How can I check whether only one out of three variables is not empty?

Question

I have three variables:

$var1
$var2
$var3

I'm actually looking for the best way to check if only one of these three variables is not empty and the two others are empty.

Is that possible to do this with one if only? If not, then what's the best way?

The variables all contain text.

Answer 1

You can convert variable into array and exclude empty variables using array_filter(). Then use count() after the filter.

if(count(array_filter(array($var1,$var2,$var3)))==1){
  //only 1 variable is not empty
}

Check Fiddle link

Answer 2

Booleans return 0 and 1 with array_sum()

if (array_sum(array(empty($var1), empty($var2), empty($var3))) == 1)
{
    echo "one is empty" ;
}

ETA: This is a simpler way:

if (!empty($var1) + !empty($var2) + !empty($var3) == 1) {
    echo "1 is not empty" ;
}

ETA 2: We don't need the negative signs

if (empty($var1) + empty($var2) + empty($var3) == 2) {
    echo "1 is not empty" ;
}