elementAt
ReactiveX:
emit only item n emitted by an Observable
只发送你选定的那个元素
Observable<Int>.from([1, 2, 3, 4, 5])
.elementAt(1)
.subscribe(onNext: { element in
print("element: ", element)
}, onError: { error in
print("error:", error)
})
.disposed(by: bag)
输出:
element: 2
如果elementAt(10)
将会打印error: Argument out of range.