JSON具有严格的键/值表示法，用于R4和响应的键/值对不正确。试试这个：
NSString *jsonString = @"{"quizz":[{"id":"1","Q1":"When Mickey was born","R1":"1920","R2":"1965","R3":"1923","R4":"1234","response":"1920"}]}";如果您从文件中读取字符串，则不需要所有的斜杠。
文件将如下所示：
{“ quizz”：[{“ id”：“ 1”，“ Q1”：“米奇出生时”，“ R1”：“ 1920”，“ R2”：“ 1965”，“ R3”：“
1923”， “ R4”：“ 1234”，“响应”：“ 1920”}，{“ id”：“ 1”，“ Q1”：“冷战开始时”，“ R1”：“ 1920”，“
R2”： “ 1965”，“ R3”：“ 1923”，“ R4”：“ 1234”，“响应”：“ 1920”}]}
我用以下代码进行了测试：
NSString *jsonString = @"{"quizz":[{"id":"1","Q1":"When Mickey was born","R1":"1920","R2":"1965","R3":"1923","R4":"1234","response":"1920"}, {"id":"1","Q1":"When start the cold war","R1":"1920","R2":"1965","R3":"1923","R4":"1234","reponse":"1920"}]}";NSLog(@"%@", jsonString);NSError *error = nil;NSDictionary *json = [NSJSonSerialization JSONObjectWithdata:[jsonString dataUsingEncoding:NSUTF8StringEncoding] options:kNilOptions error:&error];NSArray *items = [json valueForKeyPath:@"quizz"];NSEnumerator *enumerator = [items objectEnumerator];NSDictionary* item;while (item = (NSDictionary*)[enumerator nextObject]) { NSLog(@"clientId = %@", [item objectForKey:@"id"]); NSLog(@"clientName = %@",[item objectForKey:@"Q1"]); NSLog(@"job = %@", [item objectForKey:@"Q2"]);}我的印象是，您复制了旧代码，因为您没有使用Apple的序列化和Enumerator而不是Fast
Enumeration。整个枚举内容可以写为
NSArray *items = [json valueForKeyPath:@"quizz"];for (NSDictionary *item in items) { NSLog(@"clientId = %@", [item objectForKey:@"id"]); NSLog(@"clientName = %@",[item objectForKey:@"Q1"]); NSLog(@"job = %@", [item objectForKey:@"Q2"]);}甚至是基于块的枚举的爱好者，如果需要快速安全的枚举，还需要另外一个索引。
NSArray *items = [json valueForKeyPath:@"quizz"];[items enumerateObjectsUsingBlock:^(NSDictionary *item , NSUInteger idx, BOOL *stop) { NSLog(@"clientId = %@", [item objectForKey:@"id"]); NSLog(@"clientName = %@",[item objectForKey:@"Q1"]); NSLog(@"job = %@", [item objectForKey:@"Q2"]);}];
