需求 ：iOS UITextfield 只允许输入数字 粘贴板如果有除数字之外的字符全部过滤掉，只允许数字上屏显示
- 设置键盘样式 keyboardtype = UIKeyboardTypeASCIICapableNumberPad;
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
if ([self validateIncludeInt:string]) {
NSScanner *scanner = [NSScanner scannerWithString:string];
[scanner scanUpToCharactersFromSet:[NSCharacterSet decimalDigitCharacterSet] intoString:nil];
int number;
[scanner scanInt:&number];
NSString *stringNumber = [NSString stringWithFormat:@"%d",number];
[textField replaceRange:textField.selectedTextRange withText:stringNumber];
}
return [string isEqualToString:@""];
}
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
- (BOOL)validateIncludeInt:(NSString *)stringInput {
NSScanner *scanner = [NSScanner scannerWithString:stringInput];
[scanner scanUpToCharactersFromSet:[NSCharacterSet decimalDigitCharacterSet] intoString:nil];
int number;
return [scanner scanInt:&number];
} - (BOOL)validateOnlyChinese:(NSString *)stringInput {
BOOL result = NO;
NSString *match = @"(^[\u4e00-\u9fa5]+$)";
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF matches %@",match];
result = [predicate evaluateWithObject:stringInput];
return result;
} - (BOOL)validateIncludeChinese:(NSString *)stringInput {
BOOL result = NO;
for(int i=0; i< [stringInput length];i++) {
int a = [stringInput characterAtIndex:i];
if( a > 0x4e00 && a < 0x9fff){
result = YES;
}
}
return result;
}
