iOS开发地图计算两个地点之间的距离

首先我们可以用上面的getLongitudeAndLatitudeWithCity方法获取某一个地点的经纬度。比如我们获取北京和上海的经纬度分别为：北京Longitude = 116.405285，Latitude = 39.904989 上海Longitude = 121.472644， Latitude = 31.231706, 那么北京和上海之间的距离就是：

double distance = [self distanceByLongitude:116.405285 latitude:39.904989 longitude:121.472644 latitude:31.231706];
NSLog(@"Latitude = %f", distance);

- (double)distanceByLongitude:(double)longitude1 latitude:(double)latitude1 longitude:(double)longitude2 latitude:(double)latitude2{
        CLLocation* curLocation = [[CLLocation alloc] initWithLatitude:latitude1 longitude:longitude1];
        CLLocation* otherLocation = [[CLLocation alloc] initWithLatitude:latitude2 longitude:longitude2];
        double distance  = [curLocation distanceFromLocation:otherLocation];//单位是m
        return distance;
    }