我需要将thumb_添加到url的文件名中leturl="https://firebasestorage.googleapis.com/v0/b/xxx-xx.xxxx.com/o/images%2Fjondoe%2F-ASDFASDFSDFAS.png?alt=media&token=xxxxx"将其转换为leturl="https://firebasestorage.googleapis.com/v0/b/xxx-xx.xxxx.com/o/images%2Fjondoe%2Fthumb_-ASDFASDFSDFAS.png?alt=media&token=xxxxx"我使用了这个