Ios 如何在用户编辑UITEXTFIELD时自动插入字符串

我希望我的uitextfield在键入结束时类似于XXX.XXX.XXX/XX

为了限制长度，我使用以下方法：

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string  {
    if (textField == _cpfField) {

        NSUInteger newLength = [textField.text length] + [string length] - range.length;
        NSCharacterSet *cs = [[NSCharacterSet characterSetWithCharactersInString:NUMBERS_ONLY] invertedSet];
        NSString *filtered = [[string componentsSeparatedByCharactersInSet:cs] componentsJoinedByString:@""];
        return (([string isEqualToString:filtered])&&(newLength <= CHARACTER_LIMIT));
    } 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{
if（textField==\u cpfField）{
NSUInteger newLength=[textField.text length]+[string length]-range.length；
NSCharacterSet*cs=[[NSCharacterSet characterSetWithCharactersInString:仅限数字]逆变器集]；
NSString*筛选=[[string componentsSeparatedByCharactersInSet:cs]componentsJoinedByString:@”“]；
返回（[string isEqualToString:filtered]）&&（newLength
-（BOOL）textField:（UITextField*）textField shouldChangeCharactersInRange:（NSRange）range replacementString:（NSString*）string{
NSString*text=textField.text；
text=[text stringByReplacingCharactersInRange:range with string:string]；
text=[text stringByReplacingOccurrencesOfString:@.“with string:@]”；
//你在这里检查长度吗
NSMutableString*mutableText=[text mutableCopy]；
//每四个字符将是一个字符。
对于（i=3；i
以下代码应执行以下操作：

限制可键入/粘贴到文本字段中的字符数
在适当的位置自动添加句点和斜杠
防止用户复制/粘贴已具有必需句点/斜杠的字符串时出现问题
也就是说，几乎可以肯定有更有效的方法来实现这一点；但是如果您不关心代码长度，那么它就可以很好地实现这一点

- (BOOL) textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
    NSString *text = textField.text;

    // If we're trying to add more than the max amount of characters, don't allow it
    if ([text length] == 14 && range.location > 13) {
          return NO; 
    }

    // First lets add the whole string we're going for
    text = [text stringByReplacingCharactersInRange:range withString:string];

    // Now remove spaces, periods, and slashes (since we'll add these automatically in a minute)
    text = [text stringByReplacingOccurrencesOfString:@" " withString:@""];
    text = [text stringByReplacingOccurrencesOfString:@"." withString:@""];
    text = [text stringByReplacingOccurrencesOfString:@"/" withString:@""];

    // We need to use an NSMutableString to do insertString calls in a moment
    NSMutableString *mutableText = [text mutableCopy];

    // Every 4th char will be a '.', but we don't want to check more than the first 8 characters
    for (NSUInteger i = 3; i < mutableText.length && i < 8; i += 4) {
        [mutableText insertString:@"." atIndex:i];
    }
    // If the text is more than 11 characters, we also want to insert a '/' at the 11th character index
    if (mutableText.length > 11) {
        [mutableText insertString:@"/" atIndex:11];
    }

    // lets set text to our new string
    text = mutableText;

    // Now, lets check if we need to cut off extra characters (like if the person pasted a too-long string)
    if (text.length > 14) {
        text = [text stringByReplacingCharactersInRange:NSMakeRange(14, mutableText.length-14) withString:@""];
    }

    // Finally, set the textfield to our newly modified string!
    textField.text = text;

    return NO;
}

-（BOOL）textField:（UITextField*）textField应更改字符范围：（NSRange）范围替换字符串：（NSString*）字符串{
NSString*text=textField.text；
//如果我们试图添加超过最大字符数的字符，则不允许添加
如果（[text length]==14&&range.location>13）{
返回否；
}
//首先，让我们添加整个字符串
text=[text stringByReplacingCharactersInRange:range with string:string]；
//现在删除空格、句点和斜杠（因为我们将在一分钟内自动添加它们）
text=[text stringByReplacingOccurrencesOfString:@“with string:@]”；
text=[text stringByReplacingOccurrencesOfString:@.“with string:@]”；
text=[text stringByReplacingOccurrencesOfString:@”/“with string:@”“”；
//我们需要使用一个NSMutableString来立即执行insertString调用
NSMutableString*mutableText=[text mutableCopy]；
//每4个字符将是一个“.”，但我们不希望检查超过前8个字符
对于（i=3；i11）{
[mutableText-insertString:@/“atIndex:11]；
}
//让我们将文本设置为新字符串
文本=可变文本；
//现在，让我们检查是否需要删除额外的字符（例如，如果用户粘贴的字符串太长）
如果（text.length>14）{
text=[text stringByReplacingCharactersInRange:NSMakeRange（14，可变文本.length-14），带字符串：@”“；
}
//最后，将textfield设置为我们新修改的字符串！
textField.text=文本；
返回否；
}

