When I'm calling an overridden method from the base class constructor, I cannot get a value of a sub class property correctly.
Example:
class A
{
constructor()
{
this.MyvirtualMethod();
}
protected MyvirtualMethod(): void
{
}
}
class B extends A
{
private testString: string = "Test String";
public MyvirtualMethod(): void
{
alert(this.testString); // This becomes undefined
}
}
I would like to know how to correctly override functions in typescript.
The key is calling the parent's method using super.methodName();
class A {
// A protected method
protected doStuff()
{
alert("Called from A");
}
// Expose the protected method as a public function
public callDoStuff()
{
this.doStuff();
}
}
class B extends A {
// Override the protected method
protected doStuff()
{
// If we want we can still explicitly call the initial method
super.doStuff();
alert("Called from B");
}
}
var a = new A();
a.callDoStuff(); // Will only alert "Called from A"
var b = new B()
b.callDoStuff(); // Will alert "Called from A" then "Called from B"