Posted By: Anonymous
I’ve only recently been getting involved with PHP/AJAX/jQuery and it seems to me that an important part of these technologies is that of
First, what is the difference between
GET? Through experimenting, I know that
GET appends the returning variables and their values to the URL string
So, is this the only difference or are there specific rules or conventions for using one or the other?
Second, I’ve also seen
GET outside of PHP: also in AJAX and jQuery. How do
GET differ between these 3? Are they the same idea, same functionality, just utilized differently?
POST are two different types of HTTP requests.
According to Wikipedia:
GET requests a representation of the specified resource. Note that GET should not be used for operations that cause side-effects, such as using it for taking actions in web applications. One reason for this is that GET may be used arbitrarily by robots or crawlers, which should not need to consider the side effects that a request should cause.
POST submits data to be processed (e.g., from an HTML form) to the identified resource. The data is included in the body of the request. This may result in the creation of a new resource or the updates of existing resources or both.
GET is used to retrieve remote data, and
POST is used to insert/update remote data.
HTTP/1.1 specification (RFC 2616) section 9 Method Definitions contains more information on
POST as well as the other HTTP methods, if you are interested.
In addition to explaining the intended uses of each method, the spec also provides at least one practical reason for why
GET should only be used to retrieve data:
Authors of services which use the HTTP protocol SHOULD NOT use GET based forms for the submission of sensitive data, because this will cause this data to be encoded in the Request-URI. Many existing servers, proxies, and user agents will log the request URI in some place where it might be visible to third parties. Servers can use POST-based form submission instead
Finally, an important consideration when using
GET for AJAX requests is that some browsers – IE in particular – will cache the results of a
GET request. So if you, for example, poll using the same
GET request you will always get back the same results, even if the data you are querying is being updated server-side. One way to alleviate this problem is to make the URL unique for each request by appending a timestamp.