Solved

Using strpos to find first occurence but not working for some reason

Posted on 2016-10-05
5
43 Views
Last Modified: 2016-10-05
HI,
can you see what I'm doing wrong? I am expecting given the code below to have category_id echo out '16' based on strpos finding 'Sport Utility'.

<?php


$trim_style = "Sport Utility";

$category_aliases = array(
  "Sport Utility" => 16,
  "4dr Car" => 17,
  "HB" => 21,
  "Hbk" => 21,
  "2dr Car" => 19,
  "Convertible" => 20,
  "Truck\nPickup\nRegular Cab Pickup - Short Bed\nRegular Cab Pickup - Long Bed\nCrew Cab Pickup - Short Bed\nCrew Cab Pickup - Long Bed" => 15,
  "Station Wagon" => 13
);


$category_id = false;

		foreach ($category_aliases as $alias => $id) {
			if(strpos($trim_style, $alias))
			{
				$category_id = $id;
			}
		}
		
	echo $category_id;


?>

Open in new window

0
Comment
Question by:tjyoung
5 Comments
 
LVL 109

Accepted Solution

by:
Ray Paseur earned 500 total points
ID: 41830079
PHP strpos() may return zero, which is loosely interpreted as FALSE in the context of the if() statement.  Check the man page.  You may want to change the test to use an identicality for !False (not false).
https://iconoun.com/demo/temp_tjyoung.php
<?php // demo/temp_tjyoung.php
/**
 * https://www.experts-exchange.com/questions/28974502/Using-strpos-to-find-first-occurence-but-not-working-for-some-reason.html
 *
 * http://php.net/manual/en/function.strpos.php
 */
error_reporting(E_ALL);

$trim_style = "Sport Utility";

$category_aliases = array(
  "Sport Utility" => 16,
  "4dr Car" => 17,
  "HB" => 21,
  "Hbk" => 21,
  "2dr Car" => 19,
  "Convertible" => 20,
  "Truck\nPickup\nRegular Cab Pickup - Short Bed\nRegular Cab Pickup - Long Bed\nCrew Cab Pickup - Short Bed\nCrew Cab Pickup - Long Bed" => 15,
  "Station Wagon" => 13
);


$category_id = false;

foreach ($category_aliases as $alias => $id) {
    if(FALSE !== strpos($trim_style, $alias)) {
        $category_id = $id;
    }
}

echo $category_id;

Open in new window

Outputs:
16

Open in new window

0
 
LVL 1

Author Closing Comment

by:tjyoung
ID: 41830096
Yep that was totally it.
Thanks again for the direction.
0
 
LVL 42

Expert Comment

by:zephyr_hex (Megan)
ID: 41830098
You need to qualify your condition, such as:

if(strpos($trim_style, $alias) > -1)

Open in new window


or

if(strpos($trim_style, $alias) !== FALSE)

Open in new window

0
 
LVL 54

Expert Comment

by:Julian Hansen
ID: 41830099
Ray has answered this but to elaborate
$trim_style = "Sport Utility";

$category_aliases = array(
  "Sport Utility" => 16,

Open in new window

If you compare the two strings Sport Utility is found at position 0 of the first element of the array (arrays and strings being 0 indexed)

So strpos is going to return a 0 for the comparison which means I found one at position 0 - NOT I did not find one.

Change to (as Ray suggests)
if(strpos($trim_style, $alias) !== false)

Open in new window

And it should work.
!== means the returned value must be the value false - not a falsy value (Null, empty, 0, false)
0
 
LVL 42

Expert Comment

by:zephyr_hex (Megan)
ID: 41830101
oops.... a second late to the party ;)
0

Featured Post

Gigs: Get Your Project Delivered by an Expert

Select from freelancers specializing in everything from database administration to programming, who have proven themselves as experts in their field. Hire the best, collaborate easily, pay securely and get projects done right.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Generating table dynamically is the most common issue faced by php developers.... So it seems there is a need of an article that explains the basic concept of generating tables dynamically. It just requires a basic knowledge of html and little maths…
These days socially coordinated efforts have turned into a critical requirement for enterprises.
Explain concepts important to validation of email addresses with regular expressions. Applies to most languages/tools that uses regular expressions. Consider email address RFCs: Look at HTML5 form input element (with type=email) regex pattern: T…
The viewer will learn how to create a basic form using some HTML5 and PHP for later processing. Set up your basic HTML file. Open your form tag and set the method and action attributes.: (CODE) Set up your first few inputs one for the name and …

776 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question