根据经纬度 求距离

在Info.plist中加入两个缺省没有的字段
NSLocationAlwaysUsageDescription
NSLocationWhenInUseUsageDescription

-(void)GetLonAndLat
{
// 2. 调用请求：
if ([[[UIDevice currentDevice] systemVersion] doubleValue] > 8.0)
{
//设置定位权限 仅ios8有意义
[self.locationManager requestWhenInUseAuthorization];// 前台定位

    //  [locationManager requestAlwaysAuthorization];// 前后台同时定位
}


locationManager = [[CLLocationManager alloc] init];    //设置代理

locationManager.delegate = self;
[CLLocationManager locationServicesEnabled];
locationManager.desiredAccuracy=kCLLocationAccuracyThreeKilometers;
[locationManager startUpdatingLocation];

}

-(void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations
{
CLLocation *cl = [locations objectAtIndex:0];
self.loX = [[NSString stringWithFormat:@"%f",cl.coordinate.longitude] doubleValue];
self.LoY = [[NSString stringWithFormat:@"%f",cl.coordinate.latitude] doubleValue];

}
//-(void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation{
// NSLog(@"%f,%f",newLocation.coordinate.latitude,newLocation.coordinate.longitude);
//}
-(void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error{
NSLog(@"%@",error);
}

/**

• 计算距离
• @param lat1 本地距离 纬度
• @param lat2 本地距离 纬度
• @param lng1 其他距离 经度
• @param lng2 其他距离 经度
• @return
  */

+(double)distanceBetweenOrderBy:(double)lat1 :(double)lat2 :(double)lng1 :(double)lng2{
double dd = M_PI/180;
double x1=lat1dd,x2=lat2dd;
double y1=lng1dd,y2=lng2dd;
double R = 6371004;
double distance = (2Rasin(sqrt(2-2cos(x1)cos(x2)cos(y1-y2) - 2sin(x1)sin(x2))/2)) / 1000;
//km 返回
// return distance1000;
NSLog(@"distance距离%f; lat1= %f; lat2 =%f; lng1 = %f; lng2 = %f ",distance,lat1,lat2,lng1,lng2);//一个纬度间距离是111km
//返回 m
return distance;

}