iphone 地图 根据地址获取经纬度(转)

 http://www.haogongju.net/art/1317722

方法一 

//
//  MapHelper.m
//  JiaoTong
//
//  Created by MOL on 11-6-17.
//  Copyright 2011 MOL. All rights reserved.
//

#import "MapHelper.h"

#import "JSON.h"

@implementation MapHelper

+ (CLLocationCoordinate2D)getPostion:(NSString *)address
{
    NSString *googleURL = [NSString stringWithFormat:@"http://maps.google.com/maps/api/geocode/json?address=%@&sensor=true",
                           [address stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];

    CLLocationCoordinate2D position;
    position.latitude = 0.0;
    position.longitude = 0.0;

    NSError *error;
    NSString *retstr = [NSString stringWithContentsOfURL:[NSURL URLWithString:googleURL] encoding:NSUTF8StringEncoding error:&error];
    if (retstr)
    {
//        NSLog(@"retstr: %@", retstr);
        NSDictionary *dict = [retstr JSONValue];
        if (dict)
        {
            NSArray *results = [dict objectForKey:@"results"];
            if (results && results.count > 0)
            {
                NSDictionary *geometry = [[results objectAtIndex:0] objectForKey:@"geometry"];
                NSDictionary *location = [geometry objectForKey:@"location"];
                position.latitude = [[location objectForKey:@"lat"] doubleValue];
                position.longitude = [[location objectForKey:@"lng"] doubleValue];                
            }
        }
    }
    else
    {
        NSLog(@"error: %@", error);
    }

    return position;
}

@end

方法二  根据地址查经纬度

NSString*address = @"tokyo";
 
   //查詢經緯度
    NSString*output = @"csv";
    NSString*key = @"YouKey";
    NSString*urlStr = [NSStringstringWithFormat:@"http://maps.google.com/maps/geo?q=%@&output=%@&key=%@",address,output,key];
   
    NSURL *url =[NSURL URLWithString:urlStr];


    NSString*retstr = [NSString stringWithContentsOfURL:urlencoding:NSUTF8StringEncoding error:nil];

    NSArray*resultArray = [retstr componentsSeparatedByString:@","];
   
    doublelatitude = [[resultArray objectAtIndex:2] doubleValue];
    doublelongitude = [[resultArray objectAtIndex:3] doubleValue];