Question

我有一个投票系统，允许用户对项目进行upvote和downvote。我希望改进系统，因为用户可以多次投票。下面你可以看到我的代码。

<h4> Votes </h4>

<table>
<tr>
<th>Up-Votes</th>
<th>Down-Votes</th>
<tr/>
<tr>
<?php 
 mysql_connect("localhost", "root", "PASS") or die(mysql_error()); 
 mysql_select_db("DBNAME") or die(mysql_error()); 

 if ( isset( $_POST['Upvote'] ) )
 {

 mysql_query ("UPDATE reports SET up = up + 1 WHERE reportID = $id"); 

 } else if (isset( $_POST['Downvote'] ))
{
 mysql_query ("UPDATE reports SET down = down + 1 WHERE reportID = $id"); 
}

$data = mysql_query("SELECT * FROM reports WHERE reportID = $id") or die(mysql_error()); 

while($ratings = mysql_fetch_array( $data )) 
{ 

Echo "<td>" .$ratings['up']."</td>"; 
Echo "<td>" .$ratings['down']."</td>"; 

} 

?>
</tr>
</table>
<br/>
<form method='POST'>
<input type='submit' value='up' name='Upvote' class="myButton">
<input type='submit' value='down' name='Downvote' class="myButton">
</form>

是否有人有任何可以防止重复投票的建议？

我的系统上可能存在数千个项目，我不确定如何让用户免于对特定报告进行投票

干杯

Answer 1

建立投票数据库：

CREATE TABLE Votes (
    Value int,
    User int
);

Value对于upvotes为1，对于downvotes为-1，User为用户ID。只需在投票时覆盖现有列：

if (mysqli_fetch_array(mysqli_query($con, "SELECT FROM `Votes` WHERE `User` = ".$theuserid)) {
    mysqli_query("UPDATE `Votes` SET `Value` = ".$mynewvalue." WHERE `User` = ".$theuserid);
} else {
    mysqli_query("INSERT INTO `Votes`(`User`,`Value`) VALUES (".$theuserid.",".$mynewvalue.")");
}

要获得投票总数，请使用：

SELECT sum(Value) FROM Votes

Answer 2

然后在你的php

中

$voted = $this->getUserVoted(escape($_POST['user']));
    if($voted) { $this->addError($language_votes['you_already_rated']); return; }

停止多次投票

2 个答案: