

    [Edited]

    Correct Answer

    I should have ran the code before posted the above. The real issue is two many spaces in the needle string

    replace

    echo get_string($str,'class="odd views-row-first views-row-last">&lt;td    class="views-field views-field-line-item-title">','&lt;/td>');
    

    with

    echo get_string($str,'class="odd views-row-first views-row-last">&lt;td class="views-field views-field-line-item-title">','&lt;/td>');