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-- Learning not just technology, but dreams too! Home HTML JAVASCRIPT CSS VUE REACT PYTHON3 JAVA C C++ C# AI GO SQL LINUX VS CODE BOOTSTRAP GIT Local Bookmarks PHP Tutorial PHP Tutorial PHP Introduction PHP Installation PHP Syntax PHP Variables PHP echo/print PHP EOF (heredoc) PHP Data Types PHP Type Comparison PHP Constants PHP Strings PHP Operators PHP If...Else PHP Switch PHP Arrays PHP Array Sorting PHP Superglobals PHP While Loop PHP For Loop PHP Functions PHP Magic Constants PHP Namespaces PHP Object-Oriented Programming PHP Quiz PHP Forms PHP Forms PHP Form Validation PHP Forms - Required Fields PHP Forms - Email and URL Validation Complete PHP Form Example PHP $_GET Variable PHP $_POST Variable Advanced PHP Tutorials PHP Multidimensional Arrays PHP Dates PHP Includes PHP Files PHP File Uploads PHP Cookies PHP Sessions PHP E-mail PHP Secure E-mail PHP Errors PHP Exceptions PHP Filters Advanced PHP Filters PHP JSON New Features in PHP 7 New Features in PHP 7 PHP Databases Introduction to PHP MySQL Connecting to PHP MySQL Creating a Database with PHP MySQL Creating Tables with PHP MySQL Inserting Data with PHP MySQL Inserting Multiple Records with PHP MySQL PHP Prepared Statements Reading Data with PHP MySQL PHP MySQL WHERE Clause PHP MySQL ORDER BY PHP MySQL UPDATE PHP MySQL DELETE PHP ODBC PHP XML XML Expat Parser XML DOM XML SimpleXML PHP and AJAX Introduction to AJAX AJAX in PHP AJAX Databases AJAX XML AJAX Real-Time Search AJAX RSS Reader AJAX Voting PHP Reference Manual PHP Array PHP Calendar PHP cURL PHP Date PHP Directory PHP Error PHP Filesystem PHP Filter PHP FTP PHP HTTP PHP Libxml PHP Mail PHP Math PHP Misc PHP MySQLi PHP PDO PHP SimpleXML PHP String PHP XML PHP Zip PHP Time Zones PHP Image Processing PHP RESTful PHP PCRE Available PHP Functions PHP Composer PHP Example - AJAX RSS Reader PHP 5 Array Functions In-Depth Exploration Data Management Scripting Languages script Programming Languages Development Tools Web Services Computer Hardware Computers Web Design and Development PHP Example - AJAX Voting AJAX Voting In the following example, we will demonstrate a voting program where the voting results are displayed without refreshing the webpage. Do you like PHP and AJAX? Yes: No: Example Explanation - HTML Page When the user selects one of the options above, the function named "getVote()" is executed. This function is triggered by the "onclick" event. The code for the poll.html file is as follows: function getVote(int) { if (window.XMLHttpRequest) { // IE7+, Firefox, Chrome, Opera, Safari execute this code xmlhttp = new XMLHttpRequest(); } else { // IE6, IE5 execute this code xmlhttp = new ActiveXObject("Microsoft.XMLHTTP"); } xmlhttp.onreadystatechange = function() { if (xmlhttp.readyState == 4 && xmlhttp.status == 200) { document.getElementById("poll").innerHTML = xmlhttp.responseText; } }; xmlhttp.open("GET", "poll_vote.php?vote=" + int, true); xmlhttp.send(); } The getVote() function performs the following steps: Create an XMLHttpRequest object Create a function that runs when the server response is ready Send a request to a file on the server Note the parameter added to the end of the URL (q), which contains the content of the dropdown list PHP File The server page called by JavaScript above is a PHP file named "poll_vote.php":

Results:

Yes:	<span style="display: inline-block; background-color: green; width: px; height: 20px;"> %
No:	<span style="display: inline-block; background-color: red; width: px; height: 20px;"> %

