Question

我正在开发一个在线测验系统。

在管理面板上，我有一个标有“添加问题”的按钮。当我点击按钮时，模态对话框打开一个测验表格，其中包含问题句子（3），问题图像（4），将要添加问题的考试（1），难度级别（1到5）（2），五个应答选项（5）和两个单选按钮（6），它们将被启用或禁用。

Modal dialog

这里一切都很好。

这是添加问题模态内容

<?php
include_once '../config.php'; //includes class ExamConfig

$cfg = new ExamConfig();

$examsQuery = $cfg->db->query('SELECT id, exam FROM examinations');

$rowExams = $examsQuery->fetchAll(PDO::FETCH_ASSOC);


$diffQuery = $cfg->db->query('SELECT id, difficulty FROM DifficultyLevels');

$rowDiff = $diffQuery->fetchAll(PDO::FETCH_ASSOC);
?>

<form action="" method="post" class="form-signin" enctype="multipart/form-data" id="frm_addQuestion">
    <p> This question belongs to:
        <select name = "exam" id = "exam" class = "form-control">
            <?php
            foreach ($rowExams as $re)
            {
                echo '<option value="' . $re['id'] . '">' . $re['exam'] . '</option>';
            }
            ?>

        </select>
    </p>
    <p> Question Difficulty Level:
        <select name = "difficulty" id = "difficulty" class = "form-control">
            <?php
            foreach ($rowDiff as $rd)
            {
                echo '<option value="' . $rd['id'] . '">' . $rd['difficulty'] . '</option>';
            }
            ?>

        </select>
    </p>
    <p> Question Text:
        <input class = "form-control" type = "text" name = "question" id = "question" /> </p>
    <p> Question Picture:
        <input type = "file"  name = "qPicture" id = "qPicture" /> </p>
    <p> <strong> Option 1 (Correct Answer): </strong>
        <input class = "form-control success" type = "text" name = "opt1" id = "opt1" /> </p>

    <p> Option 2:
        <input type = "text" class = "form-control" name = "opt2" id = "opt2" /> </p>

    <p> Option 3:
        <input type = "text" class = "form-control" name = "opt3" id = "opt3" /> </p>

    <p> Option 4:
        <input type = "text" class = "form-control" name = "opt4" id = "opt4" /> </p>

    <p> Option 5:
        <input type = "text" class = "form-control" name = "opt5" id = "opt5" /> </p>

    <p> <input type = "radio" name = "enabled" id = "enabled" value = "1" /> Enabled </p>
    <p> <input type = "radio" name = "enabled" id = "enabled" value = "0" /> Disabled </p>
    <p> <a class = "btn btn-primary btn-block" type = "button" name = "btn_question_save" id = "btn_question_save" onclick="SaveQuestion();"> Save Question</a></p>
</form>

这是包含 SaveQuestion（）功能的JS文件：

function SaveQuestion() {

    var request;
    // abort any pending request
    if (request) {
        request.abort();
    }
    // setup some local variables
    var $form = $('#frm_AddQuestion');

    // let's select and cache all the fields
    var $inputs = $form.find("input, select, button");

    // serialize the data in the form
    var serializedData = $form.serialize();

    // let's disable the inputs for the duration of the ajax request
    $inputs.prop("disabled", true);

    // fire off the request to /QuestionSave.php
    request = $.ajax({
    url: "QuestionSave.php",
    type: "post",
    data: serializedData,
    success: function(result)
    {
        response = result;
    }
});

// callback handler that will be called on success
request.done(function(response, textStatus, jqXHR) {
    if (response === "0")
    {
        alert('Hey!'); //record inserted
    }
    else if( response === "900")
    {
        alert('Oh noooo!'); //record not inserted
    }
});

// callback handler that will be called on failure
request.fail(function(jqXHR, textStatus, errorThrown) {
    // log the error to the console
    console.error(
            "Oops: " +
            textStatus, errorThrown
            );
});

