vue添加过滤器，超出文字省略号显示

<el-table-column label="输入输出字段" width="200">      
   <template slot-scope="scope">            
       <span>{{scope.row.columnDatas | ellipsis}}</span>         
   </template> 
</el-table-column>

添加filters

export default {
  filters: {
      ellipsis(value) { 
        if (!value) return "";
        if (value.length > 22) {
          return value.slice(0, 22) + "...";
        }
        return value;
      }
   },
}