您尝试调用 split 的类型是 string|string[]，这意味着value 可以是 string 或 string[]，为了让 TypeScript 满意，两种类型都必须有 split 方法.如果您确信它始终是一个字符串，请在调用 split 之前更新定义(如果可能)或强制转换为 string:

The type you are trying to invoke split on is string|string[], which means that value may be either a string or a string[], in order for TypeScript to be happy, BOTH types must have a split method. If you are confident that it will always be a string, either update the definition (if possible) or cast to a string before calling split:

(<string>req.headers.authorization).split

或

(req.headers.authorization as string).split