how to access constructor properties from a setInterval on angular2

Question

It seems that i cant access the constructor properties from an setInterval and i need to get and to modify the properties . any help on how can i solve this ?

startit() {
    console.log(this.page,this.nrpages) //works
    setInterval(function() {
        console.log(this.currentPage,this.nrpages) // undefined undefined

Answer 1

Use arrow function

startit() {
  console.log(this.page,this.nrpages) //works
  setInterval(() => {
      console.log(this.currentPage,this.nrpages);
  }); 

Answer 2

The key point here is that this points to the current execution context. So inside setInterval function this is not referring to your outer execution context. You can do something like:

startit() {
    console.log(this.page,this.nrpages) //works
    var thiObj = this;
    setInterval(function() {
        console.log(thisObj.currentPage,thisObj.nrpages) //works