Last important lesson

Introduction to IF...THEN...ELSE

IF you want to do things in programming you need to learn a little logic. Not much! But IF you are going to eat ice-cream you are going to want to open your mouth first.

Basic logic operators in javascript (IF):

• && and
• || or
• ! not
• == equals
• != not-equals
• ({}) Braces (do this first)

A Short Example

if ((youPickYouNose && youEatIt) || (!youBrushYourTeeth)) {
    alert("you'll get sick")
} else {
    alert("you'll stay healthy")
}
if (true == false) {
    alert('hi')
}if (true != false) {
    alert('hi')
}

Try it out

Try changing the following false/true values below to see what happens.

function willIGetSick() {
  let youPickYourNose = false;
  let youEatIt = false;
  let youBrushYourTeeth = true;
  let outcome = ""; //this is an empty string (we call letters strings)
  if ((youPickYourNose && youEatIt) || (!youBrushYourTeeth)) {
      outcome = "you'll get sick";
  } else {
      outcome = "you'll stay healthy";
  }
  return <p style={{color:"navy", textDecoration:"underline", textAlign:"center"}}>{outcome}</p>
}
function willIGetSick() {
  let youPickYourNose = false;
  let youEatIt = false;
  let youBrushYourTeeth = true;
  let outcome = ""; //this is an empty string (we call letters strings)
  if ((youPickYourNose && youEatIt) || (!youBrushYourTeeth)) {
      outcome = "you'll get sick";
  } else {
      outcome = "you'll stay healthy";
  }
  return <p style={{color:"navy", textDecoration:"underline", textAlign:"center"}}>{outcome}</p>
}

A Real Example

Notice why the circle is only coming up in the bottom-right corner? It's the IF. Don't forget to click play.