iOS-百度地图_屏幕所显示范围内的经纬度

　　//当前屏幕中心点的经纬度

    CGFloat centerLongitude = self.mapView.region.center.longitude;

    CGFloat centerLatitude = self.mapView.region.center.latitude;

    //当前屏幕显示范围的经纬度

    CLLocationDegrees pointssLongitudeDelta = self.mapView.region.span.longitudeDelta;

    CLLocationDegrees pointssLatitudeDelta = self.mapView.region.span.latitudeDelta;

    //左上角

    CGFloat leftUpLong = centerLongitude - pointssLongitudeDelta/2.0;

    CGFloat leftUpLati = centerLatitude - pointssLatitudeDelta/2.0;

    //右上角

    CGFloat rightUpLong = centerLongitude + pointssLongitudeDelta/2.0;

    CGFloat rightUpLati = centerLatitude - pointssLatitudeDelta/2.0;

    //左下角

    CGFloat leftDownLong = centerLongitude - pointssLongitudeDelta/2.0;

    CGFloat leftDownlati = centerLatitude + pointssLatitudeDelta/2.0;

    //右下角

    CGFloat rightDownLong = centerLongitude + pointssLongitudeDelta/2.0;

    CGFloat rightDownLati = centerLatitude + pointssLatitudeDelta/2.0;

    NSLog(@"\n 左上   %f,%f---------\n 右上   %f,%f-------\n 左下  %f,%f----- \n 右下  %f,%f",leftUpLong,leftUpLati,rightUpLong,rightUpLati,leftDownLong,leftDownlati,rightDownLong,rightDownLati);

原文：http://www.cnblogs.com/dondre/p/4630677.html