Checking If Then statements in PHP

Question

When I write an if statement, I have it check a variable like so:

if(isset($_GET['username']){
 echo "set";
 } else {
 echo "unset";
}

How could I get my if statement to check if two variables are set similiar to this:

if(isset($_GET['username'] & $_GET['firstname'])){
 echo "set";
 } else {
 echo "unset";
}

So basically how do I check two things in an if statement at once?

Answer 1

if (isset($_GET['username']) AND isset($_GET['firstname']))
{
    echo "set";
}
else
{
    echo "unset";
}

Answer 2

Check out the PHP Manual on control structures and logical operators:

if(isset($_GET['username']) && isset($_GET['firstname'])) {
    echo "set";
} else {
    echo "unset";
}

Using the single & is doing a bitwise operation, which is most certainly not what you want.

and is also a synonym to the && syntax, as the other answers have shown.

EDIT: As pointed out in the comments, you can check if two variables are isset by passing them both to the isset function. However, if you ever wanted to do some other sort of operation you would need to do the logical operators above.

Answer 3

if (isset($_GET['username']) && isset($_GET['firstname']))
{ 
    echo "set"; 
} 
else 
{ 
    echo "unset"; 
}

For reference: PHP's operators

Answer 4

Try using the && operator (logical and) rather than & (binary and)

so if isset returns true for both then the if returns true otherwise the if will return false.

Answer 5

if ( isset($_GET['username']) && isset($_GET['firstname']) )

Answer 6

yes, or

echo ( (isset($_GET['username']) && isset($_GET['firstname'])) ? "set" : "unset" );

Answer 7

if ( isset($_GET['username'], $_GET['firstname']) ) {
    echo 'Set!';
}

isset takes multiple arguments and if multiple parameters are supplied then isset() will return TRUE only if all of the parameters are set. Evaluation goes from left to right and stops as soon as an unset variable is encountered.