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characters

HTTP 304 Not Modified客户端重定向响应代码指示不需要重新传输请求的资源。这是对缓存资源的隐式重定向。这发生在请求方法是安全的时候,比如一个 GET或者一个HEAD请求,或者当请求是有条件的并且使用一个 If-None-Match或者一个If-Modified-Since标头时。

等效200 OK响应会包括头Cache-ControlContent-LocationDateETagExpires,和Vary

许多开发人员工具的浏览器网络面板会产生无关的请求,导致304响应,因此开发人员可以看到对本地缓存的访问。

状态

304 Not Modified

规范

规范

标题

RFC 7232,第4.1节:304未修改

超文本传输协议(HTTP / 1.1):条件请求

浏览器兼容性

Feature

Chrome

Edge

Firefox

Internet Explorer

Opera

Safari

Basic Support

(Yes)

(Yes)

(Yes)

(Yes)

(Yes)

(Yes)

Feature

Android

Chrome for Android

Edge mobile

Firefox for Android

IE mobile

Opera Android

iOS Safari

Basic Support

(Yes)

(Yes)

(Yes)

(Yes)

(Yes)

(Yes)

(Yes)

兼容性说明

  • 如果此响应错误地包含持久连接上的主体,则浏览器行为会有所不同。有关更多详细信息,请参阅204无内容

  • If-Modified-Since

  • If-None-Match

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