PHP文件上传大小和类型不起作用答案

【问题标题】：PHP file upload size & type not workingPHP文件上传大小和类型不起作用
【发布时间】：2016-06-25 19:46:37
【问题描述】：

实际上，我已经开发了一个 CMS，可以通过...发布到我的网站。对于发布图像，我想设置 500KB 的限制，并且只允许使用 GIF、JPEG、JPG 和 PNG 格式。此代码执行成功并且警报也出现了。但是当上传包含允许的格式和大小的图像时，它会再次显示警报消息..我在这里使用exit();function 是正确的吗？ HTML 是：

<div class="form-container">
   <form method="post" action="publish_post.php" enctype="multipart/form-data">
     <input class="inputs" type="text" name="p_title" placeholder="What's the post title"/>
     <input class="inputs" type="text" name="p_author" placeholder="Who's the post author"/>
     <select class="input" name="p_category" size="1" />
        <option value="null">Select post category</option>
        <option value="softwares">Softwares</option>
        <option value="tips & tricks">Tips & tricks</option>
        <option value="wallpapers">Wallpapers</option>
        <option value="walpapers_more">Walpapers_more</option>
     </select>
     <textarea name="p_content" placeholder="What's the post content"></textarea>
     <textarea name="p_misc" placeholder="Enter an html code"></textarea>
     <textarea name="p_video" placeholder="Enter an embed code"></textarea>
     </br>
     <div class="upload">
     <input type="file" name="p_image" title="Pick an image for post"/>
     </div></br>
      <span style="margin-left: 5px; color: gray; font-family: sans-serif; font-size: .8em; ">max. size 5MB
      </span></br></br>
     <input type="submit" name="pub" value="Publish"/>
     <input type="button" name="cancel" value="Cancel" onclick="window.open('dashboard','_self');"/>
   </form>
 </div>

PHP 是：

<?php
if(isset($_POST['pub'])){

    $category = mysqli_real_escape_string($con,$_POST['p_category']);
    $author = mysqli_real_escape_string($con,$_POST['p_author']);
    $title = mysqli_real_escape_string($con,$_POST['p_title']);
    $content = mysqli_real_escape_string($con,$_POST['p_content']);
    $image_name = $_FILES['p_image']['name'];
    $image_type = $_FILES['p_image']['type'];
    $image_size = $_FILES['p_image']['size'];
    $image_tmp = $_FILES['p_image']['tmp_name'];
    $date = date("M,d,Y");
    $misc = $_POST['p_misc'];
    $video = $_POST['p_video'];

    if($image_type != "jpg" && $image_type != "png" && $image_type != "gif" && $image_type != "jpeg" && $image_size>500000)
    {
        echo "<script>alert('Image size is larger or invlaid format');</script>";
        exit();
    }

$query = "INSERT INTO `me`(`post_category`, `post_author`, `post_title`, `post_content`, `post_image`, `post_date`, `post_misc`, `post_video`) VALUES ('$category','$author','$title','$content','$image_name','$date','$misc','$video')";

    if(mysqli_query($con,$query))
    {
    move_uploaded_file($image_tmp,"images/$image_name");
    header("location:dashboard?done2=done2.png");
    }
  } 
?>

【问题讨论】：

标签： php mysqli

【解决方案1】：

//图片类型

$expensions= array("jpeg","jpg","png","gif");
if(in_array($image_type,$expensions)=== false){
    echo "<script>alert('Image size is larger or invlaid format');</script>";
    exit();
}

//图片大小

if($image_size  > 500000){
    echo "<script>alert('Image size is larger or invlaid format');</script>";
    exit();
}

希望对你有帮助

【讨论】：

【解决方案2】：

在 if 条件下试试这个：

unset($_POST);  
exit("<script>alert('Image size is larger or invlaid format');</script>");

并确保您的插入查询看起来像这样

$query = "INSERT INTO `me`(`post_category`, `post_author`, `post_title`, `post_content`, `post_image`, `post_date`, `post_misc`, `post_video`) VALUES ('".$category."','".$author."','".$title."','".$content."','".$image_name."','".$date."','".$misc."','".$video."')";

【讨论】：

【解决方案3】：

if(($image_type != "image/jpeg" && $image_type != "image/png" && $image_type != "image/gif") || $image_size > 500000)
{
    echo "<script>alert('Image size is larger or invalid format');</script>";

}
else
{
    echo "<script>alert('valid format');</script>";
}

【讨论】：

【解决方案4】：

条件不成立。试试这段代码。如果你有更多的条件，试试这个方法。

if(($image_type != "jpg") && ($image_type != "png") && ($image_type != "gif") && ($image_type != "jpeg") && ($image_size>500000))
{
   echo "<script>alert('Image size is larger or invlaid format');</script>";
   exit();
}

【讨论】：