NSDictionary、NSMutableDictionary相關

NSDictionary

1.NSDictionary 和 json 字符串互轉

1)NSDictionary轉 json 字符串

+ (NSString *)dicToJson:(NSDictionary *)dictionary{
    
    //系統自帶
    
    //    NSError * error;
    
    //    NSData * jsonData = [NSJSONSerialization dataWithJSONObject:dictionary options:kNilOptions error:&error];
    
    //    NSString * jsonStr = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding];
    
    //自定義
    
    NSString *jsonStr = @"{";
    
    NSArray * keys = [dictionary allKeys];
    
    for (NSString * key in keys) {
        
        jsonStr = [NSString stringWithFormat:@"%@\"%@\":\"%@\",",jsonStr,key,[dictionary objectForKey:key]];
        
    }
    
    jsonStr = [NSString stringWithFormat:@"%@%@",[jsonStr substringWithRange:NSMakeRange(0, jsonStr.length-1)],@"}"];
    
    return jsonStr;
    
}

2)json 字符串轉 NSDictionary

+ (NSDictionary *)JsonToDic:(NSString *)jsonString
{
    if (jsonString == nil) {
        return nil;
    }

    NSData *jsonData = [jsonString dataUsingEncoding:NSUTF8StringEncoding];
    NSError *err;
    NSDictionary *dic = [NSJSONSerialization JSONObjectWithData:jsonData
                                                        options:NSJSONReadingMutableContainers
                                                          error:&err];
    if(err)
    {
        NSLog(@"json解析失敗：%@",err);
        return nil;
    }
    return dic;
}

NSMutableDictionary

1.替換值

NSMutableDictionary *newDic = [_dic mutableCopy];

[newDic setObject:_nowRegionArr forKey:@"devices"];

_dic =  newDic;