下面是一个Switch / Case语句,当无法发送电子邮件时显示错误消息.在大多数情况下,一切似乎都是正确的,但是当我将UIAlertView放入Switch语句时,我在
Xcode中收到错误：
switch (result) {
case MFMailComposeResultCancelled:
NSLog(@"Result: Mail sending canceled");
break;
case MFMailComposeResultFailed:
NSLog(@"Result: Mail sending Failed");
UIAlertView *message = [[UIAlertView alloc] initWithTitle:@"Sending Failed"
message:@"The email Could not be sent."
delegate:nil
cancelButtonTitle:@"OK"
otherButtonTitles:nil];
[message show];
break;
default:
NSLog(@"Result: Mail not sent");
break;
}
为什么在将代码放入案例时会产生错误？
解决方法
把它放在括号中：
case MFMailComposeResultFailed: {
NSLog(@"Result: Mail sending Failed");
UIAlertView *message = [[UIAlertView alloc] initWithTitle:@"Sending Failed"
message:@"The email Could not be sent."
delegate:nil
cancelButtonTitle:@"OK"
otherButtonTitles:nil];
[message show];
break;
}