iOS TextFiled,TextView 长度限制，表情限制

野性酷女 2022-01-19 00:59 277阅读 0赞

### 需求：在文本框中限制输入表情，长度限制 ###

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### 实现原理: 通过这两个控件的代理与通知实现 ###

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### 阅读前提: ###

*  由于搜狗等不断改善，可能小部分表情未能限制
 *  原理较为简单，不再讲解

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#### Github: [长度限制，表情限制][Link 1] ####

#### 简书地址 : [iOS TextFiled,TextView 长度限制，表情限制][iOS TextFiled_TextView] ####

#### 博客地址 : [iOS TextFiled,TextView 长度限制，表情限制][iOS TextFiled_TextView 1] ####

#### 掘金地址 : [iOS TextFiled,TextView 长度限制，表情限制][iOS TextFiled_TextView 2] ####

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### 注意 ###

1.  可以根据需求自行更改提示样式等等
2.  可以根据需求自行优化过滤算法
3.  好处：我们只需要有这样一个类，以后项目中所有需要限制的地方仅仅需要直接导入头文件，引用类方法即可

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### 使用方法: ###

#### 1. 导入头文件 ####

#import "XDXTextContentHandler.h"
    复制代码

#### 2. 直接在对应的代理或通知中对用头文件即可 ####

- (void)viewDidLoad {
        [super viewDidLoad];
        // Do any additional setup after loading the view, typically from a nib.
        
        self.testTextFiled.delegate = self;
        self.testTextView.delegate  = self;
        
        [[NSNotificationCenter defaultCenter] addObserver:self
                                                 selector:@selector(textFiledEditChanged:)
                                                     name:@"UITextFieldTextDidChangeNotification"
                                                   object:self.testTextFiled];
    }
    
    
    #pragma mark - Notification
    - (void)textFiledEditChanged:(NSNotification *)obj {
        [XDXTextContentHandler handleTextFiledEditChangedWithNotification:obj textMaxLength:kTitleTextMaxLength isShowTip:YES];
    }
    #pragma mark - Delegate
    
    #pragma mark TextFiled
    - (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
        return [XDXTextContentHandler handleTextFiledShouldChangeTextInRangeWithTextFiled:textField range:range replacementText:string isShowTip:YES];
    }
    
    #pragma mark TextView
    - (void)textViewDidChange:(UITextView *)textView {
        [XDXTextContentHandler handleTextViewDidChangeWithTextView:textView textMaxLength:kTitleTextMaxLength isShowTip:YES];
    }
    
    - (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text {
        return [XDXTextContentHandler handleTextViewShouldChangeTextInRangeWithTextView:textView range:range replacementText:text isShowTip:YES];
    }
    
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### 具体实现: ###

*  长度限制：即检测到超过设定长度后截取字符串
 *  表情限制：检测是苹果自带还是第三方，过滤关键字

@implementation XDXTextContentHandler
    
    #pragma mark - Public Main Func
    
    + (void)handleTextFiledEditChangedWithNotification:(NSNotification *)notification textMaxLength:(int)textMaxLength isShowTip:(BOOL)isShowTip {
        UITextField *textField  = (UITextField *)notification.object;
        if ([textField isFirstResponder]) {
            NSString *toBeString = textField.text;
            if (toBeString.length > textMaxLength) {
                textField.text = [toBeString substringToIndex:textMaxLength];
                
                if (isShowTip) {
                    [self showAlertVCWithTitle:@"Warning" message:[NSString stringWithFormat:@"Text max length is %d",textMaxLength]];
                }
            }
        }
    }
    
    + (void)handleTextViewDidChangeWithTextView:(UITextView *)textView textMaxLength:(int)textMaxLength isShowTip:(BOOL)isShowTip {
        if ([textView isFirstResponder]) {
            if (textView.text.length > textMaxLength) {
                textView.text = [textView.text substringToIndex:textMaxLength];
                if (isShowTip) {
                    [self showAlertVCWithTitle:@"Warning" message:[NSString stringWithFormat:@"Text max length is %d",textMaxLength]];
                }
            }
        }
        
        NSString *toBeString = textView.text;
        
        if (![self isInputRuleAndBlank:toBeString]) {
            textView.text = [self disable_emoji:toBeString];
            
            if (isShowTip) {
                [self showAlertVCWithTitle:@"Warning" message:[NSString stringWithFormat:@"Not input emoji"]];
            }
            return;
        }
        
        NSString *lang = [[textView textInputMode] primaryLanguage]; // 获取当前键盘输入模式
        NSLog(@"%@",lang);
        if([lang isEqualToString:@"zh-Hans"]) { //简体中文输入,第三方输入法（搜狗）所有模式下都会显示“zh-Hans”
            UITextRange *selectedRange = [textView markedTextRange];
            //获取高亮部分
            UITextPosition *position = [textView positionFromPosition:selectedRange.start offset:0];
            //没有高亮选择的字，则对已输入的文字进行字数统计和限制
            if(!position) {
                NSString *getStr = [self getSubString:toBeString textMaxLength:textMaxLength];
                if(getStr && getStr.length > 0) {
                    textView.text = getStr;
                }
            }
        } else{
            NSString *getStr = [self getSubString:toBeString textMaxLength:textMaxLength];
            if(getStr && getStr.length > 0) {
                textView.text= getStr;
            }
        }
    }
    
