SBJson库解析（二）NSObject+SBJson
一.NSObject+SBJson.h
1.把objc对象编码成json字符串
通过类别，为NSObject添加新方法：[NSObject JSONRepresentation]
1 @interface NSObject (NSObject_SBJsonWriting)
2 /**
3 虽然定义成NSObject的类别，但仅对NSArray和NSDictionary有效
4 返回：已编码的json对象，或nil
5 */
6 - (NSString *)JSONRepresentation;
7 @end
2.把json对象解析为objc对象
通过类别，为NSString添加新方法：[NSString JSONValue]
1 @interface NSString (NSString_SBJsonParsing)
2 /**
3 返回：NSDictionary或NSArray对象，或nil
4 */
5 - (id)JSONValue;
6 @end
二.NSObject+SBJson.m
导入头文件
1 #import "NSObject+SBJson.h"
2 #import "SBJsonWriter.h"
3 #import "SBJsonParser.h"
1.通过json编写器SBJsonWriter，的stringWithObject: 方法，实现[NSObject JSONRepresentation]编码逻辑
1 @implementation NSObject (NSObject_SBJsonWriting)
2
3 //objc2json
4 - (NSString *)JSONRepresentation {
5 SBJsonWriter *writer = [[SBJsonWriter alloc] init];
6 NSString *json = [writer stringWithObject:self];
7 if (!json)
8 NSLog(@"-JSONRepresentation failed. Error is: %@", writer.error);
9 return json;
10 }
11
12 @end
2.通过json解析器SBJsonParser，的objectWithString: 方法，实现[NSString JSONValue]解析逻辑
1 @implementation NSString (NSString_SBJsonParsing)
2
3 //json2objc
4 - (id)JSONValue {
5 SBJsonParser *parser = [[SBJsonParser alloc] init];
6 id repr = [parser objectWithString:self];
7 if (!repr)
8 NSLog(@"-JSONValue failed. Error is: %@", parser.error);
9 return repr;
10 }
11
12 @end
