c++结构体在ios端解析

定义宏和结构体

#define ENTRYCOUNT 100
#define DATASIZE 256

typedef struct alarm_data_struct
{
    int pos;
    char data[ENTRYCOUNT][DATASIZE];
}stuct_alarm;

将NSString转换char

- (const char *)NSStringToChar:(NSString *)string     //将NSString转化为char
{
    NSStringEncoding enc = CFStringConvertEncodingToNSStringEncoding (kCFStringEncodingGB_18030_2000);
	
	return [string cStringUsingEncoding: enc];
}

读取数据

NSString *fileURL = [NSString stringWithFormat:@"xxx.xxx.xxx数据连接"];
        NSData *date = [NSData dataWithContentsOfURL:[NSURL URLWithString:fileURL]];
        NSString* content = [[NSString alloc] initWithData:date encoding:NSASCIIStringEncoding];
        
        stuct_alarm *stuct_alarm_a;
        const char *cContent = [self NSStringToChar:content];
        stuct_alarm_a = (stuct_alarm *)cContent;
        
        NSLog(@"stucAlarm.pos:%d", stuct_alarm_a->pos);
        for (int i = 0; i < ENTRYCOUNT; i++)
        {
            NSLog(@"i=%d, stuct:%s",i, stuct_alarm_a->data[i]);
        }