Check if Variable is Empty - Angular 2

Question

How can one check if a variable is empty in Angular 2? I know that there are native ways such as

if (myVar === null) {do stuff}

but I am looking for something like Angular 1 had such as

if (angular.isEmpty(variable)) { do stuff }.

Q How do check if variable is empty using Angular 2?

Answer 1

Lets say we have a variable called x, as below:

var x;

following statement is valid,

x = 10;
x = "a";
x = 0;
x = undefined;
x = null;

1. Number:

x = 10;
if(x){
//True
}

and for x = undefined or x = 0 (be careful here)

if(x){
 //False
}

2. String x = null , x = undefined or x = ""

if(x){
  //False
}

3 Boolean x = false and x = undefined,

if(x){
  //False
}

By keeping above in mind we can easily check, whether variable is empty, null, 0 or undefined in Angular js. Angular js doest provide separate API to check variable values emptiness.

Answer 2

if( myVariable ) 
{ 
    //mayVariable is not : 
    //null 
    //undefined 
    //NaN 
    //empty string ("") 
    //0 
    //false 
}