    + (BOOL)handleTextViewShouldChangeTextInRangeWithTextView:(UITextView *)textView range:(NSRange)range replacementText:(NSString *)text isShowTip:(BOOL)isShowTip {
        if ([textView isFirstResponder]) {
            if ([[[textView textInputMode] primaryLanguage] isEqualToString:@"emoji"] || ![[textView textInputMode] primaryLanguage]) {
                return NO;
            }
            
            //判断键盘是不是九宫格键盘
            if ([self isNineKeyBoard:text]){
                return YES;
            }else{
                if ([self hasEmoji:text] || [self stringContainsEmoji:text]){
                    if (isShowTip) {
                        [self showAlertVCWithTitle:@"Warning" message:[NSString stringWithFormat:@"Not input emoji"]];
                    }
                    return NO;
                }
            }
        }
        return YES;
    }
    
    + (BOOL)handleTextFiledShouldChangeTextInRangeWithTextFiled:(UITextField *)textFiled range:(NSRange)range replacementText:(NSString *)text isShowTip:(BOOL)isShowTip {
        if ([textFiled isFirstResponder]) {
            if ([[[textFiled textInputMode] primaryLanguage] isEqualToString:@"emoji"] || ![[textFiled textInputMode] primaryLanguage]) {
                if (isShowTip) {
                    [self showAlertVCWithTitle:@"Warning" message:[NSString stringWithFormat:@"Not input emoji"]];
                }
                return NO;
            }
            
            //判断键盘是不是九宫格键盘
            if ([self isNineKeyBoard:text]){
                return YES;
            }else{
                if ([self hasEmoji:text] || [self stringContainsEmoji:text]){
                    if (isShowTip) {
                        [self showAlertVCWithTitle:@"Warning" message:[NSString stringWithFormat:@"Not input emoji"]];
                    }
                    return NO;
                }
            }
        }
        return YES;
    }
    
    #pragma mark - Private
    #pragma mark TextView禁止表情相关
    // 字母、数字、中文常用字符正则判断（不包括空格）
    + (BOOL)isInputRuleNotBlank:(NSString *)str {
        NSString *pattern = @"^[a-zA-Z,.!@#$%^:;\\=+-_()￥。“、\u4E00-\u9FA5\\d\\n]*$";
        NSPredicate *pred = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", pattern];
        BOOL isMatch = [pred evaluateWithObject:str];
        return isMatch;
    }
    
    // 字母、数字、中文正则判断（包括空格）（在系统输入法中文输入时会出现拼音之间有空格，需要忽略，当按return键时会自动用字母替换，按空格输入响应汉字）
    + (BOOL)isInputRuleAndBlank:(NSString *)str {
        NSString *pattern = @"^[a-zA-Z\u4E00-\u9FA5\\d\\s]*$";
        NSPredicate *pred = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", pattern];
        BOOL isMatch = [pred evaluateWithObject:str];
        return isMatch;
    }
    
    // 获得 kIntroTextViewMaxLength长度的字符
    + (NSString *)getSubString:(NSString*)string textMaxLength:(int)textMaxLength {
        NSStringEncoding encoding   = CFStringConvertEncodingToNSStringEncoding(kCFStringEncodingGB_18030_2000);
        NSData           *data      = [string dataUsingEncoding:encoding];
        NSInteger        length     = [data length];
        if (length > textMaxLength) {
            NSData *data1 = [data subdataWithRange:NSMakeRange(0, textMaxLength)];
            NSString *content = [[NSString alloc] initWithData:data1 encoding:encoding];//注意：当截取kIntroTextViewMaxLength长度字符时把中文字符截断返回的content会是nil
            if (!content || content.length == 0) {
                data1 = [data subdataWithRange:NSMakeRange(0, textMaxLength - 1)];
                content =  [[NSString alloc] initWithData:data1 encoding:encoding];
            }
            return content;
        }
        return nil;
    }
    
    + (NSString *)disable_emoji:(NSString *)text {
        NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"[^\\u0020-\\u007E\\u00A0-\\u00BE\\u2E80-\\uA4CF\\uF900-\\uFAFF\\uFE30-\\uFE4F\\uFF00-\\uFFEF\\u0080-\\u009F\\u2000-\\u201f\r\n]" options:NSRegularExpressionCaseInsensitive error:nil];
        NSString *modifiedString = [regex stringByReplacingMatchesInString:text
                                                                   options:0
                                                                     range:NSMakeRange(0, [text length])
                                                              withTemplate:@""];
        return modifiedString;
    }
    
