据我所知,有三种类型:

不要使用GET和POST 不要使用POST而使用GET 你用哪一个都不重要。

我对这三种情况的假设正确吗?如果有,每个案例都有哪些例子?


当前回答

Gorgapor, mod_rewrite仍然经常使用GET。它只是允许将一个更友好的URL转换为一个带有GET查询字符串的URL。

其他回答

短的版本

GET:通常用于已提交的搜索请求,或者任何您希望用户能够再次调出确切页面的请求。

GET的优点:

url可以安全地添加书签。 页面可以安全地重新加载。

GET的缺点:

变量作为名称-值对通过url传递。(安全风险) 可以传递的变量数量有限。(基于浏览器。例如,Internet Explorer被限制为2048个字符。)

POST:用于更高安全性的请求,其中数据可能用于更改数据库,或者您不希望别人添加书签的页面。

POST的优点:

url中不显示名称-值对。(安全+= 1) 可以通过POST传递无限数量的名称-值对。参考。

POST的缺点:

使用POST数据的页面不能被书签。(如果你愿意的话。)

完整版

直接来自超文本传输协议——HTTP/1.1:

9.3 GET The GET method means retrieve whatever information (in the form of an entity) is identified by the Request-URI. If the Request-URI refers to a data-producing process, it is the produced data which shall be returned as the entity in the response and not the source text of the process, unless that text happens to be the output of the process. The semantics of the GET method change to a "conditional GET" if the request message includes an If-Modified-Since, If-Unmodified-Since, If-Match, If-None-Match, or If-Range header field. A conditional GET method requests that the entity be transferred only under the circumstances described by the conditional header field(s). The conditional GET method is intended to reduce unnecessary network usage by allowing cached entities to be refreshed without requiring multiple requests or transferring data already held by the client. The semantics of the GET method change to a "partial GET" if the request message includes a Range header field. A partial GET requests that only part of the entity be transferred, as described in section 14.35. The partial GET method is intended to reduce unnecessary network usage by allowing partially-retrieved entities to be completed without transferring data already held by the client. The response to a GET request is cacheable if and only if it meets the requirements for HTTP caching described in section 13. See section 15.1.3 for security considerations when used for forms. 9.5 POST The POST method is used to request that the origin server accept the entity enclosed in the request as a new subordinate of the resource identified by the Request-URI in the Request-Line. POST is designed to allow a uniform method to cover the following functions: Annotation of existing resources; Posting a message to a bulletin board, newsgroup, mailing list, or similar group of articles; Providing a block of data, such as the result of submitting a form, to a data-handling process; Extending a database through an append operation. The actual function performed by the POST method is determined by the server and is usually dependent on the Request-URI. The posted entity is subordinate to that URI in the same way that a file is subordinate to a directory containing it, a news article is subordinate to a newsgroup to which it is posted, or a record is subordinate to a database. The action performed by the POST method might not result in a resource that can be identified by a URI. In this case, either 200 (OK) or 204 (No Content) is the appropriate response status, depending on whether or not the response includes an entity that describes the result.

我的一般经验法则是,当您向服务器发出不打算改变状态的请求时使用Get。post是为更改状态的服务器请求保留的。

另一个区别是POST通常需要两个HTTP操作,而GET只需要一个。

编辑:我应该澄清一下——对于常见的编程模式。一般来说,用一个直接的HTML网页来回复一个POST是一个有问题的设计,原因有很多,其中之一就是在按下后退按钮时出现烦人的“您必须重新提交这个表单,您希望这样做吗?”

HTTP Post数据对数据量没有指定的限制,因为不同的浏览器对GET有不同的限制。RFC 2068声明:

服务器应谨慎 取决于URI长度大于255 字节,因为一些旧的客户端或 代理实现可能不正确 支持这些长度

具体来说,您应该根据它们的用途选择正确的HTTP结构。HTTP GET不应该有副作用,可以被HTTP代理等安全地刷新和存储。

当您想要针对url资源提交数据时,使用HTTP POST。

使用HTTP GET的一个典型示例是在搜索中,即搜索?查询=我+查询 使用HTTP POST的一个典型示例是向在线表单提交反馈。

除了许多浏览器的长度限制不同之外,还有语义上的差异。get应该是“安全的”,因为它们是只读操作,不会改变服务器状态。post通常会改变状态,并在重新提交时给出警告。搜索引擎的网络爬虫可能会生成get,但不应该生成post。

如果希望读取数据而不改变状态,则使用GET;如果希望更新服务器上的状态,则使用POST。