等待多个异步操作结束，再做汇总操作：
dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
dispatch_group_t group = dispatch_group_create();
dispatch_group_enter(group);
dispatch_group_async(group, queue, ^{
[[HttpRequest sharedRequest] getWithURLString:api_applyListQuery_queryApplySchedule parameters:@{} success:^(id responseObject) {
dispatch_group_leave(group);
} failure:^(NSError *error) {
dispatch_group_leave(group);
}];
});
dispatch_group_enter(group);
dispatch_group_async(group, queue, ^{
[[HttpRequest sharedRequest] getWithURLString:api_applyListQuery_queryApplySchedule parameters:@{} success:^(id responseObject) {
dispatch_group_leave(group);
} failure:^(NSError *error) {
dispatch_group_leave(group);
}];
});
dispatch_group_notify(group, dispatch_get_main_queue(), ^{
// 汇总操作
});
注意：
dispatch_group_enter(group);和 dispatch_group_leave(group); 要一一对应，否则会崩溃
