Angular Design Patterns

Singleton

Another handy pattern to use for frontend applications is the singleton. The singleton ensures that only one instance of a given object exists in your program. Moreover, it provides a global point of access to the object.

Here's what it looks like in practice:

export class MySingleton{ 
     
    //The constructor is private so we  
    //can't do `let singleton:MySingleton = new MySingleton();` 
    private static instance:MySingleton = null; 
 
    private constructor(){ 
 
    } 
 
    public static getInstance():MySingleton{ 
        if(MySingleton.instance == null){ 
            MySingleton.instance = new MySingleton(); 
        }

        return MySingleton.instance; 
    } } 
 let singleton:MySingleton = MySingleton.getInstance();

We have a class that has a private static instance:MySingleton attribute. Then, ...