9

Is it possible to convert null to string with php?

For instance,

$string = null;

to 

$string = "null";
hakre
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Run
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6 Answers6

12

in PHP 7 you can use Null coalescing operator ??

$string = $string ?? 'null';
Erenor Paz
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Omar
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12

Am I missing something here?

if ($string === null) {
    $string = 'null';
}

was thinking something shorter...

You can do it in one line, and omit the braces:

if ($string === null) $string = 'null';

You can also use the conditional operator:

$string = ($string === null) ? 'null' : $string;

Your call.

Community
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Matt Ball
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  • no u didn't. i just thought there might be a way without using if condition... guess not :-) – Run Mar 28 '12 at 18:33
  • What's the problem with using `if`? – Matt Ball Mar 28 '12 at 18:34
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    i think use case for this is only $str = "ergergegE".($string === null ? "null" : $string)."ergegrregege"; it very long string:) $str= "regregrege".json_encode($string)."ergegergerge"; is shortest and universally – user1303559 Dec 28 '12 at 22:23
11

var_export can represent any variable in parseable string.

dev-null-dweller
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2

While not very elegant or legible, you can also do the following

is_null($string) && $string = 'null';  // assignment, not a '==' comparison

// $string is 'null'

or 

$string = is_null($string) ? gettype($string) : $string;

// $string is 'NULL'

Note: var_export($string, true) (mentioned in other replies) returns 'NULL'

dvvrt
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0
if ($string === null)
{
  $string = "null";
}
Oleksi
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    Won't do what is wanted, if the string is empty `''`, because PHP's `==` operator considers `null` to be equal to an empty string. This is why the accepted answer uses `===` operator instead. See [PHP type comparison tables](https://www.php.net/manual/en/types.comparisons.php), scroll down to the table labeled "Loose comparisons with ==". – ToolmakerSteve Aug 22 '19 at 22:01
-1

it has best solution:

$var = null;
$stringNull = json_encode($var);
$null = json_decode($stringNull, true);
var_dump($stringNull);
var_dump($null);
user1303559
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