为什么axios的配置里需要单独对不同类型的请求体进行转换？ Why does Axios require separate conversion of different types of request bodies in its configuration?

[singleeeee]

Why does Axios require separate conversion of different types of request bodies in its configuration? Axios had already handled them, we just need to declare the type of request header and it will make effect.

为什么Axios在其配置中要求对不同类型的请求体进行单独转换？Axios已经处理了它们，我们只需要声明请求头的类型，它就会生效。

是因为axios内部封装的转换方法有缺陷吗？
Is it because there is a defect in the conversion method encapsulated within Axios?