JS Review

JS: Core concepts

• Variables: how to declare variables, assign, re-assign, and local vs. global scope.
• Data types: numbers, booleans, strings, arrays, and objects.
• Functions: how to group code into functions, pass arguments to them, and return values from them.
• Conditionals: how to use if/else statements and logical expressions.
• Loops: how to use while and for loops to repeat code.

JS: Variables and Data Types

var myAge = 29;
var myName = "Pamela";
var isSheCool = true;

...what other data types are there?

JS: Functions

var calculateFoodNeeded = function(numDays) {
  return numDays * 3; 
}; 

var makeFunnyName = function(firstName, lastName) {
  return "Miss " + firstName + " Mc" + lastName + "Pants"; 
};

JS: Conditionals

var movieIsActionFlick = true; 
var movieCost = 0; 
if (movieIsActionFlick === true && movieCost < 1) { 
  console.log("Okay fine I'll watch it"); 
} 

var movieHasBradPitt = true; 
var movieHasJohnnyDepp = false; 
if (movieHasBradPitt === true || movieHasJohnnyDepp === true) { 
  console.log( "I'll DEFINITELY watch it");
}

if (movieHasBradPitt) { 
  console.log( "Def watch it" );
} else if (movieCost === 0) { 
  console.log( "Free, might as well"); 
} else if (movieIsActionFlick) {
  console.log("Nah I don't like action flicks"); 
} else { 
  console.log( "I cant decide!"); 
}

JS: Loops

var countdown = 10; 
while (countdown > 0) { 
  console.log(countdown); 
  countdown--; 
} 

var countdown = 10; 
while (countdown > 0) { 
  if (countdown > 1) { 
    console.log(countdown + '...'); 
  } else { 
    console.log(countdown + '!'); 
  } 
  countdown--; 
}

for (var i = 10; i > 0; i--) { 
  console.log(i); 
}
                    

JS: Arrays

var children = ['Oliver', 'Pamela', 'Hunter']; 

console.log('My dad has ' + children.length + ' children'); 
console.log('His first kid was ' + children[0]); 
children.push('Alexis'); 
console.log('His fourth kid was ' + children[3]); 

for (var i = 0; i < children.length; i++) { 
  console.log('Kid #' + (i + 1) + ': ' + children[i]); 
}

JS: Objects

var myCrazyCat = { 
    name: "Angel", 
    age: 3, 
    likes: ["rubber bands", "boxes", "4am petting sessions"], 
    fur: {
        colors: ["orange", "white"], 
        pattern: "striped"
    } 
};

Questions?

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