建设一个简单交互的网站(五)
8. 投票系统
在许多时候，我们需要收集上网者和网友们的意见。例如：新版页面与旧版页面的比较；对某一事情的看法；对体育比赛结果的预测等等。这时候，你需要一个非常有效的网上调查系统。使用PHP就可以非常方便地实现你的这一构想。
8.1 投票系统（mypolls.php3）：
<?
＄status=0;
if(isset(＄polled)&&(＄polled=="c-e")){
＄status=1;
}
#echo "＄status";
if(isset(＄poll)&&(＄status==0)){
setcookie("polled","c-e",time()+86400,"/");#time=24h
}
?>
<html>
<head>
<title>新版页面调查</title>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<style type="text/css">
<!--
.tb { border="1" bordercolor="#009933" cellspacing="0" font-size: 9pt; color: #000000}
.head { font-family: "宋体"; font-size: 12pt; font-weight: bold; color: #009933; text-decoration: none}
.pt9 { font-size: 9pt}
a.p9:link { font-size: 9pt; color: #000000; text-decoration: none}
a.p9:visited { font-size: 9pt; color: #000000; text-decoration: none }
a.p9:hover { font-size: 9pt; color: #FF0000; text-decoration: underline}
a.p9:active { font-size: 9pt; color: #FF0000; text-decoration: underline }
-->
</style>
</head>
<body bgcolor="#FFFFFF">
<div class="head">与旧版页面相比较您觉得新版页面：</div><br>
<?
if(!isset(＄submit)){
?>
<form action="myPolls.php3" method="get">
<input type="radio" name="poll_voteNr" value="1" checked >
<span class="pt9">信息量更大</span> <br>
<input type="radio" name="poll_voteNr" value="2" >
<span class="pt9">网页更精美</span> <br>
<input type="radio" name="poll_voteNr" value="3" >
<span class="pt9">没什么改进</span> <br>
<input type="radio" name="poll_voteNr" value="4" >
<span class="pt9">其它</span> <br>
<input type="submit" name="submit" value="OK">
<input type="hidden" name="poll" value="vote">
<A HREF="myPolls.php3?submit=OK" class="p9">查看调查结果</A>
</form>
<?
/*
如果想增加其它的选项可直接加上即可
*/
}else{
＄descArray=array(1=>"信息量更大",
2=>"网页更精美",
3=>"没什么改进",
4=>"其它"
);
＄poll_resultBarHeight = 9; // height in pixels of percentage bar in result table
＄poll_resultBarScale = 1; // scale of result bar (in multiples of 100 pixels)
＄poll_tableHeader="<table border=1 class="tb">";
＄poll_rowHeader="<tr>";
＄poll_dataHeader="<td align=center>";
＄poll_dataFooter="</td>";
＄poll_rowFooter="</tr>";
＄poll_tableFooter="</table>";
＄coutfile="data.pol";
＄poll_sum=0;
// read counter-file
if (file_exists( ＄coutfile))
{
＄fp = fopen( ＄coutfile, "rt");
while (＄Line = fgets(＄fp, 10))
{
// split lines into identifier/counter
if (ereg( "([^ ]*) *([0-9]*)", ＄Line, ＄tmp))
{
＄curArray[(int)＄tmp[1]] = (int)＄tmp[2];
＄poll_sum+=(int)＄tmp[2];
}
}
// close file
fclose(＄fp);
}else{//
for (＄i=1;＄i<=count(＄descArray);＄i++){
＄curArray[＄i]=0;
}
}
if(isset(＄poll)){
＄curArray[＄poll_voteNr]++;
＄poll_sum++;
}
echo ＄poll_tableHeader;
// cycle through all options编历数组
reset(＄curArray);
while (list(＄K, ＄V) = each(＄curArray))
{
＄poll_optionText = ＄descArray[＄K];
＄poll_optionCount = ＄V;
echo ＄poll_rowHeader;
if(＄poll_optionText != "")
{
echo ＄poll_dataHeader;
echo ＄poll_optionText;
echo ＄poll_dataFooter;
if(＄poll_sum)
＄poll_percent = 100 * ＄poll_optionCount / ＄poll_sum;
else
＄poll_percent = 0;
echo ＄poll_dataHeader;
if (＄poll_percent > 0)
{
＄poll_percentScale = (int)(＄poll_percent * ＄poll_resultBarScale);
}
printf(" %.2f %% (%d)", ＄poll_percent, ＄poll_optionCount);
echo ＄poll_dataFooter;
}
echo ＄poll_rowFooter;
}
echo "总共投票次数:<font color=red> ＄poll_sum</font>";
echo ＄poll_tableFooter;
echo "<br>";
echo "<input type="submit" name="Submit1" value="返回主页" onClick="javascript:location='http://gophp.heha.net/index.html'">";
echo " <input type="submit" name="Submit2" value="重新投票" onClick="javascript:location='http://gophp.heha.net/mypolls.php3'">";
if(isset(＄poll)){
// write counter file
＄fp = fopen(＄coutfile, "wt");
reset(＄curArray);
while (list(＄Key, ＄Value) = each(＄curArray))
{
＄tmp = sprintf( "%s %dn", ＄Key, ＄Value);
fwrite(＄fp, ＄tmp);
}
// close file
fclose(＄fp);
}
}
?>
</body>
</html>
注释：从上面我们可以看出该投票系统的基本过程：
1、打开文件取得数据到数组＄curArray（文件不存在则初始化数组＄curArray）
2、编历数组，处理数据得到所需值
3、计算百分比，控制统计bar图像宽度
4、将数据保存到"data.pol"中
这里有一点是需要注意：这里的data.pol文本文件需要有写权限。
原作者：Hunte
来源：PHPUser
