Three methods for PHP to obtain form data

The following are three methods for obtaining form data in PHP:

Form partCode:

<Form name = "form1" method = "Post" Action = "">

<Input type = "text" name = "username">

<Input type = "Submit" name = "Submit" value = "Submit">

</Form>

Get form:

<? PHP

Echo ($ http_post_vars ["username"]);

Echo ($ _ request ["username"]);

Echo ($ username );

?>

Method 1 is a common method in versions earlier than 4.0, regardless of how register_globals is set;

Method 2 is a common method in version 4.2 and later, regardless of how register_globals is set;

Method 3 is applicable when register_globals = on is set in PHP. ini.

Supplement:

The content in the $ _ request is actually from $ _ get $ _ post $ _ cookie. The disadvantage is that the variable cannot be determined whether it comes from get post or cookie. It is not applicable to scenarios with strict requirements.