在 PHP 中上传多个文件

Question

我想知道是否有人可以帮助我。

使用一些优秀的在线教程，我整理了下面的代码，该代码允许用户将图像文件上传到服务器文件夹，并将文件名和其他详细信息上传到 mySQL 数据库。

PHP 脚本

<?php
//define a maxim size for the uploaded images
//define ("MAX_SIZE","100"); 
// define the width and height for the thumbnail
// note that theese dimmensions are considered the maximum dimmension and are not fixed, 
// because we have to keep the image ratio intact or it will be deformed
define ("WIDTH","150"); 
define ("HEIGHT","100"); 

// this is the function that will create the thumbnail image from the uploaded image
// the resize will be done considering the width and height defined, but without deforming the image
function make_thumb($img_name,$filename,$new_w,$new_h)
{
//get image extension.
$ext=getExtension($img_name);
//creates the new image using the appropriate function from gd library
if(!strcmp("jpg",$ext) || !strcmp("jpeg",$ext))
$src_img=imagecreatefromjpeg($img_name);

if(!strcmp("png",$ext))
$src_img=imagecreatefrompng($img_name);

//gets the dimmensions of the image
$old_x=imageSX($src_img);
$old_y=imageSY($src_img);

// next we will calculate the new dimmensions for the thumbnail image
// the next steps will be taken: 
// 1. calculate the ratio by dividing the old dimmensions with the new ones
// 2. if the ratio for the width is higher, the width will remain the one define in WIDTH variable
// and the height will be calculated so the image ratio will not change
// 3. otherwise we will use the height ratio for the image
// as a result, only one of the dimmensions will be from the fixed ones
$ratio1=$old_x/$new_w;
$ratio2=$old_y/$new_h;
if($ratio1>$ratio2) {
$thumb_w=$new_w;
$thumb_h=$old_y/$ratio1;
}
else {
$thumb_h=$new_h;
$thumb_w=$old_x/$ratio2;
}

// we create a new image with the new dimmensions
$dst_img=ImageCreateTrueColor($thumb_w,$thumb_h);

// resize the big image to the new created one
imagecopyresampled($dst_img,$src_img,0,0,0,0,$thumb_w,$thumb_h,$old_x,$old_y); 

// output the created image to the file. Now we will have the thumbnail into the file named by $filename
if(!strcmp("png",$ext))
imagepng($dst_img,$filename); 
else
imagejpeg($dst_img,$filename); 

//destroys source and destination images. 
imagedestroy($dst_img); 
imagedestroy($src_img); 
}

// This function reads the extension of the file. 
// It is used to determine if the file is an image by checking the extension. 
function getExtension($str) {
$i = strrpos($str,".");
if (!$i) { return ""; }
$l = strlen($str) - $i;
$ext = substr($str,$i+1,$l);
return $ext;
}
$title = ($_POST['title']); 

if ($title == '') // if title is not set 
$title = '(No Title Provided)';// use (empty title) string 
//reads the name of the file the user submitted for uploading
$image=$_FILES['image']['name'];

if ($image) 
{
// get the original name of the file from the clients machine
$filename = stripslashes($_FILES['image']['name']);

// get the extension of the file in a lower case format
$extension = getExtension($filename);
$extension = strtolower($extension);
// if it is not a known extension, we will suppose it is an error, print an error message 
//and will not upload the file, otherwise we continue
if (($extension != "jpg") && ($extension != "jpeg") && ($extension != "png")) 
{
echo '<b> Error! </b> - The image that you attempted to upload is not in the correct format. The file format <b> must </b> be one of the following: <b> "jpg", "jpeg" </b> or <b> "png" </b>. Please try again.';
$errors=1;
}
else
{
// get the size of the image in bytes
// $_FILES[\'image\'][\'tmp_name\'] is the temporary filename of the file in which the uploaded file was stored on the server
$size=getimagesize($_FILES['image']['tmp_name']);
$sizekb=filesize($_FILES['image']['tmp_name']);

//compare the size with the maxim size we defined and print error if bigger
if ($sizekb > 1150000)
{
echo '<b> Error! </b> - The file that you are attempting to upload is greater than the prescribed <b> 1MB </b> limit. Please try again.';
$errors=1;
}

//we will give an unique name, for example the time in unix time format
$image_name=time().'.'.$title.'.'.$extension;
//the new name will be containing the full path where will be stored (images folder)
$newname="images/".$image_name;
$copied = copy($_FILES['image']['tmp_name'], $newname);
if (!$copied) 
{
//echo '<b> Error! </b> Your file has not been loaded';
//$errors=1;
}
else
{
// the new thumbnail image will be placed in images/thumbs/ folder
$thumb_name='images/thumbs/'.$image_name;
// call the function that will create the thumbnail. The function will get as parameters 
//the image name, the thumbnail name and the width and height desired for the thumbnail
$thumb=make_thumb($newname,$thumb_name,WIDTH,HEIGHT);
} }}

