Php:Difference Between '&&' and 'And'

PHP : Difference between '&&' and 'AND'

They do the same thing, but && has higher precedence than AND.

http://php.net/manual/en/language.operators.precedence.php

Difference between & and && in PHP

& is bitwise AND. See Bitwise Operators. Assuming you do 14 & 7:

    14 = 1110
     7 = 0111
    ---------
14 & 7 = 0110 = 6

&& is logical AND. See Logical Operators. Consider this truth table:

 $a     $b     $a && $b
false  false    false
false  true     false
true   false    false
true   true     true

AND' vs '&&' as operator

If you use AND and OR, you'll eventually get tripped up by something like this:

$this_one = true;
$that = false;

$truthiness = $this_one and $that;

Want to guess what $truthiness equals?

If you said false... bzzzt, sorry, wrong!

$truthiness above has the value true. Why? = has a higher precedence than and. The addition of parentheses to show the implicit order makes this clearer:

($truthiness = $this_one) and $that

If you used && instead of and in the first code example, it would work as expected and be false.

As discussed in the comments below, this also works to get the correct value, as parentheses have higher precedence than =:

$truthiness = ($this_one and $that)

Is there any difference between and and && operators in PHP?

In your case, && and and do the same thing, but take a look at the operator precedence. You can see that && and and are not on the same level, so mixing that could give you unexpected results in some cases - I recommend always using &&, but that's your choice.

Difference between AND [and] &&

On their own, they do exactly the same. So a && b means the same than a and b. But, they are not the same, as && has a higher precedence than and. See the docs for further information.

This example here shows the difference:

// The result of the expression (false && true) is assigned to $e
// Acts like: ($e = (false && true))
$e = false && true;

// The constant false is assigned to $f and then true is ignored
// Acts like: (($f = false) and true)
$f = false and true;

Difference between && and and : Operator precedence and short circuiting

The code

$e = isset($a) and isset($b);

is parsed the same as

($e = isset($a)) and isset($b);

Therefore $e, as determined by isset($a) and the assignment, is true - independent of evaluating isset($b).

PHP operator difference && and and

The reason is operator precedence. Among three operators you used &&, and & =, precedence order is

• &&
• =
• and

So $a in your program calculated as expected but for $b, statement $b = isset($one) was calculated first, giving unexpected result. It can be fixed as follow.

$b = (isset($one) and isset($two));

PHP: OR and ||, AND and &&

There is no difference at all, except that perhaps using AND is somewhat more readable.

EDIT: just checked, and there is a small difference in the operators precedence, see http://php.net/manual/en/language.operators.precedence.php

php operators && vs AND, || vs OR

"||" has a greater precedence than "or"

"&&" has a greater precedence than "and"

From php manual, can read the full article here (Exemple1)

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