我有一个像json字符串:
{
"a":"val1","b":"val2","c":"val3"
}
我有一个客观的C头文件,如:
@interface TestItem : NSObject @property Nsstring *a; @property Nsstring *b; @property Nsstring *c; @end
我可以解析Json并获取TestItem类的实例吗?
我知道如何将json解析为字典,但我想在一个类中解析它(类似于gson在Java中所做的那样).
解决方法
您不必直接使用字典,而是始终使用键值编码将JSON反序列化(解析)到您的类.键值编码是Cocoa的一个很好的特性,它允许您在运行时按名称访问类的属性和实例变量.正如我所看到的,您的JSON模型并不复杂,您可以轻松应用它.
person.h
#import <Foundation/Foundation.h> @interface Person : NSObject @property Nsstring *personName; @property Nsstring *personMiddleName; @property Nsstring *personLastname; - (instancetype)initWithJSONString:(Nsstring *)JSONString; @end
person.m
#import "Person.h"
@implementation Person
- (instancetype)init
{
self = [super init];
if (self) {
}
return self;
}
- (instancetype)initWithJSONString:(Nsstring *)JSONString
{
self = [super init];
if (self) {
NSError *error = nil;
NSData *JSONData = [JSONString dataUsingEncoding:NSUTF8StringEncoding];
NSDictionary *JSONDictionary = [NSJSONSerialization JSONObjectWithData:JSONData options:0 error:&error];
if (!error && JSONDictionary) {
//Loop method
for (Nsstring* key in JSONDictionary) {
[self setValue:[JSONDictionary valueForKey:key] forKey:key];
}
// Instead of Loop method you can also use:
// thanks @sapi for good catch and warning.
// [self setValuesForKeysWithDictionary:JSONDictionary];
}
}
return self;
}
@end
appDelegate.m
@implementation AppDelegate
- (void)applicationDidFinishLaunching:(NSNotification *)aNotification {
// JSON String
Nsstring *JSONStr = @"{ \"personName\":\"MyName\",\"personMiddleName\":\"MyMiddleName\",\"personLastname\":\"MyLastName\" }";
// Init custom class
Person *person = [[Person alloc] initWithJSONString:JSONStr];
// Here we can print out all of custom object properties.
NSLog(@"%@",person.personName); //Print MyName
NSLog(@"%@",person.personMiddleName); //Print MyMiddleName
NSLog(@"%@",person.personLastname); //Print MyLastName
}
@end
文章using JSON to load Objective-C objects好点开始.