1

我想从浏览器窗口将图像上传到我的服务器。但是，上传字段对每个人都是可见的，所以我需要设置一些限制。我只找到了 w3schools 文件上传（从 w3fools.com 开始，我不相信它）。我希望限制是：

最大尺寸 2,5M

图像类型 jpg、jpeg、png、gif

所以这是 w3schools 提供的代码，但它实际上不会将文件保存在任何地方？我已经对其进行了一些修改以满足我的需要。

<?php
$allowedExts = array("jpg", "jpeg", "gif", "png");
$extension = end(explode(".", $_FILES["file"]["name"]));
if ((($_FILES["file"]["type"] == "image/gif")
|| ($_FILES["file"]["type"] == "image/jpg")
|| ($_FILES["file"]["type"] == "image/jpeg"))
|| ($_FILES["file"]["type"] == "image/png"))
&& ($_FILES["file"]["size"] < 2500000)
&& in_array($extension, $allowedExts))
  {
  if ($_FILES["file"]["error"] > 0)
    {
    echo "Error: " . $_FILES["file"]["error"] . "<br />";
    }
  else
    {
    echo "Upload: " . $_FILES["file"]["name"] . "<br />";
    echo "Type: " . $_FILES["file"]["type"] . "<br />";
    echo "Size: " . ($_FILES["file"]["size"] / 1024) . " Kb<br />";
    echo "Stored in: " . $_FILES["file"]["tmp_name"];
    }
  }
else
  {
  echo "Invalid file";
  }
?>

由于我不希望我的网站被黑客入侵，我想要一个安全的解决方案，对此有什么帮助吗？

编辑

代码甚至什么都不做。那么我该怎么做呢？

4

4 回答 4

3

您需要使用 php move_upload_file 函数，并且我已经对您的 if 语句进行了更改，这是工作和测试的示例：

<?php

if (isset($_REQUEST["submit"])) {

    $allowedExts = array("jpg", "jpeg", "gif", "png");
    $extension = end(explode(".", $_FILES["file"]["name"]));

    if ($_FILES["file"]["type"] == "image/gif" || $_FILES["file"]["type"] == "image/jpg" || $_FILES["file"]["type"] == "image/jpeg" || $_FILES["file"]["type"] == "image/png" && $_FILES["file"]["size"] < 2500000 && in_array($extension, $allowedExts)) {

      if ($_FILES["file"]["error"] > 0) {

        echo "Error: " . $_FILES["file"]["error"] . "<br />";

      }
      else {

        $fname = $_FILES["file"]["name"];
        move_uploaded_file($_FILES["file"]["tmp_name"], $fname);

        echo "Upload: " . $_FILES["file"]["name"] . "<br />";
        echo "Type: " . $_FILES["file"]["type"] . "<br />";
        echo "Size: " . ($_FILES["file"]["size"] / 1024) . " Kb<br />";
        echo "Stored in: " . $fname;

      }

    }
    else {

      echo "Invalid file type";

    }

}
?>
<form action="" method="post" enctype="multipart/form-data">
<input type="file" name="file" />
<input type="submit" name="submit" value="submit" />
</form>

您还可以按照以下建议使用 getimagesize 函数：

$size = getimagesize("http://www.simplestudio.rs/060620121945.jpg");

$file_format = $size['mime'];

$file_format 将表示为例如“image/jpeg”，因此您可以轻松检查图像类型，如下所示：

foreach($allowedExts as $allowed) {

$chk_types = strpos($file_format, $allowed);

if($chk_types > -1) {
$type_is_good = true;
break;
}

}
于 2012-09-27T08:39:37.033 回答
1

使用：move_uploaded_file，请参阅，手册

还有一件事情，

该$_FILES["file"]["type"]变量不好使用，因为它可以通过浏览器设置进行更改。

请改用 getimagesize，请参阅，手册

于 2012-09-27T08:30:50.870 回答
0
  1. $ratio2) { $thumb_w=$new_w; $thumb_h=$old_y/$ratio1; } 其他 { $thumb_h=$new_h; $thumb_w=$old_x/$ratio2; } 
        $dst_img=ImageCreateTrueColor($thumb_w,$thumb_h);

    imagecopyresampled($dst_img,$src_img,0,0,0,0,$thumb_w,$thumb_h,$old_x,$old_y);

            if(!strcmp("png",$ext))             imagepng($dst_img,$filename);       else            imagejpeg($dst_img,$filename); 
        imagegif($dst_img,$filename);
            imagedestroy($dst_img);         imagedestroy($src_img);   }  }  if(!function_exists('getExtension'))    {       function
    getExtension($str) { $i = strrpos($str,"."); if (!$i) { return ""; } $l = strlen($str) - $i; $ext = substr($str,$i+1,$l); 返回 $ext; } } 
    $image=$_FILES["$imagename"]['name'];   if($image)      {  
    $filename = stripslashes($_FILES["$imagename"]['name']); 
    $extension = getExtension($filename);       $extension =
    strtolower($extension); if (($extension != "jpg") && ($extension != "jpeg") && ($extension != "png") && ($extension != "gif") && ($extension != "bmp" )) { 
            $obj->set_flash("Unknown extension...!");           header("Location: $filename ");             exit;       }       else        {

