使用php echo语句下载文件

我的项目有问题。我有两个名为index.php和download.php的文件，其中index.php动态显示了表中的一些内容，所以我想下载像joe.pdf这样的表内容，因为我将单击我的链接，但我编写的代码显示了一些问题，比如无效文件，我想我在filedownloading echo语句中遗漏了一些内容

因此，我在此附上两个文件：

index.php

<?php
    // Establish Connection with Database
    $con = mysql_connect("localhost","root");

    // Select Database
    mysql_select_db("cms", $con);

    // Specify the query to execute
    $sql = "select * from user_tbl where approval='0'";

    // Execute query
    $result = mysql_query($sql,$con);

    $i = 1;

    //echo "<form action='process.php' method='post'>"; 
    echo "<table border='.025'>
    <tr>
    <th>UID</th>
    <th>Name</th>
    <th>Address</th>
    <th>City</th>
    <th>Mobile</th>
    <th>Email</th>
    <th>gender</th>
    <th>BirthDate</th>
    <th>Username</th>
    <th>Password</th>
    <th>Station-Name</th>
    <th>Verification Proof</th>
    <th>Approve</th>
    </tr>";

    while($row = mysql_fetch_array($result)) {
        echo "<tr>";
        echo "<td>" . $row['User_Id'] . "</td>";
        echo "<td>" . $row['Name'] . "</td>";
        echo "<td>" . $row['Address'] . "</td>";
        echo "<td>" . $row['City'] . "</td>";
        echo "<td>" . $row['Mobile'] . "</td>";
        echo "<td>" . $row['Email'] . "</td>";
        echo "<td>" . $row['Gender'] . "</td>";
        echo "<td>" . $row['BirthDate'] . "</td>";
        echo "<td>" . $row['UserName'] . "</td>";
        echo "<td>" . $row['Password'] . "</td>";
        echo "<td>" . $row['Station_Name'] . "</td>";
        //echo "<td>" . $row['VerificationProof'] . "</td>";
        $name=$row['VerificationProof'];enter code here
        echo "<td><a href='download.php?filename=$name'>$name</a></td>"; 
        echo "<td><input type='checkbox' name='check[$i]' value='".$row['User_Id']."'/>";   
        echo "</tr>";
        $i++;
    }
    echo "</table>";
?>
<br>
</br>
<?php 
    echo "<input type='submit' name='approve' value='approve'/>";
    echo "</form>";
    mysql_close($con);
?>

---

出现了什么错误？为什么要注释
//echo“”您的代码中有很多错误。例如：
$name=$row['VerificationProof']；在此处输入代码
您应该使用锚链接将请求参数从index.php传递到download.php，或者使用表单。您在代码中留下了表单结束标记，在这种情况下，提交按钮甚至是不必要的。先生，我有一个这样的HTML语句，我想使用echo将其转换为相应的php语句，我尝试了如下echo“”；但是缺少了一些东西，所以它显示了一些错误，所以请帮助我如何将下面给出的html语句转换为php语句
<?php
    function output_file($file, $mime_type='') {
        if(!is_readable($file)) die('File not found or inaccessible!');

        $size = filesize($file);
        $name = rawurldecode($name);
        $known_mime_types=array(
            "pdf" => "application/pdf",
            "txt" => "text/plain",
            "html" => "text/html",
            "htm" => "text/html",
            "exe" => "application/octet-stream",
            "zip" => "application/zip",
            "doc" => "application/msword",
            "xls" => "application/vnd.ms-excel",
            "ppt" => "application/vnd.ms-powerpoint",
            "gif" => "image/gif",
            "png" => "image/png",
            "jpeg"=> "image/jpg",
            "jpg" => "image/jpg",
            "php" => "text/plain"
        );
        if($mime_type=='') {
            $file_extension = strtolower(substr(strrchr($file,"."),1));
            if(array_key_exists($file_extension, $known_mime_types)) {
                $mime_type=$known_mime_types[$file_extension];
            } else {
                $mime_type="app`enter code here`lication/force-download";
            };
        };

        @ob_end_clean();

        if(ini_get('zlib.output_compression'))
            ini_set('zlib.output_compression', 'Off');
        header('Content-Type: ' . $mime_type);
        header('Content-Disposition: attachment; filename="'.$name.'"');
        header("Content-Transfer-Encoding: binary");
        header('Accept-Ranges: bytes');
        header("Cache-control: private");
        header('Pragma: private');
        header("Expires: Mon, 26 Jul 1997 05:00:00 GMT");
        if(isset($_SERVER['HTTP_RANGE'])) {
            list($a, $range) = explode("=",$_SERVER['HTTP_RANGE'],2);
            list($range) = explode(",",$range,2);
            list($range, $range_end) = explode("-", $range);
            $range=intval($range);
            if(!$range_end) {
                $range_end=$size-1;
            } else {
                $range_end=intval($range_end);
            }
            $new_length = $range_end-$range+1;
            header("HTTP/1.1 206 Partial Content");
            header("Content-Length: $new_length");
            header("Content-Range: bytes $range-$range_end/$size");
        } else {
            $new_length=$size;
            header("Content-Length: ".$size);
        }
        $chunksize = 1*(1024*1024);
        $bytes_send = 0;
        if ($file = fopen($file, 'r')) {
            if(isset($_SERVER['HTTP_RANGE']))
                fseek($file, $range);
            while(!feof($file) && (!connection_aborted()) && ($bytes_send<$new_length)) {
                $buffer = fread($file, $chunksize);
                print($buffer);
                flush();
                $bytes_send += strlen($buffer);
            }
            fclose($file);
        } else
            die('Error - can not open file.');
        die();
    }
    set_time_limit(0);
    $file_path='Documents/'.$_REQUEST['filename'];
    output_file($file_path, ''.$_REQUEST['filename'].'', 'text/plain');
?>