how can I call a method only one time in a class? (first time when add "new")-CodePudding

I have a long code with a lot method, but since I am on stackoverflow I will add to you a simple minimal example here (is not the final, but I hope show you the bug):

I have a code like this:

class MyClass {
  constructor() {
    this.myMethod();
  }

  myMethod() {
    console.log("hello world!")
  }
}

new MyClass();

and this code is ok.

the method runs once.

but if I call it more than 2 times it will run the method another time.

/* other code  */
new MyClass();
new MyClass();
new MyClass();
new MyClass();
new MyClass();

// wrong output:
hello world
hello world 
hello world
...

// desired output (only one time)
hello world

if you are interested in why run one time. this is because I want that the class created some Ui elements at the first but then get the generated ui and change the things with the given parameters in constructor

CodePudding user response：

check this documentation: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes/static

there is a keyword for classes that do this thing called static

class MyClass {
  // no () just static and { your code }
  static {
    console.log("called once");
  }

  myOtherMethod() {
    console.log("run when I want or every time")
  }
}

/* other code  */
new MyClass();
new MyClass();
new MyClass();
new MyClass();
new MyClass();