JSFiddle - React, Tailwind, and code Playground

JavaScript

class MyClass {
    #somePrivateMethod() {
        return true;
    }
    
    somePublicMethod() {
        return true;
    }
    
    existPrivateMethod(name) {
    		return typeof this[`#${name}`] === "function"; // not work
    }
    
    existPublicMethod(name) {
    		return typeof this[name] === "function";
    }
}

let myClass = new MyClass();
console.log(
	myClass.existPublicMethod('somePublicMethod'), 
	myClass.existPrivateMethod('somePrivateMethod')
);