In this blog post, we examine how class definitions work in TypeScript:
Table of contents:
This section is a cheat sheet for class definitions in plain JavaScript.
class OtherClass {}
class MyClass1 extends OtherClass {
publicInstanceField = 1;
constructor() {
super();
}
publicPrototypeMethod() {
return 2;
}
}
const inst1 = new MyClass1();
assert.equal(inst1.publicInstanceField, 1);
assert.equal(inst1.publicPrototypeMethod(), 2);
static
class MyClass2 {
static staticPublicField = 1;
static staticPublicMethod() {
return 2;
}
}
assert.equal(MyClass2.staticPublicField, 1);
assert.equal(MyClass2.staticPublicMethod(), 2);
#
(private)class MyClass3 {
#privateField = 1;
#privateMethod() {
return 2;
}
static accessPrivateMembers() {
// Private members can only be accessed from inside class definitions
const inst3 = new MyClass3();
assert.equal(inst3.#privateField, 1);
assert.equal(inst3.#privateMethod(), 2);
}
}
MyClass3.accessPrivateMembers();
#typescript