Javascript Boolean Lesson p2
A boolean expression is an expression that evaluates to a boolean value. A boolean expression is evaluated using relational and logical operators. The result of a boolean expression is either true or false.
Javasvript Booleans
Introduction
Relational operators in JavaScript are used to compare two values, returning a Boolean value (true or false) based on the relationship. Relational operators are extremley similar to math functions such as less than or equal too.
Relational Operators
These codes determine the true or false
-
== : Equal to, checks if two values are the same (e.g., verifying a password match).
-
!= : Not equal to, checks if two values are different (e.g., ensuring input changes).
-
=== : Strict equal to, checks equality and type (e.g., validating exact user ID).
-
!== : Strict not equal to, checks inequality and type (e.g., ensuring different type or value).
-
> : Greater than, left value is larger than the right (e.g., comparing scores or ages).
-
< : Less than, left value is smaller than the right (e.g., setting age limits).
-
>= : Greater than or equal to, left value is larger or equal (e.g., minimum age validation).
-
<= : Less than or equal to, left value is smaller or equal (e.g., ensuring max quantity in cart).
Example
this is the example of booleans. You can see how booleans works.
```python
%%js
//You can change this booleans. try out more!
let isLoggedIn = true;
let hasAdminAccess = false;
let amal = false;
if (amal) {
console.log("Amal detected. No gummies. Get out.")
}
else {
if (isLoggedIn) {
console.log("Welcome to the site!");
// Check if the user has admin access
if (hasAdminAccess) {
console.log("You have admin access.");
}
else {
console.log("You are logged in, but you don't have admin access.");
}
}
else {
console.log("Please log in to access the site.");
}
}
```
Example: `Boolean(1)`, `Boolean(-100)`
- `False` if the variable is 0.
Example: `Boolean(0)`
If the variable inside of the `Boolean()` is string, then the code following the rule...
- `True` if the variable has something in it.
Example: `Boolean("aaaa")`, `Boolean("0")`
- `False` if the variable doesn't have anything in.
Example: `Boolean("")`
##### Warnings
`Boolean()` and `boolean()` is completely different code. Make sure you put the capital B.
```python
%%js
// Popcorn hack
// Open Devolper Tools
// Help --> Devolper Tools
// Change the variables so you get 4 Correct
let a = "abc";
let b = 0;
let c = -1;
let d = "";
if (Boolean(a) == false) {
console.log("A = Correct");
} else {
console.log("A = InCorrect");
}
if (Boolean(b) != false) {
console.log("B = Correct");
} else {
console.log("B = Incorrect");
}
if (Boolean(c) != true) {
console.log("C = Correct");
} else {
console.log("C = Incorrect");
}
if (Boolean(d) == true) {
console.log("D = Correct");
} else {
console.log("D = incorrect");
}
if (Boolean(a) == false && )
```