        $size=getimagesize($_FILES["$imagename"]['tmp_name']);
        $sizekb=filesize($_FILES["$imagename"]['tmp_name']);

        if ($sizekb > MAX_SIZE*1024)
        {
            $obj->set_flash("You have exceeded the size limit...!");
            header("Location: $filename");
            exit;
        }

    $select_max = $obj->sql_query("select max($fieldname) as MaxID from  ".$tablename."");
                    if($action=="Add")          {
            $Max = $select_max[0]['MaxID'];
            $image_name = $Max + 1;
            $new_name = $image_name.".".$extension;//the new name will be containing the full path where will be stored (images folder)
            $$imagename = $new_name;//New Name of Image same as Image Field Name
            $thumbfilename = $new_name;
            $newname="$uploadpath/large/".$new_name;

            $copied = copy($_FILES["$imagename"]['tmp_name'], $newname);
            //we verify if the image has been uploaded, and print error instead
            if (!$copied) 
            { 
                $obj->set_flash("Copy unsuccessfull...!");
                header("Location: $filename");
                exit;
            }
            else
            {
                $thumb_name="$uploadpath/thumb/".$thumbfilename;
                $thumb=make_thumb($newname,$thumb_name,$WIDTH,$HEIGHT);
            }           }           if($action=="Update")           {

            $new_name=$ID.".".$extension;
            $$imagename = $new_name;//New Name of Image same as Image Field Name
            $newname = "$uploadpath/large/".$new_name;
            $thumbfilename = $new_name;
            $copied = copy($_FILES["$imagename"]['tmp_name'], $newname);

            if (!$copied) 
            {
                $obj->set_flash("Copy unsuccessfull...!");
                header("Location: $filename");
                exit;
            }
            else
            {
                $thumb_name="$uploadpath/thumb/".$thumbfilename;
                $thumb=make_thumb($newname,$thumb_name,$WIDTH,$HEIGHT);
            }           }       }   }       if($action=="Delete")   {       $SelectImage = $obj->sql_query("select $imagename from  $tablename where $fieldname
    = ".$$ 字段名。" "); $ThisImage = $SelectImage[0]["$imagename"]; unlink("$uploadpath/thumb/".$ThisImage); unlink("$uploadpath/large/".$ThisImage); } ?>
    1. 项目清单
于 2013-07-21T10:55:02.703 回答
0 
<?php

          $file_name   = $_FILES['file']['name'];
          $file_size   = $_FILES['file']['size'];
          $file_tmp    = $_FILES['file']['tmp_name'];
          $file_type   = $_FILES['file']['type'];

          /* variable array for store errors */
          $errors   = [];                   


          /* Check if file already exists in location file save */
          $file_dir  = "uploads";
          /** if folder not exists, then create it **/
          if (!file_exists($file_dir)) {
            mkdir($file_dir, 0777, true);
          }

          $file_target = $file_dir . $file_name;
          if (file_exists($file_target)) {
            //$errors[] = "Sorry, <strong>{$file_name}</strong> already exists.";
          }


             /* Check file size */
          if ($file_size > 2500000) {
            $errors[] = "Sorry, <strong>{$file_name}</strong> is too large. It size is {$file_size} > 2500000 bytes";
          }


          /* Check current file formats with file secure */
          $file_secure  = array('jpg', 'jpeg', 'png', 'gif');                   
          $file_current = strtolower(pathinfo($file_name, PATHINFO_EXTENSION)); /* (end(explode('.', $file_name) */

          if (in_array($file_current, $file_secure) === false) {
            $errors[] = "Sorry, <strong>{$file_current}</strong> extension not allowed";            
          }


          /* Check if Errors exist, then not upload. Or if Errors NOT exist, then try upload */
          if (!empty($errors)) {                            

            /* display error */                 
            foreach ($errors as $keyError => $valueError) {
              echo "$keyError = $valueError <br />";
            }

            echo "<br />";
            echo "<strong>{$file_name}</strong> could not uploaded. <hr />";                            

          } else {

            if (move_uploaded_file($file_tmp, $file_target)) {

              echo "Upload: "    . $file_name . "<br />";
              echo "Type: "      . $file_type . "<br />";
              echo "Size: "      . ($file_size / 1024) . " Kb<br />";
              echo "Stored in: " . $file_tmp;

            } else {

              echo "Invalid file";

            }

          }

?>
于 2017-11-20T02:34:20.967 回答