我有这个代码：
<?php
echo $_POST['id-input'];
$time = time();
$ip=$_SERVER['REMOTE_ADDR'];
$userid_c = $_POST['id-input'];
$con = mysql_connect("localhost","username","password");
if (!$con)
{
die('Could not connect: ' . mysql_error());
}
mysql_select_db("kritya20_data", $con);
$sql = "SELECT * FROM users_online WHERE user_id='$userid_c'";
$query = mysql_query($sql);
$rows_only_c = mysql_num_rows($query);
if($rows_only_c == 0)
{
$sql1= "INSERT INTO users_online (user_id , online_since , lastup , lobbieid)
VALUES ('$userid_c' , '$time' , '$time' , '1')";
$query1 = mysql_query($sql1);
}
elseif($rows_only_c==1)
{
$sql2 = "UPDATE users_online
SET lastup='$time'
WHERE user_id='$userid_c' ";
$query2 = mysql_query($sql2);
}
$sql3 = "SELECT * FROM iptable WHERE user_id='$userid_c'";
$query3 = mysql_query($sql3);
$row_ip = mysql_num_rows($query3);
if($row_ip==0)
{
$sql4 = "INSERT INTO iptable (user_id , ip , added)
VALUES ('$userid_c' , '$ip' , '$time')";
$query4= mysql_query($sql4);
}
elseif($row_ip>0)
{
$mt=0;
$mf=0;
$sql4 = "SELECT * FROM iptable WHERE user_id='$userid_c'";
$query4 = mysql_query($sql4);
while($row=$query4)
{
if($ip==$row[2])
{
$mt++;
}
else
{
$mf++;
}
}
if($mf!=0)
{
$sql5 = "INSERT INTO iptable (user_id , ip , added)
VALUES ('$userid_c' , '$ip' , '$time')";
$query5= mysql_query($sql5);
}
}
?>
我哪里出错了O因为要么它只是第一次添加，要么每当ip更改时都不会添加。
我修改了下面的代码，以改进布局、描述性变量名称、添加调试、建议的逻辑改进，这些改进简化了代码并修复了您的错误。
请阅读并尝试在未来的代码中使用其中的一些内容，它将极大地帮助您调试或编写人们能够理解的代码。我不想听起来像个屈尊俯就的混蛋，我们都是从某个地方开始的，我仍然会犯愚蠢的错误！
如果我做了什么你不明白（或者代码，或者我为什么这么做），请问。
<?php
$debug_on = true;
#Variable section
$time = time();
$ip=$_SERVER['REMOTE_ADDR'];
$userid_c = $_POST['id-input'];
if($debug_on) {
echo "<p>time: '$time'</p>";
echo "<p>ip: '$ip'</p>";
echo "<p>userid_c: '$userid_c'</p>";
}
#Connect to database
$con = mysql_connect("localhost","username","password");
if (!$con) {
die('Could not connect: ' . mysql_error());
}
mysql_select_db("kritya20_data", $con) or die('Could not select database');
#Insert or update users_online
$user_exits_sql = "SELECT * FROM users_online WHERE user_id='$userid_c'";
$user_exits_query = mysql_query($user_exits_sql);
$user_exists = mysql_num_rows($user_exits_query);
if($user_exists == 0) {
$insert_user_sql = "INSERT INTO users_online (user_id , online_since , lastup , lobbieid) VALUES ('$userid_c' , '$time' , '$time' , '1')";
if($debug_on) {
echo "<p>No record found in `users_online` - Inserting new record</p>";
echo "<p>$insert_user_sql</p>";
}
mysql_query($insert_user_sql);
}
else { # no need for 'elseif($rows_only_c==1)' as this is the only other option
$update_user_sql = "UPDATE users_online
SET lastup='$time'
WHERE user_id='$userid_c' ";
if($debug_on) {
echo "<p>Record found in `users_online` - Updating existing record</p>";
echo "<p>$update_user_sql</p>";
}
mysql_query($update_user_sql);
}
#Insert or update iptable
$user_ip_exists_sql = "SELECT * FROM iptable WHERE user_id='$userid_c'";
$user_ip_exists_query = mysql_query($user_ip_exists_sql);
$user_ip_exists = mysql_num_rows($user_ip_exists_query);
if($user_ip_exists==0) {
$user_ip_insert_sql = "INSERT INTO iptable (user_id , ip , added)
VALUES ('$userid_c' , '$ip' , '$time')";
if($debug_on) {
echo "<p>No record found in `iptable` - Inserting new record</p>";
echo "<p>$user_ip_insert_sql</p>";
}
mysql_query($user_ip_insert_sql);
}
else { # 'elseif($row_ip>0)'
$mt = 0;
$mf = 0;
$iptable_sql = "SELECT * FROM iptable WHERE user_id='$userid_c'";
$iptable_query = mysql_query($iptable_sql);
#The next line is your bug,
#should read while($row = $iptable_query->mysql_fetch_array())
while($row = $iptable_query) {
if($ip==$row[2]) {
$mt++;
}
else {
$mf++;
}
}
# For bonus points you could use $iptable_query->mysql_fetch_row(), then $row->ip rather than $row[2].
# This makes it obvious what variable you are trying to access.
if($mf != 0) {
$iptable_insert_sql = "INSERT INTO iptable (user_id , ip , added)
VALUES ('$userid_c' , '$ip' , '$time')";
if($debug_on) {
echo "<p>No record found in `iptable` for user with this ip address - Inserting new record</p>";
echo "<p>$iptable_insert_sql</p>";
}
mysql_query($iptable_insert_sql);
}
# This whole section seems to be:
# If user doesnt exist, add them,
# If user does exist, but not for this ip, add them
# If this is right this could be made much simpler by changing $user_ip_exists_sql to be where user_id='$userid_c' and ip='$ip'
# then you could remove all the $mt, $mf stuff
}
?>
代码可能会有一些改进。但是，尝试将while($row=$query4)更改为while($row=mysql_fetch_array($query4))
同样，由于您要运行$sql3 = "SELECT * FROM iptable WHERE user_id='$userid_c'";两次，为什么不直接使用第一个查询的结果集，而不是向数据库发送另一个查询呢。