Php 如何查询数据库中的IP错误

我正在努力做到，如果他们的IP在数据库中，那么他们就不能发送电子邮件。在php54_错误文件中，它说

[30-Dec-2012 18:25:26 Europe/Dublin] PHP Warning:  mysql_num_rows() expects parameter 1 to be resource, string given in C:\inetpub\wwwroot\Submit.php on line 6
[30-Dec-2012 18:25:26 Europe/Dublin] PHP Warning:  mysql_num_rows() expects parameter 1 to be resource, null given in C:\inetpub\wwwroot\Submit.php on line 7

我的PHP代码如下

<?php
include("connect.php");
mysql_select_db("ip", $con);
$ip = mysql_real_escape_string($_SERVER['REMOTE_ADDR']);
$query = "SELECT * FROM ip WHERE ip='$ip'";
$result = mysql_num_rows($query);
if (mysql_num_rows($result) > 0) {
    echo "You have already registered!";
}
else { 
    echo"Your request has been sent!";
    $to = "admin@prisoneternity.org.uk";
    $subject = "Guard Application";
    $from = "guardapplication@prisoneternity.org.uk";
    $headers = "From:" . $from;
    $message = "IGN = " . $_POST["Username"] . "</br>\n\nage = " . $_POST["age"] . "</br>\n\nreason = " . $_POST["reason"] . "</br>\n\nHow many times have they been guard = " . $_POST["guard"] . "</br>\n\nOther Details = " . $_POST["text"];
    mail($to,$subject,$message,$headers);
    header ("Location: index.php?email=yes");
    session_start();
    mysql_query("INSERT INTO ip (IP) VALUES ('$ip')");
}
?>

---

在第二行，
mysql\u num\u rows
正在返回一个整数，因为
$result
变量已经在调用该函数了（如果有意义的话）。将其更改为：

$result = mysql_num_rows($query);
if ($result > 0) {

此外，您没有运行查询：

$query = "SELECT * FROM ip WHERE ip='$ip'";

将上述行更改为：

$query = mysql_query("SELECT * FROM ip WHERE ip='$ip'");



另一方面，
mysql.*
函数已被弃用。我将切换到
PDO
或
MySQLi
——示例可以在中找到

应该是：

$result = mysql_query($query);
if (mysql_num_rows($result) > 0) {

您没有运行
mysql\u query（）
，而是调用了
mysql\u num\u rows（）
两次。简单事故=o）顺便说一句，您应该使用或

此外：

echo“您的请求已发送！”；
$to=”admin@prisoneternity.org.uk";
$subject=“警卫应用程序”；
$from=”guardapplication@prisoneternity.org.uk";
$headers=“From:”$从…起
$message=“IGN=”$_发布[“用户名”]。“
\n\nage=“$_职位[“年龄”]。“
\n\n原因=”$_张贴[“原因”]。“
\n\n他们被保护了多少次？”$_立柱[“防护”]。“
\n\n其他详细信息=”$_POST[“text”]；
邮件（$to、$subject、$message、$headers）；
标题（“Location:index.php？email=yes”）；
会话_start（）；
mysql_查询（“插入ip（ip）值（“$ip”）”；

应该是：

$to = "admin@prisoneternity.org.uk";
$subject = "Guard Application";
$from = "guardapplication@prisoneternity.org.uk";
$headers = "From:" . $from;
$message = "IGN = " . $_POST["Username"] . "</br>\n\nage = " . $_POST["age"] . "</br>\n\nreason = " . $_POST["reason"] . "</br>\n\nHow many times have they been guard = " . $_POST["guard"] . "</br>\n\nOther Details = " . $_POST["text"];
mail($to,$subject,$message,$headers);
//header ("Location: index.php?email=yes");
session_start();
echo"Your request has been sent!";
mysql_query("INSERT INTO ip (IP) VALUES ('$ip')");

$to=”admin@prisoneternity.org.uk";
$subject=“警卫应用程序”；
$from=”guardapplication@prisoneternity.org.uk";
$headers=“From:”$从…起
$message=“IGN=”$_发布[“用户名”]。“
\n\nage=“$_职位[“年龄”]。“
\n\n原因=”$_张贴[“原因”]。“
\n\n他们被保护了多少次？”$_立柱[“防护”]。“
\n\n其他详细信息=”$_POST[“text”]；
邮件（$to、$subject、$message、$headers）；
//标题（“Location:index.php？email=yes”）；
会话_start（）；
回显“您的请求已发送！”；
mysql_查询（“插入ip（ip）值（“$ip”）”；

您不能回显
标题（）
或
会话启动（）
之前的内容，而且在执行重定向时，回显的文本也不会被看到。你需要选择你想做的事情。我注释掉了上面的
标题（）
，但您可以做相反的事情。另外，请确保对
\r
和
\n
字符的所有
$\u POST
值进行清理，以防止出现问题。
没问题！很高兴我能帮忙。：）
echo"Your request has been sent!";
$to = "admin@prisoneternity.org.uk";
$subject = "Guard Application";
$from = "guardapplication@prisoneternity.org.uk";
$headers = "From:" . $from;
$message = "IGN = " . $_POST["Username"] . "</br>\n\nage = " . $_POST["age"] . "</br>\n\nreason = " . $_POST["reason"] . "</br>\n\nHow many times have they been guard = " . $_POST["guard"] . "</br>\n\nOther Details = " . $_POST["text"];
mail($to,$subject,$message,$headers);
header ("Location: index.php?email=yes");
session_start();
mysql_query("INSERT INTO ip (IP) VALUES ('$ip')");

$to = "admin@prisoneternity.org.uk";
$subject = "Guard Application";
$from = "guardapplication@prisoneternity.org.uk";
$headers = "From:" . $from;
$message = "IGN = " . $_POST["Username"] . "</br>\n\nage = " . $_POST["age"] . "</br>\n\nreason = " . $_POST["reason"] . "</br>\n\nHow many times have they been guard = " . $_POST["guard"] . "</br>\n\nOther Details = " . $_POST["text"];
mail($to,$subject,$message,$headers);
//header ("Location: index.php?email=yes");
session_start();
echo"Your request has been sent!";
mysql_query("INSERT INTO ip (IP) VALUES ('$ip')");