php 对TXT添加修改删除操作

<form method="post">
<input type="text" name="user" />
<input type="text" name="pass" />
<input type="submit" name="Submit" value="提交" />
</form>
<?php
/*写入*/
if ($_POST[Submit]) {
$fp=fopen("db.txt","a");
fwrite($fp,$_POST[user]."|".$_POST[pass]."|".time()."\r\n"); //写入数据，中间用|隔开
fclose($fp);
}
/*读取*/
$lines=file("db.txt");
foreach ($lines as $value) {
$line=explode("|",$value);
echo "no1:$line[0]--no2:$line[1]---time:$line[2]--<a href=gaga.php?act=del&time=$line[2]>删除</a>--<a href=gaga.php?act=mod&time=$line[2]>修改</a><br>";
}
/*删除*/
if ($_GET[act]=="del") {
$time=trim($_GET[time]);
foreach ($lines as $key=>$value) {
$line=explode("|",$value);
if (trim($line[2])==$time) { //遍历数组，定位符合条件的key，并删除改行
unset($lines[$key]);
break;
}
}
unlink("db.txt");
$fp=fopen("db.txt","w");
foreach ($lines as $value) {
fwrite($fp,$value); //写入删除后的新数组
}
fclose($fp);
echo "<script>location.href='gaga.php';</script>";
}
/*修改*/
if ($_GET[act]=="mod") {
$m1="修改值1";
$m2="修改值2";
$m3=time();//修改时间
$time=trim($_GET[time]);
foreach ($lines as $key=>$value) {
$line=explode("|",$value);女装品牌排行榜
if (trim($line[2])==$time) { //遍历数组，定位符合条件的key，并修改改行
$lines[$key]=$m1."|".$m2."|".$m3."\r\n";
break;
}
}
unlink("db.txt");
$fp=fopen("db.txt","w");
foreach ($lines as $value) {
fwrite($fp,$value); //写入修改后的新数组
}
fclose($fp);
echo "<script>location.href='gaga.php';</script>";
}
//print_r("<pre>");
//print_r($lines);
?>