Question

我尝试在PHP中创建上传脚本。我收到此错误消息：

Notice: Undefined index: file in path\upload\index.php on line 3

这是我的表格（非常基本）：

<form action="upload" method="post" enctype="multipart/form-data">
   <input type="file" name="file" id="fileUpload">
   <input type="submit" value="Upload Image" name="submitt">
</form>

这是我的（不工作）上传脚本：

<?php
    $name       = $_FILES['file']['name'];
    $temp_name  = $_FILES['file']['tmp_name'];

    if(isset($name)){
        if(!empty($name)){
            $location = '../data/';
            if(move_uploaded_file($temp_name, $location.$name)){
                echo 'File uploaded successfully';
            }
        }
    }  else {
        echo 'You should select a file to upload !!';
    }
?>

这是我的php.ini配置：

; Whether to allow HTTP file uploads.
; http://php.net/file-uploads
file_uploads=On

; Maximum allowed size for uploaded files.
; http://php.net/upload-max-filesize
upload_max_filesize=40M

; Maximum number of files that can be uploaded via a single request
max_file_uploads=20

; Maximum size of POST data that PHP will accept.
; Its value may be 0 to disable the limit. It is ignored if POST data reading
; is disabled through enable_post_data_reading.
; http://php.net/post-max-size
post_max_size=50M

那我做错了什么。我查看了之前提出的所有问题，但未找到答案。

编辑1：

签出this并更改我的代码后问题仍然存在。

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

        if (isset($_FILES['file']) && isset($_FILES['file']['name']) && isset($_FILES['file']['tmp_name'])) {

            $name       = $_FILES['file']['name'];
            $temp_name  = $_FILES['file']['tmp_name'];

            if(!empty($name)){
                $location = '../data/';
                if(move_uploaded_file($temp_name, $location.$name)){
                    echo 'File uploaded successfully';
                }
            }  else {
                echo 'You should select a file to upload !!';
            }

        }
    }
?>

编辑2：

我发现了问题：用upload替换操作upload/index.php解决了问题。我在我的本地机器上使用XAMPP来测试我的代码。由于XAMPP本身的Apache配置不正确，这是一个错误。

Answer 1

在“上传”逻辑中，您需要确保在声明值之前已提交表单。否则，它试图用一个尚不存在的值设置变量;

<?php
    //ensures the form was submitted before declaring variable values
    if (isset($_POST['submitt']) {

        $name       = $_FILES['file']['name'];
        $temp_name  = $_FILES['file']['tmp_name'];

        if(isset($name)){
            if(!empty($name)){
                $location = '../data/';
                if(move_uploaded_file($temp_name, $location.$name)){
                    echo 'File uploaded successfully';
                }
            }
        }  else {
            echo 'You should select a file to upload !!';
        }
    }
?>

其次，更改您的表单代码，以便“操作”是自己的（在这种情况下，我们将action=""留空）：

<form action="" method="post" enctype="multipart/form-data">
   <input type="file" name="file" id="fileUpload">
   <input type="submit" value="Upload Image" name="submitt">
</form>

Answer 2

当用户提交表单并且没有选择文件来上传您的全局变量（数组）时，$_FILES将没有项目file，因此您有此错误，并且您必须检查是否密钥可用，如下：

if (isset($_FILES['file']) && isset($_FILES['file']['name']) && isset($_FILES['file']['tmp_name'])) {
    // Now you have strict and robust code!
    $name       = $_FILES['file']['name'];
    $temp_name  = $_FILES['file']['tmp_name'];
    // Rest of your code ...
}

PHP：$ _FILES []中的未定义索引

2 个答案: