一 前言

本章主要介绍地理编码及反地理编码，需要用到CLGeocoder类

二 地理编码

在下图绿框内输入地址，点击地理编码，显示经度和纬度

#import "ViewController.h"
#import <CoreLocation/CoreLocation.h>

@interface ViewController ()
@property (weak, nonatomic) IBOutlet UITextView *addressTV;// 那个绿框textView
@property (weak, nonatomic) IBOutlet UITextField *longTF;//经度的field
@property (weak, nonatomic) IBOutlet UITextField *laTF;//纬度的field
//地理编码
@property (nonatomic, strong) CLGeocoder *geoC;
@end

@implementation ViewController

#pragma mark - 懒加载
- (CLGeocoder *)geoC{
    if (!_geoC) {
        _geoC = [[CLGeocoder alloc] init];
    }
    
    return _geoC;
}

//点击“地理编码”按钮
- (IBAction)geoCode {
    
    NSString *str = self.addressTV.text;
    
    if ([str length] == 0) {
        return ;
    }
    
    
//    编码其实是去向苹果服务器请求数据
    [self.geoC geocodeAddressString:str completionHandler:^(NSArray<CLPlacemark *> * _Nullable placemarks, NSError * _Nullable error) {
        
        /**
         * CLPlacemark
         *
         */
        
        if (!error) {
            NSLog(@"%@",placemarks);
//            遍历一下这个数组，因为可能有多个查询结果被返回
            [placemarks enumerateObjectsUsingBlock:^(CLPlacemark * _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
                NSLog(@"name = %@",obj.name);
                self.addressTV.text = obj.name;
//                self.laTF.text = [NSString stringWithFormat:@"%f",obj.location.coordinate.latitude];
//                self.longTF.text = [NSString stringWithFormat:@"%f",obj.location.coordinate.longitude];
                self.laTF.text = @(obj.location.coordinate.latitude).stringValue;//获obj.location.coordinate.latitude的字符串格式
                self.longTF.text = @(obj.location.coordinate.longitude).stringValue;
                
            }];
            
        }else{
            NSLog(@"error = %@",error);
        }
    }];
}

- (void)touchesMoved:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
    [self.view endEditing:YES];
}

@end

三 反地理编码

在上图输入经度和纬度的地方，分别输入经度和纬度，点击反地理编码，在绿框内显示地址

//点击“反地理编码”按钮
- (IBAction)reverseGeoCode {
    
    CLLocationDegrees latitude = [self.laTF.text doubleValue];
    CLLocationDegrees longtitude = [self.longTF.text doubleValue];
    
//    TODO： 容错，防止用户输入非经纬度的内容
    
//    if (!) {
//        <#statements#>
//    }
    
    CLLocation *location = [[CLLocation alloc] initWithLatitude:latitude longitude:longtitude];
    [self.geoC reverseGeocodeLocation:location completionHandler:^(NSArray<CLPlacemark *> * _Nullable placemarks, NSError * _Nullable error) {
        
        if (!error) {
            
            NSLog(@"%@",placemarks);
            [placemarks enumerateObjectsUsingBlock:^(CLPlacemark * _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
                self.addressTV.text = obj.name;
            }];
            
            
        }else{
            NSLog(@"无法正常编码");
        }
        
        
    }];
    
}