文件上传学习

单文件上传

1. 表单上传

    <form action="" method="post" enctype="multipart/form-data">
        <fieldset>
            <legend>单文件上传</legend>
            <!-- 前端设置上传文件的大小：字节 -->
            <!-- <input type="hidden" name="MAX_FILE_SIZE" value="5600"> -->
            <input type="file" name="my_pic" id="">
            <button>上传</button>
        </fieldset>
    </form>

2. 查看上传信息

   // $_FILES: 文件上传变量,超全局的变量数组, 保存着所有与文件上传的相关信息
   printf('<pre>%s</pre>', print_r($_FILES, true));

   
   

自定义异常类

1. 自定义文件上传的异常类

   // 自定义文件上传的异类处理类
   class UploadException extends Exception
   {
    public function __toString()
    {
        return <<<UPLOAD
        <table>
            <tr>
                <td>编号</td>
                <td>信息</td>
                <td>文件</td>
                <td>行号</td>
            </tr>
            <tr>
                <td>$this->code</td>
                <td>$this->message</td>
                <td>$this->file</td>
                <td>$this->line</td>
            </tr>
        </table>
        <style>
        table {border-collapse: collapse;border:1px solid black;text-align: center;}
        td {border:1px solid black;padding: 5px;}
        tr:first-of-type {background-color:#eee;}
        tr:last-of-type td {color: red;}
        </style>
        UPLOAD;
    }
   }

2. 调用异常类

    try
    {
        // 1.对错误代码的判断
        $errorCode = $_FILES['my_pic']['error'] ?? null;
        // 使用系统常量进行判断
        if($errorCode>UPLOAD_ERR_OK){
            switch ($errorCode){
                case UPLOAD_ERR_INI_SIZE:
                    throw new UploadException('上传的文件超过了php.ini 中 upload_max_filesize 选项限制的值',1);
                break;
                case UPLOAD_ERR_FORM_SIZE:
                    throw new UploadException('上传的文件超出了表单中设置的大小',2);
                break;
                case UPLOAD_ERR_PARTIAL:
                    throw new UploadException('文件只有部分被上传', 3);
                    break;
                case UPLOAD_ERR_NO_FILE:
                    throw new UploadException('没有文件被上传', 4);
                    break;
                case UPLOAD_ERR_NO_TMP_DIR:
                    throw new UploadException('找不到临时文件夹', 5);
                    break;
                case UPLOAD_ERR_CANT_WRITE:
                    throw new UploadException('文件写入失败', 6);
                    break;
                default:
                    // 测试时建议关掉default: 避免误报影响
                    throw new UploadException('未知类型错误', 7);
            }
        }
        // 2.判断文件类型是否正确
        $fileType = $_FILES['my_pic']['type'] ?? null;
        $type = strstr($fileType,'/',true);
        if(!is_null($fileType)){
            if($type!=='image') throw new UploadException('上传类型错误',8);
        }
    }catch(UploadException $e){
        echo $e;
    }

   
   
   

3. 单文件（图片上传）

• 先准备一个存放上传文件的文件

• 把临时文件上传到目标目录

    // 判断上传方式是否正确?
    // 临时文件名
    $tmplFileName = $_FILES['my_pic']['tmp_name']  ?? null;
    // 1. 首先临时文件是存在的,并且必须是通过POST上传的
    if ($tmplFileName && is_uploaded_file($tmplFileName)) {
        // 2. 将文件从临时目录移动到目标目录中: uploads/
        // move_uploaded_file(临时文件, 目标文件名)
        // 原始文件名
        $originalFileName =  $_FILES['my_pic']['name'] ?? null;
        echo strstr($originalFileName, '.');
        // 目标文件名
        $destFileName = 'uploads/' . md5(time(). mt_rand(1,1000))  .strstr($originalFileName, '.');
        if (move_uploaded_file($tmplFileName, $destFileName)) {
            echo '<p>'. $_FILES['my_pic']['name'].': 上传成功</p>';
            // 预览图片
            echo "<img src='{$destFileName}' width='200'>";
        }
    }

多文件上传

1. 文件批量上传中缺失的异常处理, 文件类型处理等操作

    <form action="" method="post" enctype="multipart/form-data">
        <fieldset>
            <legend>批量上传文件</legend>
            <input type="file" name="my_pic1" id="">
            <input type="file" name="my_pic2" id="">
            <input type="file" name="my_pic3" id="">
            <button>上传</button>
        </fieldset>
    </form>

   foreach ($_FILES as $k=>$file) {
    // echo $k;
    try
    {
            // 1.对错误代码的判断
            $errorCode = $_FILES[$k]['error'] ?? null;
            // 使用系统常量进行判断
            if($errorCode>UPLOAD_ERR_OK){
                switch ($errorCode){
                    case UPLOAD_ERR_INI_SIZE:
                        throw new UploadException('上传的文件超过了php.ini 中 upload_max_filesize 选项限制的值',1);
                    break;
                    case UPLOAD_ERR_FORM_SIZE:
                        throw new UploadException('上传的文件超出了表单中设置的大小',2);
                    break;
                    case UPLOAD_ERR_PARTIAL:
                        throw new UploadException('文件只有部分被上传', 3);
                        break;
                    case UPLOAD_ERR_NO_FILE:
                        throw new UploadException('没有文件被上传', 4);
                        break;
                    case UPLOAD_ERR_NO_TMP_DIR:
                        throw new UploadException('找不到临时文件夹', 5);
                        break;
                    case UPLOAD_ERR_CANT_WRITE:
                        throw new UploadException('文件写入失败', 6);
                        break;
                    default:
                        // 测试时建议关掉default: 避免误报影响
                        throw new UploadException('未知类型错误', 7);
                }
            }
            // 2.判断文件类型是否正确
            $fileType = $_FILES[$k]['type'] ?? null;
            $type = strstr($fileType,'/',true);
            if(!is_null($fileType)){
                if($type!=='image') throw new UploadException('上传类型错误',8);
            }
    }catch(UploadException $e){
        echo $e;
    }
   }

   

2. 文件批量上传

            if($file['error']===0){
                $destFileName = 'uploads/' . md5(time().mt_rand(1,1000)) . strstr($file['name'],'.');
                if(move_uploaded_file($file['tmp_name'],$destFileName)){
                    echo $file['name'].':上传成功!'.'<hr>';
                    // 预览图片
                    echo "<img src='{$destFileName}' width='200'>";
                }
            }

   
   

*封装一个文件上传类,可同时处理单文件与多文件上传(还在进一步学习)