contains contains：如果发射的数据包含指定值，那就返回true @Testpublic void contains1() {Observable.just(1, 2, 3).contains(1).subscribe(new Consumer<Boolean>() {@Overridepublic void accept(Boolean aBoolean) throws Ex

http://www.xmaspx.com/u/guitarpark/Blog.aspx/t-19 DefaultIfEmpty函数：若指定数据源为空的时候，返回一个默认值，此函数延时加载。例：int[] ints = { 1, 2, 3, 4, 5, 6 };var result = ints.DefaultIfEmpty();foreach (int x in result)R