UITextFiled 和UITextView 限定长度和判断输入表情

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原创最新推荐文章于 2026-07-31 16:18:20 发布 326 阅读 AI 写同款· GEO 优化 ›

iOS——判断UITextField/UITextView输入的字符中是否含有系统表情在做iOS客户端开发的过程中，有可能有这样的需求：对一条内容进行评论（可是输入的评论内容中可能含有系统表情），将评论内容提交给服务器。当输入的评论内容中含有系统表情的时候不能向服务器提交这条评论，或者评论后app直接给崩掉了，这是让人不可容忍的，因此要排查输入的内容是否含有系统表情，以便给使用者给出提示。下面给出输入的字符中是否含有系统表情的写法。 //"判定"控件的touchUpInsid 阅读详情

001 UITextView 限定长度

_noteStr就是开发者自己要控制的TextView

- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text{
    
    if ([NSString stringContainsEmoji:text]) {
        text = [NSString filterEmoji:text];
        return NO;
    }
    
    if (_noteStr.text.length > 50) {
        [SVProgressHUD showInfoWithStatus:@"最多输入50字符"];
        _noteStr.text = [textView.text substringToIndex:50];
      
    }
    _limitNumLab.text = [NSString stringWithFormat:@"%ld/50",textView.text.length];
    
    return YES;
}

002 UITextFiled 限定长度

-(void)textFieldDidChange :(UITextField *)theTextField{
    
if (theTextField.text.length >1) {
        theTextField.text = [toBeString substringToIndex:1];
   }
}

003 判断输入😊

- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text{
    
    if ([NSString stringContainsEmoji:text]) {
        text = [NSString filterEmoji:text];
        return NO;
    }

    
    return YES;
}

+ (BOOL)stringContainsEmoji:(NSString *)string{
    __block BOOL returnValue = NO;
    
    [string enumerateSubstringsInRange:NSMakeRange(0, string.length) options:NSStringEnumerationByComposedCharacterSequences usingBlock:^(NSString * _Nullable substring, NSRange substringRange, NSRange enclosingRange, BOOL * _Nonnull stop) {
        
        const unichar hs = [substring characterAtIndex:0];
        if (0xd800 <= hs && hs <= 0xdbff){
            if (substring.length > 1){
                const unichar ls = [substring characterAtIndex:1];
                const int uc = (hs - 0xd800) * 0x400 + (ls - 0xdc00) + 0x10000;
                if (0x1d000 <= uc && uc <= 0x1f77f){
                    // 有emoji;
                    returnValue = YES;
                }
            }
        }else if (substring.length > 1){
            const unichar ls = [substring characterAtIndex:1];
            if (ls == 0x20e3){
                // 有emoji
                returnValue = YES;
            }
        }else{
            if (0x2100 <= hs && hs <= 0x27ff){
                returnValue = YES;
            }else if (0x2B05 <= hs && hs <= 0x2b07){
                returnValue = YES;
            }else if (0x2934 <= hs && hs <= 0x2935){
                returnValue = YES;
            }else if (0x3297 <= hs && hs <= 0x3299){
                returnValue = YES;
            }else if (hs == 0xa9 || hs == 0xae || hs == 0x303d || hs == 0x3030 || hs == 0x2b55 || hs == 0x2b1c || hs == 0x2b1b || hs == 0x2b50 ){
                returnValue = YES;
            }else if (hs == 0x200d){
                returnValue = YES;
            }
        }
    }];
    
    return returnValue;
}

+ (NSString *)filterEmoji:(NSString *)string{
    __block NSString *newText = @"";
    
    BOOL isContainsEmoji = [NSString stringContainsEmoji:string];
    if (isContainsEmoji){
        if (string.length == 1){
            newText = [string substringToIndex:string.length - 1];
        }else{
            newText = [string substringToIndex:string.length - 2];
        }
    }else{
        newText = string;
    }
    
    return newText;
}

总结：感谢测试提出的优化点

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