JavaScript static Method

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Static methods in JavaScript is a way for providing class level methods. To declare a static method, we have to use static keyword as prefix with method name.
Syntax:

class className(){
   static methodName(){
      //method body
   }
}

Ways to call static methods

1. Using Class name

ClassName.methodName();

2. On the constructor property of the class

this.constructor.methodName();

Points to remember:

  • Static keyword is used as prefix with method name to declare a static method.
  • We can call static method without instantiating the class.
  • We can declare more than one static method in a class but if these have a similar name then JavaScript engine always invokes the last one.
  • The static method are commonly used to create utility functions for an application.
  • this keyword can be used to call a static method within another static method but we this keyword can not be used directly to call a static method within the non-static method. For these situations we either have to use the class name or as the property of the constructor like this.constructor.methodName().

Example:

<!DOCTYPE html>
<html>
<body>
<script>
class CollegeName
{
constructor()
{
this.college="NC College";
}
}
class Student extends CollegeName{
constructor(rollNo,name) {
super();
this.rollNo=rollNo;
this.name=name;
}
}
var stu= new Student(1,"Sue");
document.writeln(stu.rollNo+" "+stu.name+" "+stu.college);
</script>
</body>
</html>