1private firstAction():Promise<any> {
2  return new Promise<any>(
3    (resolve, reject) => { ... }
4  );
5}
6private secondAction():Promise<any> {
7  return new Promise<any>(
8    (resolve, reject) => { ... }
9  );
10}
11execute() {
12  this.firstAction().then(
13    (firstResult:any) => this.secondAction().then(
14      (secondResult:any) => { ... }
15    );
16  )
17}

1new Promise(function(resolve, reject) {
2
3  setTimeout(() => resolve(1), 1000); // (*)
4
5}).then(function(result) { // (**)
6
7  alert(result); // 1
8  return result * 2;
9
10}).then(function(result) { // (***)
11
12  alert(result); // 2
13  return result * 2;
14
15}).then(function(result) {
16
17  alert(result); // 4
18  return result * 2;
19
20});