When the selected value is sent from JavaScript to the PHP file, the following happens: Retrieve the contents of the "poll_result.txt" file Store the file contents in a variable and increment the selected option by 1 Write the result back to the "poll_result.txt" file Output the graphical voting results Text File The text file ("poll_result.txt") stores data from the voting program. It stores data like this: 3||4 The first number represents the number of "Yes" votes, and the second number represents the number of "No" votes. Note: Remember to allow only your web server to edit this text file. Do not grant access to anyone else except the web server (PHP). PHP Example - AJAX RSS Reader PHP 5 Array Functions Byte Ark Coding Plan Supports mainstream large models such as Doubao, GLM, DeepSeek, Kimi, MiniMax, etc., directly provided by official sources—stable and reliable. ¥9.9 / month Activate Now iFLYTEK Starry Sky Coding Plan Includes free model call credits for DeepSeek, GLM, Kimi, MiniMax—a one-stop platform for experience and deployment. ¥3.9 / month Activate Now 2 Notes Write Note    Daughter of the Study God   dff***j@qq.com 128 This is very insecure! Attackers can break it with a short piece of code! // Infinite loop script var Vote = 0; // Your vote. setInterval(function(){ getVote(Vote); }, 2000); How can it be made more secure? You can use cookies to record votes, so attackers would also have to clear the cookies. if(empty($_COOKIE)) { setcookie("voted","yes!",ime()+60*60*24*365); } else { die("You've already voted!"); } Daughter of the Study God    Daughter of the Study God   dff***j@qq.com 8 years ago (2018-05-08)    Now Internet   che***nzho@aliyun.com 149 I strongly disagree with @Daughter of the Study God: “How can it be made more secure? Use cookies to record votes, so attackers would have to clear the cookies.” That’s actually not ideal either. As long as I never carry cookies, I can keep submitting votes to cheat, like this: <?php // Based on browser packet capture, the voting URL is as follows: $api_url = " for($i=0; $i<1000; $i++){ // Loop 1000 times using file_get_contents to access the voting URL and cheat file_get_contents($api_url); } To prevent cheating, you still need to limit IP addresses and require cookies. Alternatively, you could require users to log in before voting, perhaps by integrating WeChat login so users must log in via WeChat to cast their votes. Now Internet    Now Internet   che***nzho@aliyun.com 6 years ago (2020-02-05) Category Navigation Python / Data Science AI / Intelligent Development Frontend Development Backend Development Databases Mobile Development DevOps / Engineering Programming Languages Computer Fundamentals XML / Web Services .NET Website Building Advertisement PHP Tutorial PHP Tutorial PHP Introduction PHP Installation PHP Syntax PHP Variables PHP echo/print PHP EOF (heredoc) PHP Data Types PHP Type Comparison PHP Constants PHP Strings PHP Operators PHP If...Else PHP Switch PHP Arrays PHP Array Sorting PHP Superglobals PHP While Loops PHP For Loops PHP Functions PHP Magic Constants PHP Namespaces PHP Object-Oriented Programming PHP Quiz PHP Forms PHP Forms PHP Form Validation PHP Forms - Required Fields PHP Forms - Email and URL Validation Complete PHP Form Example PHP $_GET Variable PHP $_POST Variable Advanced PHP Tutorials PHP Multidimensional Arrays PHP Dates PHP Includes PHP Files PHP File Uploads PHP Cookies PHP Sessions PHP E-mail PHP Secure E-mail PHP Errors PHP Exceptions PHP Filters Advanced PHP Filters PHP JSON New Features in PHP 7 New Features in PHP 7 PHP Databases Introduction to PHP MySQL Connecting to PHP MySQL Creating Databases with PHP MySQL Creating Tables with PHP MySQL Inserting Data with PHP MySQL Inserting Multiple Records with PHP MySQL PHP Prepared Statements Reading Data with PHP MySQL PHP MySQL WHERE Clause PHP MySQL ORDER BY PHP MySQL UPDATE PHP MySQL DELETE PHP ODBC PHP XML XML Expat Parser XML DOM XML SimpleXML PHP and AJAX Introduction to AJAX AJAX in PHP AJAX Databases AJAX XML AJAX Real-Time Search AJAX RSS Reader AJAX Voting PHP Reference Manual PHP Array PHP Calendar PHP cURL PHP Date PHP Directory PHP Errors PHP Filesystem PHP Filters PHP FTP PHP HTTP PHP Libxml PHP Mail PHP Math PHP Misc PHP MySQLi PHP PDO PHP SimpleXML PHP String PHP XML