How can I do a validation to check if a variable is empty and is a string in php

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2

I want to do a denial check and then else the fix. How can I?

Take the example!

<?php

$a = '';


if(!$a && !is_string($a)):
   echo 'False';
else:
   echo 'True';
endif;
php variables
  • 3

    Saul, to check if the variable is empty use the function empty() and to check if it is a string use ìs_string() both returns are boolean.

  • If you do the check $a == '' not enough to know if it’s empty and string?

2 answers

4


Saul, you can also create a function

<?php

function emptyAndString(&$var)
{
    $var = trim($var);
    return empty($var) && is_string($var);
}

$v = 'Valor';
var_dump(emptyAndString($v));
// bool(false) 

$v = '  ';
var_dump(emptyAndString($v));
// bool(false) 

$v = '';
var_dump(emptyAndString($v));
// bool(true)

  • Thank you very much, solved!

4

To leave one more option, the simplest way to do it is like this:

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

With Trim, to make sure nothing goes empty:

if (trim($string) === '') {
}

The operator === checks if the value is identical, that is, compares not only the values, but the types.

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