    /**
     *  判断字符串中是否存在emoji
     * @param string 字符串
     * @return YES(含有表情)
     */
    - (BOOL)stringContainsEmoji:(NSString *)string {
        __block BOOL returnValue = NO;
        [string enumerateSubstringsInRange:NSMakeRange(0, [string length]) options:NSStringEnumerationByComposedCharacterSequences usingBlock:
         ^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop) {
             
             const unichar hs = [substring characterAtIndex:0];
             // surrogate pair
             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) {
                         returnValue = YES;
                     }
                 }
             } else if (substring.length > 1) {
                 const unichar ls = [substring characterAtIndex:1];
                 if (ls == 0x20e3) {
                     returnValue = YES;
                 }
                 
             } else {
                 // non surrogate
                 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;
                 }
             }
         }];
        
        return returnValue;
    }
    
    /**
     判断是不是九宫格
     @param string  输入的字符
     @return YES(是九宫格拼音键盘)
     */
    -(BOOL)isNineKeyBoard:(NSString *)string {
        NSString *other = @"➋➌➍➎➏➐➑➒";
        int len = (int)string.length;
        for(int i=0;i<len;i++)
        {
            if(!([other rangeOfString:string].location != NSNotFound))
                return NO;
        }
        return YES;
    }
    
    /**
     *  判断字符串中是否存在emoji
     * @param string 字符串
     * @return YES(含有表情)
     */
    - (BOOL)hasEmoji:(NSString*)string {
        NSString *pattern = @"[^\\u0020-\\u007E\\u00A0-\\u00BE\\u2E80-\\uA4CF\\uF900-\\uFAFF\\uFE30-\\uFE4F\\uFF00-\\uFFEF\\u0080-\\u009F\\u2000-\\u201f\r\n]";
        NSPredicate *pred = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", pattern];
        BOOL isMatch = [pred evaluateWithObject:string];
        return isMatch;
    }
    
    /**
     判断是不是九宫格
     @param string  输入的字符
     @return YES(是九宫格拼音键盘)
     */
    + (BOOL)isNineKeyBoard:(NSString *)string {
        NSString *other = @"➋➌➍➎➏➐➑➒";
        int len = (int)string.length;
        for(int i=0;i<len;i++)
        {
            if(!([other rangeOfString:string].location != NSNotFound))
                return NO;
        }
        return YES;
    }
    
    /**
     *  判断字符串中是否存在emoji
     * @param string 字符串
     * @return YES(含有表情)
     */
    + (BOOL)hasEmoji:(NSString*)string {
        NSString *pattern = @"[^\\u0020-\\u007E\\u00A0-\\u00BE\\u2E80-\\uA4CF\\uF900-\\uFAFF\\uFE30-\\uFE4F\\uFF00-\\uFFEF\\u0080-\\u009F\\u2000-\\u201f\r\n]";
        NSPredicate *pred = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", pattern];
        BOOL isMatch = [pred evaluateWithObject:string];
        return isMatch;
    }
    
    /**
     *  判断字符串中是否存在emoji
     * @param string 字符串
     * @return YES(含有表情)
     */
    + (BOOL)stringContainsEmoji:(NSString *)string {
        __block BOOL returnValue = NO;
        [string enumerateSubstringsInRange:NSMakeRange(0, [string length]) options:NSStringEnumerationByComposedCharacterSequences usingBlock:
         ^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop) {
             
             const unichar hs = [substring characterAtIndex:0];
             // surrogate pair
             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) {
                         returnValue = YES;
                     }
                 }
             } else if (substring.length > 1) {
                 const unichar ls = [substring characterAtIndex:1];
                 if (ls == 0x20e3) {
                     returnValue = YES;
                 }
                 
             } else {
                 // non surrogate
                 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;
                 }
             }
         }];
        
        return returnValue;
    }
    
    + (void)showAlertVCWithTitle:(NSString *)title message:(NSString *)message {
        UIAlertController *alertVC = [UIAlertController alertControllerWithTitle:title message:message preferredStyle:UIAlertControllerStyleAlert];
        UIAlertAction *OKAction = [UIAlertAction actionWithTitle:NSLocalizedString(@"OK", nil) style:UIAlertActionStyleDefault handler:nil];
        [alertVC addAction:OKAction];
        UIViewController *rootVC = [UIApplication sharedApplication].keyWindow.rootViewController;
        [rootVC presentViewController:alertVC animated:YES completion:nil];
    }
    
    @end
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转载于:https://juejin.im/post/5c9382f7f265da60df41074e

[Link 1]: https://link.juejin.im?target=https%3A%2F%2Fgithub.com%2FXiaoDongXie1024%2FXDXTextContentHandler
[iOS TextFiled_TextView]: https://link.juejin.im?target=https%3A%2F%2Fwww.jianshu.com%2Fp%2F888161c3b52d
[iOS TextFiled_TextView 1]: https://link.juejin.im?target=https%3A%2F%2Fxiaodongxie1024.github.io%2F2019%2F03%2F21%2F20190321_iOS_textContentFilter%2F
[iOS TextFiled_TextView 2]: https://juejin.im/post/5c9382f7f265da60df41074e