英国国家保险号码文本字段

-（BOOL）textField:（UITextField*）textField应更改字符范围：（NSRange）范围替换字符串：（NSString*）字符串
{
如果（textField==\u txtNationalInsuranceNumber）{
NSString*text=textField.text；
//如果我们试图添加超过最大字符数的字符，则不允许添加
如果（[text length]==13&&range.location>12）{
返回否；
}
//首先，让我们添加整个字符串
text=[text stringByReplacingCharactersInRange:range with string:string]；
//现在删除空格、句点和斜杠（因为我们将在一分钟内自动添加它们）
text=[text stringByReplacingOccurrencesOfString:@“with string:@]”；
//我们需要使用一个NSMutableString来立即执行insertString调用
NSMutableString*mutableText=[text mutableCopy]；
//每4个字符将是一个“.”，但我们不希望检查超过前8个字符
对于（i=2；i11）{
[mutableText insertString:@“atIndex:11]；
}
//让我们将文本设置为新字符串
文本=可变文本；
//现在，让我们检查是否需要删除额外的字符（例如，如果用户粘贴的字符串太长）
如果（text.length>14）{
text=[text stringByReplacingCharactersInRange:NSMakeRange（14，可变文本.length-14），带字符串：@”“；
}
//最后，将textfield设置为我们新修改的字符串！
textField.text=文本；
返回否；
}
其他的
{
返回YES；
}
}
你的解决方案不起作用，它会不断添加点，你也不能使用退格。你知道你可以自己思考吗？这是给你一个方向，而不是给你一个完整的解决方案。在第4行，我有一个空格，而不是一个点（现在已编辑），现在它按预期工作：每4个字符是一个点。在我提供的帮助下，您应该能够真正理解这一点，以获得完整的解决方案。Danilo的解决方案，虽然已损坏（至少最初是这样），但不符合所有要求，但并不是
- (BOOL) textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
    NSString *text = textField.text;

    // If we're trying to add more than the max amount of characters, don't allow it
    if ([text length] == 14 && range.location > 13) {
          return NO; 
    }

    // First lets add the whole string we're going for
    text = [text stringByReplacingCharactersInRange:range withString:string];

    // Now remove spaces, periods, and slashes (since we'll add these automatically in a minute)
    text = [text stringByReplacingOccurrencesOfString:@" " withString:@""];
    text = [text stringByReplacingOccurrencesOfString:@"." withString:@""];
    text = [text stringByReplacingOccurrencesOfString:@"/" withString:@""];

    // We need to use an NSMutableString to do insertString calls in a moment
    NSMutableString *mutableText = [text mutableCopy];

    // Every 4th char will be a '.', but we don't want to check more than the first 8 characters
    for (NSUInteger i = 3; i < mutableText.length && i < 8; i += 4) {
        [mutableText insertString:@"." atIndex:i];
    }
    // If the text is more than 11 characters, we also want to insert a '/' at the 11th character index
    if (mutableText.length > 11) {
        [mutableText insertString:@"/" atIndex:11];
    }

    // lets set text to our new string
    text = mutableText;

    // Now, lets check if we need to cut off extra characters (like if the person pasted a too-long string)
    if (text.length > 14) {
        text = [text stringByReplacingCharactersInRange:NSMakeRange(14, mutableText.length-14) withString:@""];
    }

    // Finally, set the textfield to our newly modified string!
    textField.text = text;

    return NO;
}

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
    if (textField == _txtNationalInsuranceNumber) {
        NSString *text = textField.text;

        // If we're trying to add more than the max amount of characters, don't allow it
        if ([text length] == 13 && range.location > 12) {
            return NO;
        }

        // First lets add the whole string we're going for
        text = [text stringByReplacingCharactersInRange:range withString:string];

        // Now remove spaces, periods, and slashes (since we'll add these automatically in a minute)
        text = [text stringByReplacingOccurrencesOfString:@" " withString:@""];


        // We need to use an NSMutableString to do insertString calls in a moment
        NSMutableString *mutableText = [text mutableCopy];

        // Every 4th char will be a '.', but we don't want to check more than the first 8 characters
        for (NSUInteger i = 2; i < mutableText.length && i < 10; i += 3) {
            [mutableText insertString:@" " atIndex:i];
        }
        // If the text is more than 11 characters, we also want to insert a '/' at the 11th character index
        if (mutableText.length > 11) {
            [mutableText insertString:@" " atIndex:11];
        }

        // lets set text to our new string
        text = mutableText;

        // Now, lets check if we need to cut off extra characters (like if the person pasted a too-long string)
        if (text.length > 14) {
            text = [text stringByReplacingCharactersInRange:NSMakeRange(14, mutableText.length-14) withString:@""];
        }

        // Finally, set the textfield to our newly modified string!
        textField.text = text;

        return NO;
    }
    else
    {
        return  YES;
    }


}