UITextField限制表情输入，限制输入长度

一、需求是输入框输入限制表情的输入，限制输入长度

1、判断是否是九宫格输入

+ (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;
}

2、判断是否是emoji表情输入

+ (BOOL)stringContainsEmoji:(NSString *)string {
    
    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:string
                                                               options:0
                                                                 range:NSMakeRange(0, [string length])
                                                          withTemplate:@""];
    
    return modifiedString.length == 0? YES : NO;
}

3、在textField代理方法里判断

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
    
    if ([FSLMethod isNineKeyBoard:string]) {
        return YES;
    }
    if ([FSLMethod stringContainsEmoji:string]) {
        
        return NO;
    }else
        
        return YES;
}

二、输入长度限制
1、给要判断的textField添加监听方法

[nameTextField addTarget:self action:@selector(textFieldEditChanged:) forControlEvents:UIControlEventEditingChanged];

2、在监听方法里做判断限制

- (void)textFieldEditChanged:(UITextField *)textField
{
    [self changeSubBtnBackgroudImage];
    if (textField == self.enterpriseTextField) {  // 企业全称

        [self textFieldEditChanged:textField withMaxLength:30];
    }else if (textField == self.nameTextField) { // 名字

        [self textFieldEditChanged:textField withMaxLength:10];
    }else if (textField == self.positionTextField) { // 职位

        [self textFieldEditChanged:textField withMaxLength:10];
    }else if (textField == self.addrTextField) {             // 详细地址

        [self textFieldEditChanged:textField withMaxLength:50];
    }
}

- (void)textFieldEditChanged:(UITextField *)textField withMaxLength:(NSInteger)maxlength
{
     NSString *toBeString = textField.text;
    NSString *lang = [[UITextInputMode currentInputMode] primaryLanguage]; // 键盘输入模式
    if ([lang isEqualToString:@"zh-Hans"]) { // 简体中文输入，包括简体拼音，健体五笔，简体手写
        UITextRange *selectedRange = [textField markedTextRange];
        //获取高亮部分
        UITextPosition *position = [textField 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) {
            if (toBeString.length > maxlength) {
                textField.text = [toBeString substringToIndex:maxlength];
//                [self alertInfo:@"商讯标签超出字数限制"];
//                self.titleRightLabel.text = @"30/30";
                textField.text = [textField.text substringToIndex:maxlength];
                
            }
        }
        // 有高亮选择的字符串，则暂不对文字进行统计和限制
        else{
            
        }
    }
    // 中文输入法以外的直接对其统计限制即可，不考虑其他语种情况
    else{
        if (toBeString.length > maxlength) {
            textField.text = [toBeString substringToIndex:maxlength];
//            [self alertInfo:@"商讯标签超出字数限制"];
//            self.titleRightLabel.text = @"30/30";
            textField.text = [textField.text substringToIndex:maxlength];
        }
    }
}