412 Precondition Failed - [ HTTP 中文开发手册 ] - 在线原生手册

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文字

HTTP 412 Precondition Failed客户端错误响应代码指示对目标资源的访问已被拒绝。这种情况与上比其他方法条件请求GET或者HEAD当被定义的条件If-Unmodified-Since或If-None-Match头部不被满足。在这种情况下，无法进行请求（通常是上载或修改资源），并且发送此错误响应。

状态

412 Precondition Failed

规范

规范	标题
RFC 7232，第4.2节：412先决条件失败	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)

也可以看看

304

If-Unmodified-Since

If-None-Match

428