vue3 + ts 从数据中拿到单个属性，并存为字符串和数组

let cart_idsAll = "";
      //从对象中遍历拿到指定属性
      selectArrey.value.forEach(function (item) {
        //存为字符串
        (cart_idsAll as any) += (item as any).goods_id + ","; 
      });
      //将字符串的最后一","删除，并根据","转为数组
      (cart_idsAll as any) = cart_idsAll.substring(0,cart_idsAll.length-1).split(","); 
      if (cart_idsAll != "") {
        console.log("cart_idsAll", cart_idsAll);
      } else {
        ElMessage({
          message: "没有选中任何订单！",
          type: "warning",
        });