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Introduction to how to solve the problem of repeated form submission in PHP_PHP Tutorial
- WBOYOriginal
- 2016-07-13 10:27:07916browse
Introduction to how to solve the problem of repeated form submission in PHP
Repeated submission is a problem we often encounter in development. In addition to using js to prevent repeated submission of forms, we can also use php to prevent repeated submission.
Example 1
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/*
* How to prevent repeated submission of forms in php
*/
session_start();
if (empty($_SESSION['ip'])) {//The first write operation, determine whether the IP address is recorded, so as to know whether to write to the database
$_SESSION['ip'] = $_SERVER['REMOTE_ADDR']; //First write, paving the way for subsequent refresh or retreat decisions
//..........//Write to database operation
} else {//There has been an operation after the first write, so it will no longer be written to the database
echo 'Please do not refresh and go back again'; //Write some already written prompts or other things
}
?>
Specific principles
Session scope variable token to prevent.
1. Open session:
session_start();
2. If there is a form submission
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if (isset($token))
The token is included in the form in hidden form.
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3. If the form is submitted repeatedly
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1.if ($_SESSION["token"] != $token) {
2. // Do not allow repeated submissions, handle them here
3. // header("location:".$_SERVER['PHP_SELF']);
4.} else {
5. // Normal form submission, processed here
6. // echo "Submitted";
7.}
4. Set token value
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1.$token = mt_rand(0,1000000);
2.$_SESSION['token'] = $token;
Introduction to how to solve the problem of repeated form submission in PHP
------Solution--------------------
Should users be allowed to submit for the second time under normal circumstances?
------Solution--------------------
Actually I didn’t do that
Because mature projects generally separate views and forward them through routing! This will not happen!