Question

在我的Xcode项目中，我只是在邮件被取消但是我收到错误（Switch Case在受保护的范围内）时才尝试在邮件用户界面关闭后显示警告显示所有以＆＃34; case＆＃34;。

开头的行

typedef enum MFMailComposeResult MFMailComposeResult;
switch (result)
{
    case MFMailComposeResultCancelled:
            [self dismissViewControllerAnimated:YES completion:NULL];
        UIAlertView *theAlert = [[UIAlertView alloc] initWithTitle:@"Report Sent"
                                                           message:@"Your report has been sent and it will be reviewed. If you are in an emergency, remember to call 911."
                                                          delegate:self
                                                 cancelButtonTitle:@"OK"
                                                 otherButtonTitles:nil];
        [theAlert show];

        NSLog(@"Mail cancelled");
        break;
    case MFMailComposeResultSaved:
        NSLog(@"Mail saved");
        break;
    case MFMailComposeResultSent:

        NSLog(@"Mail sent");
        break;
    case MFMailComposeResultFailed:
        NSLog(@"Mail sent failure: %@", [error localizedDescription]);
        break;
    default:
        break;
}

Answer 1

在多行情况下放置括号

switch (result)
{
    case MFMailComposeResultCancelled: {
        [self dismissViewControllerAnimated:YES completion:NULL];
        UIAlertView *theAlert = [[UIAlertView alloc] initWithTitle:@"Report Sent"
                                                           message:@"Your report has been sent and it will be reviewed. If you are in an emergency, remember to call 911."
                                                          delegate:self
                                                 cancelButtonTitle:@"OK"
                                                 otherButtonTitles:nil];
        [theAlert show];

        NSLog(@"Mail cancelled");
    }
        break;
    case MFMailComposeResultSaved:
        NSLog(@"Mail saved");
        break;
    case MFMailComposeResultSent:

        NSLog(@"Mail sent");
        break;
    case MFMailComposeResultFailed:
        break;
    default:
        break;
}

Answer 2

试试这个

typedef enum MFMailComposeResult MFMailComposeResult;
    switch (result)
    {
        case MFMailComposeResultCancelled:
    {
                [self dismissViewControllerAnimated:YES completion:NULL];
            UIAlertView *theAlert = [[UIAlertView alloc] initWithTitle:@"Report Sent"
                                                               message:@"Your report has been sent and it will be reviewed. If you are in an emergency, remember to call 911."
                                                              delegate:self
                                                     cancelButtonTitle:@"OK"
                                                     otherButtonTitles:nil];
            [theAlert show];

            NSLog(@"Mail cancelled");
            break;
    }
        case MFMailComposeResultSaved:
    {
            NSLog(@"Mail saved");
            break;
    }
        case MFMailComposeResultSent:
    {

            NSLog(@"Mail sent");
            break;
    }
        case MFMailComposeResultFailed:
    {
            NSLog(@"Mail sent failure: %@", [error localizedDescription]);
            break;
    }
        default:
            break;
    }

Switch Case在受保护的范围内

2 个答案: