Question

我现在遇到了最棘手的问题。为了查看联系人是否已经在数据库中，我检查它。让我看到我回应：“在数据库中”或“不在数据库中”。为了让用户看到我用同样的按摩给他回来了。奇怪的是，echo始终是正确的，但字符串总是相同的“不在数据库中”，即使联系人在数据库中也是如此。例如：我加我的妈妈。我的妈妈在数据库中，所以回声是正确的，并说“在数据库中”。但我收到的字符串总是说“不在数据库中”。

完整代码

<?php
    $DB_HostName = "localhost";
    $DB_Name = "db";
    $DB_User = "user";
    $DB_Pass = "pw";
    $DB_Table = "contacts";

    $con = mysql_connect($DB_HostName,$DB_User,$DB_Pass) or die (mysql_error()); 
    mysql_select_db($DB_Name,$con) or die(mysql_error()); 

    $fnumber = mysql_real_escape_string($_GET["fnumber"]);

    $result = mysql_query("SELECT * FROM $DB_Table WHERE User = '$fnumber'", $con);

    if ($result) {

        if (mysql_num_rows($result) > 0) {

            echo "This user is already in database";

            $number = mysql_real_escape_string($_GET["number"]);

            mysql_query("DELETE FROM Echo WHERE Number=('$number')");

            mysql_query("INSERT INTO Echo (Number,Answer)
            VALUES ('$number','This user is already in database.')");
        }

        else echo 
            "This user isn't in the database";

        $number = mysql_real_escape_string($_GET["number"]);

        mysql_query("DELETE FROM Echo WHERE Number=('$number')");

        mysql_query("INSERT INTO Echo (Number,Answer)
        VALUES ('$number','this user isn't in the database.')");
    }

    mysql_close($con);
?>

在您提出之前：为了不占用我的数据库，我总是删除该号码，然后写入该条目。

Answer 1

我想这是正确的代码：

if ($result) {

    if (mysql_num_rows($result) > 0) {

        echo "This user is already in database";

        $number = mysql_real_escape_string($_GET["number"]);

        mysql_query("DELETE FROM Echo WHERE Number=('$number')");

        mysql_query("INSERT INTO Echo (Number,Answer)
        VALUES ('$number','This user is already in database.')");

    } else {

            echo "This user isn't in the database";

        $number = mysql_real_escape_string($_GET["number"]);

        mysql_query("DELETE FROM Echo WHERE Number=('$number')");

        mysql_query("INSERT INTO Echo (Number,Answer)
        VALUES ('$number','this user isn't in the database.')");
    }
}

Answer 2

在

之前需要第二次关闭}

else echo "This user isn't in the database";

Answer 3

else echo 
"This user isn't in the database";

$number = mysql_real_escape_string($_GET["number"]);

mysql_query("DELETE FROM Echo WHERE Number=('$number')");

mysql_query("INSERT INTO Echo (Number,Answer)
VALUES ('$number','this user isn't in the database.')");

由于else之后没有括号，因此将始终执行较低的三行。第二个mysql_query将始终失败，因为'未转义。

Answer 4

您没有将整个else分支括在括号中。那样，`else echo'之后的所有内容这个用户不在数据库“;”中执行时会覆盖您的上述数据。

else分支应如下所示：

    else
    {  // <-- NEW
        echo "This user isn't in the database";

        $number = mysql_real_escape_string($_GET["number"]);

        mysql_query("DELETE FROM Echo WHERE Number=('$number')");

        mysql_query("INSERT INTO Echo (Number,Answer)
        VALUES ('$number','this user isn't in the database.')");
    }  // <-- NEW
}

PHP文件返回正确的echo，但在数据库中写入错误的字符串

4 个答案: