问为什么使用Try/Catch而不是测试NSError

EN

- (void)viewDidLoad
{
    [super viewDidLoad];

    // Instantiate OrtcClient
    ortcClient = [OrtcClient OrtcClientWithConfig:self];

    // Post permissions
    @try {
        NSMutableDictionary* myPermissions = [[NSMutableDictionary alloc] init];

        [myPermissions setObject:@"w" forKey:@"channel1"];
        [myPermissions setObject:@"w" forKey:@"channel2"];
        [myPermissions setObject:@"r" forKey:@"channelread"];

        BOOL result = [ortcClient saveAuthentication:@"http://ortc-developers.realtime.co/server/2.1/" isCLuster:YES authenticationToken:@"myAuthenticationToken" authenticationTokenIsPrivate:NO applicationKey:@"myApplicationKey" timeToLive:1800 privateKey:@"myPrivateKey" permissions:myPermissions];

        if (result) {
            // Permissions correctly posted
        }
        else {
            // Unable to post permissions
        }
    }
    @catch (NSException* exception) {
        // Exception posting permissions
    }

    // Set connection properties
    [ortcClient setConnectionMetadata:@"clientConnMeta"];
    [ortcClient setClusterUrl:@"http://ortc-developers.realtime.co/server/2.1/"];

    // Connect
    [ortcClient connect:@"myApplicationKey" authenticationToken:@"myAuthenticationToken"];
}

NSError *error = nil;
id result = [NSJSONSerialization JSONObjectWithData:jsonData options:NSJSONReadingMutableContainers error:&error];

if (error == nil){
    NSLog(@"%@", result);
}else{
    NSLog(@"%@", [error localizedDescription]);
}