can anyone please explain me..isset() fxn please

Answer 1

isset() is a function that determines if some variables are set (defined) and aren't NULL.
It gets many arguments as you want (infinite arguments; you can also give it just one argument). It returns a boolean that usually use in if statements.

See this:
http://www.sololearn.com/app/php/playground/wFNbzpl9056j/

Answer 2

the function name "is set?" says it all. this function is used to check whether the variable that you are going to use has been set or not. it is good habbit to do.

Answer 3

to determine the variable is define or not. variable with value and $variable = "" will return true

Answer 4

i dont now

Answer 5

hehehe

Answer 6

thank you bro @mohammad_amin_chitgarha :)