//If no errors registred, print the success message and show the thumbnail image created
if(isset($_POST['Submit']) && !$errors) 
{
//echo '<br><b> Success! </b> - Your image has been uploaded</br>';
//echo '<img src="'.$thumb_name.'">';
}
require("mapmyfindsdbinfo.php");
// Gets data from form
$userid = $_POST["userid"];
$locationid = $_POST["locationid"];
$findosgb36lat = $_POST["findosgb36lat"];
$findosgb36lon = $_POST["findosgb36lon"];
$dateoftrip = $_POST["dateoftrip"];
$findcategory = $_POST["findcategory"];
$findname = $_POST["findname"];
$finddescription = $_POST["finddescription"];
$detectorid= $_POST["detectorname"];
$searchheadid = $_POST["searchheadname"];
if( empty($_POST["detectorsettings"]) ) {     
$detectorsettings = 'No details provided.'; } else {     
$detectorsettings = $_POST["detectorsettings"]; } 
if( empty($_POST["pasref"]) ) {     
$pasref = 'No PAS Ref. number provided.'; } else {     
$pasref = $_POST["pasref"]; } 
if( empty($_POST["additionalcomments"]) ) {     
$additionalcomments = 'No additional comments made.'; } else {     
$additionalcomments = $_POST["additionalcomments"]; } 
$makepublic = $_POST["makepublic"];

// Opens a connection to a MySQL server
$conn = mysql_connect ("hostname", $username, $password);
if (!$conn) {
  die('Not connected : ' . mysql_error());
}

// Set the active MySQL database
$db_selected = mysql_select_db($database, $conn);
if (!$db_selected) {
  die ('Can\'t use db : ' . mysql_error());
}

$sql = "INSERT INTO finds (userid, locationid, findosgb36lat, findosgb36lon, dateoftrip, findcategory, findname, finddescription, detectorid, searchheadid, detectorsettings, pasref, additionalcomments, makepublic) VALUES ('$userid', '$locationid', '$findosgb36lat', '$findosgb36lon', '$dateoftrip', '$findcategory', '$findname', '$finddescription', '$detectorid', '$searchheadid', '$detectorsettings', '$pasref', '$additionalcomments', '$makepublic')";
$result = mysql_query($sql, $conn);

$findid = mysql_insert_id($conn);

$sql = "INSERT INTO testimages (title, imagename, findid) VALUES ('$title', '$image_name', '$findid')";
$result = mysql_query($sql, $conn);

if (!$result) {
  die('Invalid query: ' . mysql_error());
}

?>

HTML 表单

<form name="savemyfindstolocation" method="post" enctype="multipart/form-data" action="savemyfindstolocation.php">
    <p align="left">Do You Wish To Add Find Images<label></label>
        <label></label>
    </p>
    <div align="left">
        <table id="addfiletable" border="1" style="table-layout:auto">
            <tr>
                <td>&nbsp;</td>
                <td><div align="center">Title</div></td>
                <td><div align="center">File Location </div></td>
            </tr>
            <tr>
                <td width="20"><input name="select" type="radio" id="select" title=""/></td>
                <td width="144"><input name="title" type="text" id="title"/></td>
                <td width="314"><input name="image" type="file" id="image" onchange="addRow();" size="40"/></td>
            </tr>
        </table>
        <div align="justify">
            <input type="submit" name="deleterow" value="Delete Row" />
        </div>
    </div>
    <input name="submit" type="submit" value="Submit" />        
</form>

一切都运行良好，但我现在想扩展允许用户一次上传多个文件的功能。我已经做了相当多的研究来了解如何上传多个文件，但我对 PHP 相当陌生，并且有点不确定哪种是实现这一目标的最佳方法。

我只是想知道是否有人可以看看我整理的内容，并提供一些关于如何更改此设置以在提交表单时上传多个文件的指导。

非常感谢

Answer 1

PHP

foreach($_FILES['image']['name'] as $i => $name)
{
    // now $name holds the original file name
    $tmp_name = $_FILES['image']['tmp_name'][$i];
    $error = $_FILES['image']['error'][$i];
    $size = $_FILES['image']['size'][$i];
    $type = $_FILES['image']['type'][$i];

    if($error === UPLOAD_ERR_OK)
    {
        $extension = getExtension($name);
        if( ! in_array(strtolower($extension, array('jpg', 'jpeg', 'png') )
        {
            // Error, invalid extension detected
        }
        else if ($size > $maxAllowedFileSize /* needs to be defined elsewhere */)
        {
            // Error, file too large
        }
        else
        {
            // No errors
            $newFileName = 'foo'; // You'll probably want something unique for each file.
            if(move_uploaded_file($tmp_file, $newFileName))
            {
                // Uploaded file successfully moved to new location
                $thumbName = 'thumb_image_name';
                $thumb = make_thumb($newFileName, $thumbName, WIDTH, HEIGHT);
            }
        }
    }
}

HTML

<form method="post" enctype="multipart/form-data">
    <input name="image[]" type="file" class="image-upload" />
    <input name="image[]" type="file" class="image-upload" />
    <input name="image[]" type="file" class="image-upload" />
    <input name="image[]" type="file" class="image-upload" />
    <input name="image[]" type="file" class="image-upload" />

    <!-- You need to add more, including a submit button -->
</form>

注意输入元素的名称。末尾的 [] 导致 PHP 创建一个数组并将项目添加到该数组中。