In PHP, is
if(!$foo)
equivalent with
if($foo != true)
or with
if($foo !== true)
or is it even something completly different of both?
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Foo Bar
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1all of them are same! – Ronak Patel Dec 05 '14 at 15:52
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a simple run can give you the right answer. – Dec 05 '14 at 15:55
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See also [Reference - What does this symbol mean in PHP?](http://stackoverflow.com/q/3737139) – mario Dec 05 '14 at 16:00
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possible duplicate of [Reference - What does this symbol mean in PHP?](http://stackoverflow.com/questions/3737139/reference-what-does-this-symbol-mean-in-php) – Dec 05 '14 at 16:09
4 Answers
4
Note that,
== OR != compares the values of variables for equality, type casting as necessary. === OR !== checks if the two variables are of the same type AND have the same value.
This answer will give you better explanation of this concept: https://stackoverflow.com/a/80649/3067928
Community
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Ronak Patel
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I'm not asking about the difference between `==` and `===` (or their negations), which I know. I'm asking about their relation to `!`. – Foo Bar Dec 05 '14 at 16:25
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if(!$foo)
is the equivalent to
if($foo != true)
so
$foo = null;
if(!$foo){
echo "asd";
}
will ouptut "asd"
Alexis Peters
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$a != $b
TRUE if $a is not equal to $b after type juggling.
$a !== $b
TRUE if $a is not equal to $b, or they are not of the same type.
See type juggling in PHP for more info on type juggling.
Sources : php.net
Jay S.
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I'm not asking about the difference between `==` and `===` (or their negations), which I know. I'm asking about their relation to `!`. – Foo Bar Dec 05 '14 at 16:27
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Its not the same
!= is No equal (Returns true if is not equal)
!== is Not identical (Returns true if is not equal , or they are not of the same type)
Jelle Keizer
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I'm not asking about the difference between `==` and `===` (or their negations), which I know. I'm asking about their relation to `!`. – Foo Bar Dec 05 '14 at 16:28