ios A点到B点返回几条线

这个百度差不多给出来了只是默认取得第一条

#pragma mark - 驾车

- (void)onGetDrivingRouteResult:(BMKRouteSearch*)searcher result:(BMKDrivingRouteResult*)result errorCode:(BMKSearchErrorCode)error
{
    NSArray* array = [NSArray arrayWithArray:_mapView.annotations];
    [_mapView removeAnnotations:array];
    array = [NSArray arrayWithArray:_mapView.overlays];
    [_mapView removeOverlays:array];
    if (error == BMK_SEARCH_NO_ERROR) {
        for (int j = 0;j