UITextField 限制值输入数字和英文

define kAlphaNum @"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"

<pre name="code" class="objc" style="color: rgb(51, 51, 51); font-size: 14px; line-height: 22.4px;">self.textField.keyboardType = UIKeyboardTypeASCIICapable;

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string{NSCharacterSet *cs;cs = [[NSCharacterSet characterSetWithCharactersInString:kAlphaNum] invertedSet];NSString *filtered = [[string componentsSeparatedByCharactersInSet:cs] componentsJoinedByString:@""]; //按cs分离出数组,数组按@""分离出字符串BOOL canChange = [string isEqualToString:filtered];return self.textField.text.length>=5?NO: canChange;

}

同时能限制长度