Javascript 遍历特定类下的 textarea 字段以从名称以 Gift Message 作为子字符串的 textarea 字段中删除表情符号

我只是想用下面的代码和逻辑来解决这个问题，寻找一个纯JavaScript的解决方案.我一直无法获取textarea字段的值，该字段的名称包含作为其名称子字符串的礼物消息.你能帮我修一下吗？

HTML格式如下:

<span class="bold_option_element">
    <textarea name="properties[Enter Gift Message Below. NO EMOJIS PLEASE. Remember to sign your name! ]" class="ta_570739_262324" maxlength="1000">
    </textarea>
  <textarea name="properties[Test Gift ]" class="ta_570739_262324" maxlength="1000">
    </textarea>
</span>

JavaScript:

<script>
    {%- comment -%}
        This block of code checks if emojis are present in gift message, on keyup event
        Logic:
        1. Get value of textarea field for gift message.
        2. Get the textarea "bold_option_element" fields whose name has "GiftMessage" after stripping all blanks.
        3. Return false if emojis are present.
        Refer: https://melvingeorge.me/blog/check-if-string-contain-emojis-javascript for emoji validation
    {%- endcomment -%}
    window.onkeyup = function(e) {
        // Get gift message string.
        giftMessage = "Hello ???? ????";
        let textAreaElements = document.getElementsByClassName('bold_option_element');
        console.log(textAreaElements);
        const regexExp = /(\u00a9|\u00ae|[\u2000-\u3300]|\ud83c[\ud000-\udfff]|\ud83d[\ud000-\udfff]|\ud83e[\ud000-\udfff])/gi;
        if (regexExp.test(giftMessage)) {
            alert("No EMOJIs are allowed in the Gift Message. EMOJIs have been deleted in the Gift Messsage. Edit your Gift Message and 'Add to Cart'");
            return false;
        }
        return true;    
    };
</script>

链接到jsfiddle:https://jsfiddle.net/pramodraam/vhqyj15m/6/