- GET
- HEAD
- POST
:仅POST方法的Content-Type值等于下列之一才算作简单请求:
- Content-Type
- text/plain
- multipart/form-data
- application/x-www-form-urlencoded
- Accept
- Accept-Language
- Content-Language
- Content-Type
- DPR
- Downlink
- Save-Data
- Viewport-Width
- Width
方法发起一个预检请求到服务器,以获知服务器是否允许该实际请求,如果服务端同意,再发送实际请求,这样可以避免跨域请求对服务器的用户数据产生未预期的影响。预检请求须满足所有下述条件:
- OPTIONS
- PUT
- DELETE
- CONNECT
- OPTIONS
- TRACE
- PATCH
- Accept
- Accept-Language
- Content-Language
(but note the additional requirements below)
- Content-Type
- DPR
- Downlink
- Save-Data
- Viewport-Width
- Width
的值不属于下列之一:
- Content-Type
- application/x-www-form-urlencoded
- multipart/form-data
- text/plain
来源: http://www.cnblogs.com/XiongMaoMengNan/p/7533203.html