javascript is not null

if(data !== null && data !== '') {
   // do something
}if (variable !== null) {
  console.log("Var is NOT null");
}//Even if the value is 0, this will execute. 

if (myVar !== null) {...}

//If you don't want it to execute when it's 0, then set it as

if (myVar) {...}

//This will return false if var value is 0.