Which of the following values evaluate eventually to false?
Respuesta
22
0
'undefined'
!false
Pregunta 2
Pregunta
What does the following code produce as a message?
var numOfChoice = 3;
switch(numOfChoice) {
case 1:
console.log(`You have selected ${numOfChoice}');
break;
case 2:
console.log(`You have selected ${numOfChoice}');
break;
case 3:
console.log(`You have selected ${numOfChoice}');
default:
console.log(`You have selected nothing!');
Respuesta
You have selected 3
You have selected nothing!
error! A break keyword is missing.
You have selected 3
You have selected nothing!
Pregunta 3
Pregunta
When is it appropriate to use a switch-case syntax in favor of if-else statements?
Respuesta
There is no case at all, if else syntax is more precise and less error prone.
When we want to check multiple times if a variable holds a specific value.
In any case. Switch cases provide a better and cleaner syntax to work with.
In case we want to compare a variable if is greater or lower than a specific value.
Pregunta 4
Pregunta
What does the following code produce as a message to console?
var choice = 5;
if (choice == 2) {
console.log(2);
} else {
console.log(choice);
}else if (choice == 5) {
console.log('You have selected 5 pieces');
}
Respuesta
2
You have selected 5 pieces.
The number of your choice.
Syntax error.
Pregunta 5
Pregunta
Imagine we are having 10 numbers from 1 to 10. 1, 2, 3, 4, 5, 6, 7, ,8 ,9, 10.
For everyone of these numbers we run the following statement:
if (num % 2 !== 0 ) {
// Do something here
}
Under which numbers will this condition be executed?
Respuesta
none
all
2, 4, 6, 8, 10
1, 3, 5, 7, 9
Pregunta 6
Pregunta
Given that we have these variables:
var money = 2;
var drink = 5;
var inMood = true;
var freeTime = true;
if (money - drink > 0 || !inMood && freetime) {
console.log('Go out for a drink');
} else {
console.log('Stay in');
}
Will i go for a drink or what?
Respuesta
Of course i do. Party animal rules.
Nope. Misery at it's best.
Pregunta 7
Pregunta
What is the outcome of this statement?
var playFootball = true;
!playFootball ? console.log('I told you, you can't play today!') : console.log('Play freely without fear');
Respuesta
I told you, you can't play today!
Play freely without fear
Pregunta 8
Pregunta
Select one of the following statements that is wrong.
Respuesta
In if else statements, it is a good practice to check the more unique condition first and then the more general.
There is no limit to how many 'if else' statements we can put as alternatives to an if block.
Default option is mandatory inside a switch case block.
'Else' statement is mandatory as alternative to an 'if' block.