创建一个emoji.js工具类

    //把utf16的emoji表情字符进行转码成八进制的字符
export function utf16toEntities(str) {
  var patt = /[\ud800-\udbff][\udc00-\udfff]/g; // 检测utf16字符正则  
  return str.replace(patt, function (char) {
      var H, L, code;
      if (char.length === 2) {
          H = char.charCodeAt(0); // 取出高位  
          L = char.charCodeAt(1); // 取出低位  
          code = (H - 0xD800) * 0x400 + 0x10000 + L - 0xDC00; // 转换算法  
          return "&#" + code + ";";
      } else {
          return char;
      }
  });
}

//将编码后的八进制的emoji表情重新解码成十六进制的表情字符
export function entitiesToUtf16(str) {
  return str.replace(/&#(\d+);/g, function (match, dec) {
      let H = Math.floor((dec - 0x10000) / 0x400) + 0xD800;
      let L = Math.floor(dec - 0x10000) % 0x400 + 0xDC00;
      return String.fromCharCode(H, L);
  });
}

在需要编解码的地方进行调用

    import {utf16toEntities,entitiesToUtf16} from '@/utils/emoji'
    var a = utf16toEntities("表情包")
    var b = entitiesToUtf16(a)