永远订阅循环内的For循环

Question

我有以下代码永久陷入150条记录的循环中。我在这里做错了什么？？

this.getData.getUsers().snapshotChanges().subscribe((usersRes) => {
let c: any = [];
        c = usersRes.map(c => ({ key: c.key, ...c.payload.val() }));
        if (c.length > 0) {
          for (var i = 0; i < c.length; i++) {
            if (c[i].uid != this.afAuth.auth.currentUser.uid) {
              let friend = { $key: c[i].uid, ...c[i] };
              console.log("Inside For: " + i);
              this.addOrUpdateFriend(friend);
            }
          }
        } else {
          this.friends = [];
        }
      });