尝试使用 composer update.这就是它在错误中所说的内容.

Try using composer update. That is what it says in the error.

...You may be getting outdated dependencies. Run update to update them...

更新:

Composer 正在尝试查找文件夹 app/controllers/admin，它在 laravel 中不是标准文件夹.你确定这个文件夹存在吗?如果没有，您可以尝试从 composer.json 中删除这些和其他自定义文件夹，然后手动添加它们.您还可以创建目录并保持 composer.json 不变.

Composer is trying to find the folder app/controllers/admin which is no standard folder in laravel. Are you sure this folder exists? If not, you could try removing these, and other custom folders, from the composer.json, and add them manually. You could also create the directories and leave the composer.json untouched.