在輸入東西的時候,如果想限制最大字數,可以用下面方法:
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
if ([string isEqualToString:@"/n"]){
return YES;
}
NSString * aString = [textField.text stringByReplacingCharactersInRange:range withString:string];
if (self.searchTextField == textField)
{
if ([aString length] > 5) {
textField.text = [aString substringToIndex:5];
UIAlertView *alert = [[UIAlertView alloc] initWithTitle:nil
message:@"超過最大字數不能輸入了"
delegate:nil
cancelButtonTitle:@"Ok"
otherButtonTitles:nil, nil];
[alert show];
[alert release];
return NO;
}
}
return YES;
}