Question

我正在做一个条件语句，检查文本字段是否包含某些字符，如果它是UIAlertView将显示的话。目前，如果文本字段包含字母，则显示警报，如何扩展我的方法以包含诸如？之类的字符？！，$等。

if ([self.withdrawTextField.text rangeOfCharacterFromSet:[NSCharacterSet letterCharacterSet]].location != NSNotFound) {
        UIAlertView * alert = [[UIAlertView alloc] initWithTitle:@"Ooops" message:@"Please only use numbers and the period (.)." delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil, nil];
        [alert show];

}

Answer 1

试试这个：

NSMutableCharacterSet *mcs1 = [[NSCharacterSet letterCharacterSet] mutableCopy];
 [mcs1 addCharactersInString:@"?!.$"];

if ([self.withdrawTextField.text rangeOfCharacterFromSet:mcs1].location != NSNotFound) {
        UIAlertView * alert = [[UIAlertView alloc] initWithTitle:@"Ooops" message:@"Please only use numbers and the period (.)." delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil, nil];
        [alert show];

}

Answer 2

因为你只想在字符串中使用数字和点，而不是在代码下面尝试。它可能对你有帮助。

NSCharacterSet *myCharSet = [NSCharacterSet characterSetWithCharactersInString:@"0123456789."];
for (int i = 0; i < [[self.withdrawTextField.text length]; i++) 
{
    unichar c = [string characterAtIndex:i];

    if (![myCharSet characterIsMember:c]) 
       {
        UIAlertView * alert = [[UIAlertView alloc] initWithTitle:@"Ooops" message:@"Please only use numbers and the period (.)." delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil, nil];
        [alert show];
        return;
       }
}

检查UITextfield是否包含（？！$等）

2 个答案: