Ajax voting by pHP novice entry
AJAX Voting
#In the following example, we will demonstrate a voting program through which the voting results are displayed on the web page without refreshing The situation is displayed
First we write a php file, the code is as follows:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>php中文網(php.cn)</title>
<script>
function getVote(int) {
if (window.XMLHttpRequest) {
// IE7+, Firefox, Chrome, Opera, Safari 執(zhí)行代碼
xmlhttp=new XMLHttpRequest();
} else {
// IE6, IE5 執(zhí)行代碼
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange=function() {
if (xmlhttp.readyState==4 && xmlhttp.status==200)
{
document.getElementById("poll").innerHTML=xmlhttp.responseText;
}
}
xmlhttp.open("GET","demo.php?vote="+int,true);
xmlhttp.send();
}
</script>
</head>
<body>
<div id="poll">
<h3>你喜歡 PHP 和 AJAX 嗎?</h3>
<form>
是:
<input type="radio" name="vote" value="0" onclick="getVote(this.value)">
<br>否:
<input type="radio" name="vote" value="1" onclick="getVote(this.value)">
</form>
</div>
</body>
</html>Code explanation:
getVote() function will perform the following steps:
Create an XMLHttpRequest object
Create a function that is executed when the server response is ready
Send a request to a file on the server
Please note the parameters added to the end of the URL (q) (Contains the contents of the drop-down list)
Then create a demo.php file. The code is as follows:
<?php
$vote = htmlspecialchars($_REQUEST['vote']);
// 獲取文件中存儲的數據
$filename = "poll_result.txt";
$content = file($filename);
// 將數據分割到數組中
$array = explode("||", $content[0]);
$yes = $array[0];
$no = $array[1];
if ($vote == 0){
$yes = $yes + 1;
}
if ($vote == 1){
$no = $no + 1;
}
// 插入投票數據
$insertvote = $yes."||".$no;
$fp = fopen($filename,"w");
fputs($fp,$insertvote);
fclose($fp);
?>
<h2>結果:</h2>
<table>
<tr>
<td>是:</td>
<td>
<span style="display: inline-block; background-color:green;
width:<?php echo(100*round($yes/($no+$yes),2)); ?>px;
height:20px;" ></span>
<?php echo(100*round($yes/($no+$yes),2)); ?>%
</td>
</tr>
<tr>
<td>否:</td>
<td>
<span style="display: inline-block; background-color:red;
width:<?php echo(100*round($no/($no+$yes),2)); ?>px;
height:20px;"></span>
<?php echo(100*round($no/($no+$yes),2)); ?>%
</td>
</tr>
</table>Code explanation:
When the selected value is retrieved from JavaScript When sending to a PHP file, what will happen:
1. Get the contents of the "poll_result.txt" file
2. Put the file contents into a variable and add 1## to the selected variable
#3. Write the results to the "poll_result.txt" file4. Output the graphical voting results
