我怎么能总是从爆炸中返回最后一系列数字

Question

I have a line of code like

$qs = explode('&',$_SERVER['QUERY_STRING']);
$pid = explode('=',$qs[1]);

this will return something such as array(2) { [0]=> string(5) "cPath" [1]=> string(14) "70_229_242_240" }

I then have

$cat_ID = explode('_',$pid[1]);

which returns array(4) { [0]=> string(2) "70" [1]=> string(3) "229" [2]=> string(3) "242" [3]=> string(3) "240" }

Using

print_r($cat_ID[3]);

i can get the final value of 240.

However, this only works in instances where the original string is made up of four numbers separated by underscores. In some circumstances i may have a string of three, two or even one number.

Is there a simple way to make it always fetch the last number in the string without having to code a bunch of if statements to cover situations where $cat_ID[3] or $cat_ID[2] would be empty/non existant?

I suspect the

$pid = explode('=',$qs[1]);

can be changed to take the numbers following the last underscore, but i break it every time i try.

Answer 1

Is there a simple way to make it always fetch the last number in the string without having to code a bunch of if statements to cover situations where $cat_ID[3] or $cat_ID[2] would be empty/non existant?

Sure;

• Explode, like you've done

• Count the number of elements, minus 1 (as it will start at index 0)

  <?php
  $cat_ID = explode('_',$pid[1]);    
  $intLastNumber = $cat_ID[count($cat_ID)-1]
  

Some example code;

<?php
$str = "1_2_3_4_5";
$arrNumbers = explode("_", $str);

echo $arrNumbers[count($arrNumbers)-1]; //Should be 5.

http://codepad.org/HEUSmLkg