If else example:
Const age = 20;
If(age){
Console.log(“this value is true”);
}
else{
Console.log(“this value is false”);
}
If the value is 0, “” , undefined, null, NaN, false. This is value is false.
Null vs undefined
The undefined value is not set. If the variable doesn't declare. value is undefined.
An undefined value is set.
For example:
Const name: null;
Double equal (==) or triple equal (===)
Double equal checking this value.
Triple equal checking value and type.
javaScript Function Scope
In javaScript there are two types :
· Local scope
· Globale scope
Variables declared within a javaScript function, become local to the function.
function myFunction() {
var carName = “Volvo”;
// code here
}
A variable declared outside a function becomes global.
var carName = “Volvo”;
// code here
function myFunction() {
// code here
}
