xcode4.2.1 中使用 sbjson 的 3.1版本来解析json字符串

1，访问 SBJson的项目官网，并且下载 https://github.com/stig/json-framework/downloads
注意:按照作者的说明，

SBJson v3.1alpha3 - source and API docs for Mac and iOS development, now with ARC support!

只有在3.1的版本上，才支持xcode 4.2中开启ARC的功能。所以我使用这个版本。

2.依然采用源代码编译的方式。把SBJson下载后解开的 目录中的classes目录拖拉到 项目中。

3.在项目的h文件中引入#import "SBJson.h"。不再使用#import "JSON.h"

4.测试用的json字符串是： {"userInfo":{"userName":"徐泽宇","sex":"男"}}

5.测试代码是 ：

//测试json的解析
-(void)testJsonParser: (NSString *) jsonString
{
jsonString = [[NSString alloc] initWithString:@"{\"userInfo\":{\"userName\":\"徐泽宇\",\"sex\":\"男\"}}"];
NSLog(@"正在解析json字符串是：%@",jsonString);

SBJsonParser * parser = [[SBJsonParser alloc] init];
NSError * error = nil;
NSMutableDictionary *jsonDic = [parser objectWithString:jsonString error:&error];
NSMutableDictionary * dicUserInfo = [jsonDic objectForKey:@"userInfo"];

NSLog(@"%@",[jsonDic objectForKey:@"userInfo" ]);
NSLog(@"%@",[dicUserInfo objectForKey:@"userName"]);
NSLog(@"%@",[dicUserInfo objectForKey:@"sex"]);
}

控制台打印的内容如下:

2011-11-29 02:56:04.882 IManager[4040:fb03] {

sex = "\U7537";

userName = "\U5f90\U6cfd\U5b87";

}

2011-11-29 02:56:04.887 IManager[4040:fb03] 徐泽宇

2011-11-29 02:56:04.888 IManager[4040:fb03] 男

注意：这里的json的字符串。一定要用双引号，不能使用单引号。这点上和java的类包是有区别的。这个问题浪费了我1个小时。

处理json对象有多个记录的方法。

json字符串是：

{"customer":[{"name":"roamer","ycount":"232.4","sumcount":"322.3"},{"name":"王三","ycount":"221.2","sumcount":"1123.2"},{"name":"李四","ycount":"1221.2","sumcount":"12123.2"}]}

+(void) test{
DLog(@"test 开始运行");
NSString * customerGridJsonString = [[NSString alloc]initWithString:@"{\"customer\":[{\"name\":\"roamer\",\"ycount\":\"232.4\",\"sumcount\":\"322.3\"},{\"name\":\"王三\",\"ycount\":\"221.2\",\"sumcount\":\"1123.2\"},{\"name\":\"李四\",\"ycount\":\"1221.2\",\"sumcount\":\"12123.2\"}]}"];

SBJsonParser * parser = [[SBJsonParser alloc] init];
DLog(@"%@",customerGridJsonString);
NSError * error = nil;

NSMutableDictionary *root = [[NSMutableDictionary alloc] initWithDictionary:[parser objectWithString:customerGridJsonString error:&error]];
//注意转换代码
SBJsonWriter *jsonWriter = [[SBJsonWriter alloc] init];

NSString *jsonString = [jsonWriter stringWithObject:root];

[jsonWriter release];
DLog(@"%@",jsonString);
//注意转换代码
NSMutableArray * customers = [root objectForKey:@"customer"];
DLog(@"%@",customers);
for(NSMutableDictionary * member  in customers)
{
DLog(@"%@",[[member objectForKey:@"name"] description]);
}

}

控制台输出是:

2012-04-22 13:55:41.845 iQuestionnaire[13464:fb03] test
开始运行
2012-04-22 13:55:41.846 iQuestionnaire[13464:fb03] {"customer":[{"name":"roamer","ycount":"232.4","sumcount":"322.3"},{"name":"王三","ycount":"221.2","sumcount":"1123.2"},{"name":"李四","ycount":"1221.2","sumcount":"12123.2"}]}

2012-04-22 13:55:41.854 iQuestionnaire[13464:fb03] {"customer":[{"sumcount":"322.3","name":"roamer","ycount":"232.4"},{"sumcount":"1123.2","name":"王三","ycount":"221.2"},{"sumcount":"12123.2","name":"李四","ycount":"1221.2"}]}
[
2012-04-22 13:55:41.854 iQuestionnaire[13464:fb03] (
{
name = roamer;
sumcount = "322.3";
ycount = "232.4";
},
{
name = "\U738b\U4e09";
sumcount = "1123.2";
ycount = "221.2";
},
{
name = "\U674e\U56db";
sumcount = "12123.2";
ycount = "1221.2";
}
)

2012-04-22 13:55:41.854 iQuestionnaire[13464:fb03] roamer

2012-04-22 13:55:41.856 iQuestionnaire[13464:fb03]
王三

2012-04-22 13:55:41.856 iQuestionnaire[13464:fb03]
李四

注意这里的转换代码： 如果直接使用
NSMutableDictionary *root 来获得 字符串，将会对json字串产生以下变化
1. 中文问题
2.加入了（）符号
3.所有的： 变成了 =
要避免这个问题的产生，需要用

SBJsonWriter *jsonWriter = [[SBJsonWriter
alloc] init];

NSString *jsonString = [jsonWriter
stringWithObject:root];

[jsonWriter release];

这段代码来把 NSMutableDictionary 转成 NSString