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PHP PHP Arrays and Control Structures PHP Conditionals School's Out

Heriberto Nieves
Heriberto Nieves
856 Points
Posted by Heriberto Nieves
Heriberto Nieves
856 Points

what does the ! means if its before a variable?

i don't know what the ! represent before the variable, does it check somethings?

example: if ( !$variable1 || !$variable2 ) { echo 'text goes here'; }

im guessing it checks if the variable is empty? thanks

2 Answers

Steven Parker
Steven Parker
231,198 Points
Steven Parker
Steven Parker
231,198 Points

That's the logical "not" operator. It means "the opposite of". So if the variable contains "false", then putting "!" in front will make the result "true".

Andres Vidoza
Andres Vidoza
9,805 Points
Andres Vidoza
Andres Vidoza
9,805 Points

This actually checks that the string is empty?

Steven Parker
Steven Parker
231,198 Points
Steven Parker
Steven Parker
231,198 Points

The "not" operator just inverts the value. An empty string by itself is considered to be "falsey", and one with content is considered "truthy".