PHP in_array issue while checking zero value in array giving true

Question

I am facing one strange situation while working with PHP's in_array(). Below is my code and its output

<?php
$process = array("as12"=>"deleted","as13"=>1,"as14"=>1);
if(!in_array(0, $process))
    echo "success";
else
    echo "not success";

//It's outputting "not success";

var_dump(in_array(0, $process));
//Output : null

var_dump(in_array(0, $this->tProcessActions) === true);
///Output : true

If we look at the $process array, there is no 0 value in it. Still it's giving me true if I check if(in_array(0, $process))

Can anybody has idea about it?

deceze · Accepted Answer · 2013-06-21 10:12:12Z

4

If you need strict checks, use the $strict option:

in_array(0, $process, true)

PHP's string ⟷ int comparison is well known to be complicated if you don't know the rules/expect the wrong thing.

edited Jun 21, 2013 at 10:12

answered Jun 21, 2013 at 10:07

deceze♦

525k89 gold badges807 silver badges954 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Smile Over a year ago

By putting true last parameter solved an issue. I seen it before long time and forgot to add when there is a mixed values in array like you said string-int

GautamD31 · Accepted Answer · 2013-06-21 10:03:59Z

3

Try like

if(!in_array('0', $process)) {

or you can use search(optional) like

if(array_search('0',$process)) {

answered Jun 21, 2013 at 10:03

GautamD31

28.8k10 gold badges66 silver badges86 bronze badges

2 Comments

Smile Over a year ago

+1 from me. Yes. You're right. But why I need to put 0 in Quotes? If I search for 1 without Quotes then it's giving correct result.

cmbuckley Over a year ago

Because 0 == "deleted" using loose comparison. Note the third parameter to in_array, which forces strict comparison. Also have a look at the type comparison tables.

JunM · Accepted Answer · 2013-06-21 10:05:35Z

2

I believe you should put 0 inside the quotes:

if(!in_array("0", $process))

answered Jun 21, 2013 at 10:05

JunM

7,1608 gold badges40 silver badges60 bronze badges

Comments

DevZer0 · Accepted Answer · 2013-06-21 10:09:15Z

1

I think because in_array maybe not strict type check. because if you check

 if (0 == "deleted") echo "xx";

answered Jun 21, 2013 at 10:09

DevZer0

13.5k7 gold badges29 silver badges54 bronze badges

Comments

Deepak Mallah · Accepted Answer · 2013-06-21 10:09:17Z

1

Try this

if(!in_array('0', $process))

answered Jun 21, 2013 at 10:09

Deepak Mallah

4,0864 gold badges23 silver badges28 bronze badges

Comments

Tim · Accepted Answer · 2013-06-21 10:09:28Z

1

using the strict parameter gives what you want here:

$process = array("as12"=>"deleted","as13"=>1,"as14"=>1);
var_dump( in_array(0, $process, true ) );
// gives false

or use array_search and test if non-false;

var key = array_search( 0, array( 'foo' => 1, 'bar' => 0 ) );
// key is "bar"

edited Jun 21, 2013 at 10:09

answered Jun 21, 2013 at 10:04

Tim

8,7062 gold badges42 silver badges55 bronze badges

Comments

DBuTbKa · Accepted Answer · 2013-06-21 10:10:38Z

1

You need use third parameter [$is_strict] of in_array function.

in_array(0, $process, true)

The point is what any string after (int) conversion equal to 0. (int) "deleted" => 0. So in_array without strict mode is equal to "deleted" == 0 which true. When you use strict its equal to "deleted" === 0 which false.

answered Jun 21, 2013 at 10:10

DBuTbKa

1065 bronze badges

Collectives™ on Stack Overflow

PHP in_array issue while checking zero value in array giving true

7 Answers 7

1 Comment

2 Comments

Comments

Comments

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

7 Answers 7

1 Comment

2 Comments

Comments

Comments

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related