OBJECTIVE-C Development--geo-coding and geo-coding of map positioning

We usually do map positioning, mainly by latitude and longitude to accurately locate a location.

But, we are human ah, we are not satellites AH.

The user on the map to find a place, we can not tell him, this place is longitude how many degrees, latitude how many degrees.

We're going to have to tell somebody a place name, right?

That's what we're talking about today in geocoding and geo-coding.

Geocoding: You say a place name, such as "West Lake", we give you to return its latitude and longitude, and then you find out the latitude and longitude to locate

Anti-geocoding: I'll tell you a latitude and longitude, and you return the place name by latitude. It's better to stick a pin on the map, and what's called a pin, we'll talk about it later.

First of all, my interface is this kind of paper, that is, two buttons, drag lines, generate two methods

The source code is as follows

//

Viewcontroller.m

demo3_ Anti-geo-coding

//

Created by Shiran on 16/3/23.

copyright©2016 year Shiran. All rights reserved.

//

#import "ViewController.h"

#import <CoreLocation/CoreLocation.h>

@interface viewcontroller ()

geo-coding

@property(nonatomic,strong)clgeocoder *geocoder;

@end

@implementation Viewcontroller

-(clgeocoder *) geocoder{

if (! _geocoder) {

_geocoder=[[clgeocoder alloc]init];

}

return _geocoder;

}

geo-coding

-(ibaction) Geocoder: (UIButton *) Sender {

nsstring *address=@ " West Lake ";

if (address. Length==0) {

return;

    }    

[self. Geocoder geocodeaddressstring: Address completionhandler: ^ (nsarray< Clplacemark *> * _nullable placemarks, nserror * _nullable error) {

if (error==nil) {

for (clplacemark *placemark in placemarks) {

NSLog(@ "%@", Placemark. Addressdictionary[@ "City"]);

NSLog(@ "%f,%f", Placemark. Location. Coordinate. Latitude, Placemark. Location. Coordinate. Longitude);

}

}

Else

{

NSLog(@ "%@", error);

}

}];

}

Anti-geo-coding

-(ibaction) Reversegeocoder: (UIButton *) Sender {

cllocation *loc = [[cllocation alloc]initwithlatitude: longitude: $];

[self. Geocoder reversegeocodelocation: Loc completionhandler: ^ (nsarray<Clplacemark *> * _nullable placemarks, nserror * _nullable error) { /c14>

if (error==nil) {

for (clplacemark *placemark in placemarks) {

NSLog(@ "%@,%@", Placemark. Addressdictionary[@ "City"],placemark. Name);

}

}

    }];  

}

-(void) viewdidload {

[Super viewdidload];

additional setup after loading the view, typically from a nib.

}

-(void) didreceivememorywarning {

[Super didreceivememorywarning];

//Dispose of any resources, can be recreated.

}

@end

Click the Geocoding button, the console output is as follows, because my simulator is in English, so the console printing is also in English, so foreign flavor ^_^

See, Nanchang latitude and longitude and latitude and longitude of Hangzhou have come out, it seems more than Hangzhou has a West lake, Nanchang also has West Lake Ah, long posture Bar ^_^

Click the Anti-geocoding button and the console output is as follows

Here, according to my latitude and longitude to return the address is Beijing Mentougou

OBJECTIVE-C Development--geo-coding and geo-coding of map positioning