Data Transport Methods Across Webpages (Part 2/2)

It's time to look at the other method of sending data.

The POST method

The POST method is a more effective way of sending data. The data is embedded in the headers and sent to the next page.

<form method="POST">
    <input name="x" value="test">
    <input name="y" value="12345">
    <input type="submit" name="btSubmit" value="submit">
</form>

Pros

Way more secure than GET - All data is hidden. Note that I said more, not totally secure. POST has its vulnerabilities which we'll explore at a later date.

Versatility in data formats and lengths - You can send long paragraphs of text, in addition to everything you can already send via GET. Also, and this is no trivial matter, you can send binary files.

Cons

Breaks page flow - clicking on the Back button or reloading the page will cause a popup to appear, asking if you wish to re-send your data. Depending on the nature of your data, re-sending the data may cause something to break. Below is a sample of this popup. The message varies from browser to browser.

Use POST for...

... almost everything. Long and complex data, especially files.

... data that needs to be kept private, e.g. transactions or passwords.

Do not use POST for...

... pages you may want to be cached.

... pages where backwards-forwards navigation is an issue.

The methods in a nutshell

The GET method has a well-deserved reputation for being widely used - sometimes overused. I once spoke to a software developer who looked upon GET with disdain and was of the opinion that GET is an unsafe and "cheap" way of sending data. She was only half right. GET is all that, and so much more. There is a place for everything, and GET is no exception. GET has its uses - some of which are not immediately apparent to people who aren't web developers.

On the other hand, I've been guilty of using POST when it would have been more beneficial to use a GET instead. Oh, well. Live and learn.

The lesson for the day is - the correct tool for the correct job. Whatever you end up choosing, exercise appropriate caution.

That's all for the time being. I'll POST again soon. (snicker)
T___T