// callback handler that will be called regardless
// if the request failed or succeeded
request.always(function() {
    // reenable the inputs
    $inputs.prop("disabled", false);
});
}

最后这是 QuestionSave.php

的代码

<?php    
    if ( !isset( $_SESSION ) )
    {
        session_start();
    }

    include_once '../config.php';
    $cfg = new ExamConfig();

    if ( isset( $_POST ) )
    {

        $imgData = fopen( $_FILES[ 'qPicture' ][ 'tmp_name' ], 'rb' );

        $questionSaveQuery= $cfg->db->prepare( 'INSERT INTO questions (question, user_id, examid, difficultyid, picture, enabled) VALUES( :question, :user_id, :examid, :difficultyid, :picture, :enabled)' );

        $questionSaveQuery->bindValue( ':question', $_POST[ 'question' ], PDO::PARAM_STR );
        $questionSaveQuery->bindValue( ':user_id', $_SESSION[ 'user_id' ], PDO::PARAM_INT );
        $questionSaveQuery->bindValue( ':examid', $_POST[ 'exam' ], PDO::PARAM_INT );
        $questionSaveQuery->bindValue( ':difficultyid', $_POST[ 'difficulty' ], PDO::PARAM_INT );
        $questionSaveQuery->bindValue( ':picture', $imgData, PDO::PARAM_LOB );
        $questionSaveQuery->bindValue( ':enabled', $_POST[ 'enabled' ], PDO::PARAM_INT );

        if ( $questionSaveQuery->execute() )
        {
            $lid = $cfg->db->lastInsertId();

            $optionSaveQuery= $cfg->db->prepare( 'INSERT INTO options
                (questionid, answer, correct) VALUES
                (:qid1, :opt1, 1),
                (:qid2, :opt2, 0),
                (:qid3, :opt3, 0),
                (:qid4, :opt4, 0),
                (:qid5, :opt5, 0)' );

            $optionSaveQuery->bindValue( ':qid1', $lid, PDO::PARAM_INT );
            $optionSaveQuery->bindValue( ':opt1', $_POST[ 'opt1' ], PDO::PARAM_INT );
            $optionSaveQuery->bindValue( ':qid2', $lid, PDO::PARAM_INT );
            $optionSaveQuery->bindValue( ':opt2', $_POST[ 'opt2' ], PDO::PARAM_INT );
            $optionSaveQuery->bindValue( ':qid3', $lid, PDO::PARAM_INT );
            $optionSaveQuery->bindValue( ':opt3', $_POST[ 'opt3' ], PDO::PARAM_INT );
            $optionSaveQuery->bindValue( ':qid4', $lid, PDO::PARAM_INT );
            $optionSaveQuery->bindValue( ':opt4', $_POST[ 'opt4' ], PDO::PARAM_INT );
            $optionSaveQuery->bindValue( ':qid5', $lid, PDO::PARAM_INT );
            $optionSaveQuery->bindValue( ':opt5', $_POST[ 'opt5' ], PDO::PARAM_INT );

            if ( $optionSaveQuery->execute() )
                echo '0';
            else
            {
                echo '901';
                $DeleteLastQuestion = $cfg->db->prepare( 'DELETE FROM questions WHERE id = :id' );
                $DeleteLastQuestion->bindValue( ':id', $lid, PDO::PARAM_INT );
                $DeleteLastQuestion->execute();
            }
        }
        else
            echo '900';
    }
?>

如果我绕过AJAX请求并直接向QuestionSave.php提交表单，则会毫无问题地插入问题。但是，如果我使用Ajax方式，我会收到如下错误：

PHP致命错误：未捕获异常'PDOException'，消息为'SQLSTATE [23000]：完整性约束违规：1048列'图片'不能为空...

换句话说，图片未转移到QuestionSave.php，$_FILES[ 'qPicture' ][ 'tmp_name' ]会返回null。所以它打破了操作。有人建议我摆脱这个问题吗？

图像不是通过jQuery Ajax发布的

0 个答案: