Question

如果有数据，第一部分效果很好。当没有$ res时，else部分不回显。

IO尝试过使用这个但是！ $ row停止并且不会回显内部的任何内容。所以我把它改写成下面的PHP脚本，这更直接。我现在担心sql注入因为我正在清理id以及验证用户实际登录到系统。

$stmt = $conn->prepare('SELECT * FROM table WHERE ID=?');
$stmt->bindParam(1, $_GET['id'], PDO::PARAM_INT);
$stmt->execute();
$row = $stmt->fetch(PDO::FETCH_ASSOC);

if( ! $row)
{
    die('nothing found');
}else { 
enter code here
}

Thjs是我的整个php页面。

$ db = new PDO（连接字符串。）

            <?php
            error_reporting(0);
            include_once("php_includes/db_conx.php");
            if($_GET['id'] != ''){
                $id = preg_replace('#[^0-9]#', '', $_GET['id']);
                $sql="SELECT nextdue, alert, completed, page_id, page_type FROM medical where id=$id limit 1";
                        $alertdiv = "";
                if ($res = $db->query($sql)) {

                            $alertdiv = "";
                        foreach( $db->query($sql) as $data ) {              
                            //if alert is set to Y create div to show the type and stuff. 
                            $timestamp = $data[0];
                            if ($data[1]=='y'){
                                if($timestamp > date("Y-m-d")) {
                                $alertdiv .= "This alert is in the Future.<br>";
                            }
                            if($timestamp < date("Y-m-d")) {
                                  $alertdiv .= "This alert is pastdue.<br>";
                            }
                            if($timestamp == date("Y-m-d")) {
                                  $alertdiv .= "This alert is due Today.<br>";
                            }
                            $alertdiv .= "<table><tr><td width='50'>Method</td><td>Description</td><td>Destination</td><td>Completed</td><td>Date Due</td><td>Action</td></tr><br>";    

                            $completed = $data[2];
                            $page_id = $data[3];
                            $page_type = $data[4];
                                //check completed

                                //get page details 
                                switch ($page_type) {
                                       case "d":
                                        $alertdiv .= "<tr id='selectedmethodtr' value='d0'>";
                                             $alertdiv .= "<td width='10'>Default</td><td>Dashboard</td><td>Dashboard</td>";
                                             break;
                                       case "e":
                                        $alertdiv .= "<tr  id='selectedmethodtr' value='e$data[3]'>";
                                             $sql1 = "SELECT description, email from page_email where page_email_id=$page_id";
                                                foreach( $db->query($sql1) as $data1 ) {    
                                                    $alertdiv .= "<td width='50'>E-Mail</td><td>$data1[0]</td><td>$data1[1]</td>";
                                        }   

                                             break;
                                       case "p":
                                        $alertdiv .= "<tr  id='selectedmethodtr' value='p$data[3]'>";
                                              $sql1 = "SELECT description, phone, carriervalue from page_phone where page_phone_id=$page_id";
                                                foreach( $db->query($sql1) as $data1 ) {    
                                                    $alertdiv .= "<td width='50' >E-Mail</td><td>$data1[0]</td><td>$data1[1]</td>";
                                        }   
                                             break;
                                    }

                                    switch ($completed) {
                                       case "0":
                                             $alertdiv .= "<td>No</td>";
                                             break;
                                       case "1":
                                             $alertdiv .= "<td>Yes</td>";
                                             break;

                                    }
                                $alertdiv .= "<td>$timestamp</td>";
                             $alertdiv .= "<td><a onClick=deleteAlert($id) id='deleteAlert'><i class='fa fa-trash-o fa-lg'></i></a></td></tr>";
                        }
                    }//end if data[1]
                $alertdiv .= "</table>";
                 echo $alertdiv;
                    }else {
                        $alertdiv .= "Alert Type is set Default Dashboard! <br>";
                        $alertdiv .= "<table id='selectedmethodtable'>";
                        $alertdiv .= "<tr>";
                        $alertdiv .= "<td>Description</td>";
                        $alertdiv .= "<td >Method</td><option id='selectedmethodtr' value='d0' ></option>";
                        $alertdiv .= "</tr>";
                        $alertdiv .= "<tr ><td>DashBoard</td><td>Default</td></tr>";
                        $alertdiv .= "</table>";
                         echo $alertdiv;
                    }

            }
            ?>

Answer 1

您的评论（“找到的结果”）是错误的。

我假设$db->query是mysqli's query method。

失败时返回FALSE。对于成功的SELECT，SHOW，DESCRIBE或EXPLAIN查询，mysqli_query（）将返回一个mysqli_result对象。对于其他成功的查询，mysqli_query（）将返回TRUE。

如果查询成功运行，则该值为true，即使该查询未找到匹配的行。

如果运行查询的错误，您将收到错误的结果。

要测试是否没有结果，您应该使用num_rows。

if ($res = $db->query($sql)) { // Query ran without errors
    if ($res->num_rows == 0) {
        // There were no results found
    } else {
        while($row = $res->fetch_assoc($result)) {
           // Do stuff with the data in the `$row`
        }
    }
} else {
    // There was an error running the query
}

如果没有找到resuts，则回显mysql

1 个答案: