How to set form submission method in PHP

When developing a Web website or application, we often need to add forms to the web page for users to fill out. This form data usually needs to be submitted to the server in a processable format for further processing. In PHP, we can use different ways to handle form submission. This article will introduce how to set the form submission method.

GET method to submit the form

The GET method is a request method in the HTTP protocol, which appends the form data to the end of the URL in order to send the data to the server. When submitting a form using GET, the form data will appear in the URL, so it is not suitable for submitting sensitive data such as passwords. Compared with the POST method, the amount of data submitted by the GET method is also more limited.

To set the form submission method to GET, we need to add a method="get" attribute to the form tag, as shown below:

<form action="process.php" method="get">
  <!-- 表单元素 -->
  <input type="text" name="username">
  <input type="password" name="password">
  <input type="submit" value="提交">
</form>

In In the above code, the action attribute specifies the target URL for form submission, and the method attribute specifies the form submission method. When the user clicks the "Submit" button, the form data will be converted into URL parameters and appended to the URL specified by the action attribute, for example:

http://example.com/process.php?username=bob&password=123456

In PHP, we can Use the $_GET super global array to access the form data submitted in the GET method, as follows:

$username = $_GET['username'];
$password = $_GET['password'];

If the form data contains Chinese or other non-ASCII characters, we need to use The urlencode() function URL-encodes it so that these characters can be processed correctly.

POST method to submit the form

The POST method is another request method in the HTTP protocol. Compared with the GET method, the POST method has no data size limit and can submit more data. When you submit a form using POST, the form data is sent to the server as the HTTP message body, not as URL parameters. Therefore, the POST method is more suitable for submitting sensitive data, such as passwords, credit card numbers, etc.

To set the form submission method to POST, we need to add a method="post" attribute to the form tag, as shown below:

<form action="process.php" method="post">
  <!-- 表单元素 -->
  <input type="text" name="username">
  <input type="password" name="password">
  <input type="submit" value="提交">
</form>

In In the above code, the action attribute specifies the target URL for form submission, and the method attribute specifies the form submission method. When the user clicks the Submit button, the form data is encapsulated in the HTTP message body and sent to the URL specified by the action attribute. In PHP, we can use the $_POST super global array to access the form data submitted in POST mode, as shown below:

$username = $_POST['username'];
$password = $_POST['password'];

If the form data contains Chinese or other non-ASCII characters, We can set the character set using the following code at the top of the PHP script:

header('Content-Type: text/html; charset=utf-8');

Use the $_REQUEST array

In addition to using $_GET or $_POST In addition to the super global array, PHP also provides a super global array named $_REQUEST to access form data. $_REQUESTThe array contains a collection of GET, POST and COOKIE data. It is not an array of a specific submission method, but a form data that can access multiple submission methods at the same time.

The usage of this array is similar to $_GET and $_POST, as shown below:

$username = $_REQUEST['username'];
$password = $_REQUEST['password'];

It should be noted that using $_REQUESTYou need to be very careful when using arrays as it may cause security issues.

Summary

In PHP, we use different ways to handle form submission, including GET method, POST method and $_REQUEST array. The GET method is suitable for submitting less data, while the POST method is more suitable for submitting large amounts of data and sensitive data. Use the $_REQUEST array to access form data from multiple submission methods at the same time. Developers need to choose the appropriate form submission method based on specific application scenarios and data requirements to ensure the normal operation of the application and data security.

The above is the detailed content of How to set form submission method in PHP. For more information, please follow other related articles on the PHP Chinese website!