Iphone 验证带有特殊字符的文本字段时，键盘退格按钮不起作用

我尝试用特殊字符验证文本字段

但是，按键盘上的删除按钮。未删除文本字段数据

我用这段代码来验证Textfield

 - (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
      NSCharacterSet * invalidNumberSet = [NSCharacterSet characterSetWithCharactersInString:@"_!@#$%^&*()[]{}'\"<>:;|\\/?+=~`"];

     if([[string stringByTrimmingCharactersInSet:invalidNumberSet]isEqualToString:@""])
     {
        return NO;
     }
     else
     {
        return YES;
     }
}

-（BOOL）textField:（UITextField*）textField应更改字符范围：（NSRange）范围替换字符串：（NSString*）字符串
{
NSCharacterSet*invalidNumberSet=[NSCharacterSet characterSetWithCharactersInString:@“\u！@$%^&*（）[]{}\\”：；\ 124;\\/？+=``]；
if（[[string stringByTrimmingCharactersInSet:invalidNumberSet]IseQualString:@”“）
{
返回否；
}
其他的
{
返回YES；
}
}

---

请告诉我该怎么做？

为了防止这些特殊单词，我建议这可能会有所帮助，并且有很多选项可以防止这种类型的字符串匹配，我建议您使用下面的方法之一

   if([string isEqualToString:@"_"] || [string isEqualToString:@"@"] || [string isEqualToString:@"#"] || [string isEqualToString:@"$"] || [string isEqualToString:@"%"] ||  [string isEqualToString:@"^"] ||  [string isEqualToString:@"&"] ||  [string isEqualToString:@"*"] ||  [string isEqualToString:@"("] ||  [string isEqualToString:@")"] ||  [string isEqualToString:@"["] ||  [string isEqualToString:@"]"] ||  [string isEqualToString:@"{"] || [string isEqualToString:@"'"] || [string isEqualToString:@"\""] || [string isEqualToString:@"\\"] || [string isEqualToString:@"<"] || [string isEqualToString:@">"]|| [string isEqualToString:@":"]|| [string isEqualToString:@";"]|| [string isEqualToString:@"|"]|| [string isEqualToString:@"/"]|| [string isEqualToString:@"?"]|| [string isEqualToString:@"+"] || [string isEqualToString:@"="]|| [string isEqualToString:@"~"]  ) {
        return NO;
    }else{
        return YES;
    }

if（[string IseQualtString:@“”]| |[string IseQualtString:@“@”]| |[string IseQualtString:@“#”]|[string IseQualtString:@“$”]|[string IseQualtString:@“%”]|[string IseQualtString:@“^”]|[string IseQualtString:@“&”]|[string IseQualtString:@]（[124;][字符串IseQualtString:@“[”]| |[字符串IseQualtString:@”]|[字符串IseQualtString:@“{”]|[字符串IseQualtString:@”]|[字符串IseQualtString:@“\”]|[字符串IseQualtString:@“\ \ \ \”]|[字符串IseQualtString:@”]|[字符串IseQualtString:@]|[字符串IseQualtString:@]。][字符串IseQualtString:@“/”]| |[字符串IseQualtString:@”？“]| |[字符串IseQualtString:@“+”]| |[字符串IseQualtString:@”=“]| |[字符串IseQualtString:@”~“]{
返回否；
}否则{
返回YES；
}

另一个选择是正则表达式。

---

希望这对您有所帮助。

创建这样的通用函数来实现您的功能

-(BOOL)isNumeric:(NSString *)pTmpString
{
    BOOL isValid = YES;
    NSCharacterSet *myCharSet = [NSCharacterSet characterSetWithCharactersInString:@"_!@#$%^&*()[]{}'\"<>:;|\\/?+=~`"];
    for (int i = 0; i < [pTmpString length]; i++) 
    {
        unichar c = [pTmpString characterAtIndex:i];
        if ([myCharSet characterIsMember:c]) 
            isValid = NO;
    }
    return isValid;
}

这将不接受从键盘到文本字段的特殊字符，尽管您在键盘上按了这些字母

如果你有任何疑问，告诉我我会帮助你的

---

希望这将对您有所帮助。

您是否要阻止这些特殊角色

- (BOOL)textField:(UITextField *)theTextField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string 
{
    BOOL isValid = [self isNumeric:string];    
    return isValid;
}