php - 将图像上传到服务器时重命名图像

Question

我正在尝试上传图片，但我希望如果图片已经存在，那么我需要重命名该文件。当我尝试在重命名文件后上传图像时，我的代码中出现了问题。我面临问题的代码部分是。重命名后，如果我回显文件的名称，它会被更改，但之后我无法将图像上传到服务器

if(file_exists($target_file))
    {
        $new_filename =  uniqid() . '.' . $fileData['imageFileType'];
        rename($target_file, $new_filename);
        if (move_uploaded_file($_FILES["fileToUpload"]["tmp_name"], $target_file)) 
            {
                $name=basename( $_FILES["fileToUpload"]["name"]);
                echo $name;
            } 
        else 
            {
                echo "Sorry, there was an error uploading your file.";
            }
    }
else    
    {
        if (move_uploaded_file($_FILES["fileToUpload"]["tmp_name"], $target_file)) 
            {
                $name=basename( $_FILES["fileToUpload"]["name"]);
                echo $name;
            } 
        else 
            {
                echo "Sorry, there was an error uploading your file.";
            }

    }

我上传图片的全部代码是

<?php
require 'connection.php';

$target_dir = "catpic/";
$target_file = $target_dir . basename($_FILES["fileToUpload"]["name"]);
$uploadOk = 1;
$imageFileType = pathinfo($target_file,PATHINFO_EXTENSION);
// Check if image file is a actual image or fake image
if(isset($_POST["submit"])) 
    {
        $check = getimagesize($_FILES["fileToUpload"]["tmp_name"]);
        if($check !== false) 
            {
                //echo "File is an image - " . $check["mime"] . ".";
                $uploadOk = 1;
            }
        else 
            {
                echo "File is not an image.";
                $uploadOk = 0;
            }
    }

// Check file size
if ($_FILES["fileToUpload"]["size"] > 500000) 
    {
        echo "Sorry, your file is too large.";
        $uploadOk = 0;
    }

// Allow certain file formats
if($imageFileType != "jpg" && $imageFileType != "png" && $imageFileType != "jpeg" && $imageFileType != "gif" ) 
    {
        echo "Sorry, only JPG, JPEG, PNG & GIF files are allowed.";
        $uploadOk = 0;
    }

// Check if $uploadOk is set to 0 by an error
if ($uploadOk == 0) 
    {
        echo "Sorry, your file was not uploaded.";
        // if everything is ok, try to upload file
    }
else 
    {
        if(file_exists($target_file))
            {
                $new_filename =  uniqid() . '.' . $fileData['imageFileType'];
                rename($target_file, $new_filename);
                if (move_uploaded_file($_FILES["fileToUpload"]["tmp_name"], $target_file)) 
                    {
                        $name=basename( $_FILES["fileToUpload"]["name"]);
                        echo $name;
                    } 
                else 
                    {
                        echo "Sorry, there was an error uploading your file.";
                    }
            }
        else    
            {
                if (move_uploaded_file($_FILES["fileToUpload"]["tmp_name"], $target_file)) 
                    {
                        $name=basename( $_FILES["fileToUpload"]["name"]);
                        echo $name;
                    } 
                else 
                    {
                        echo "Sorry, there was an error uploading your file.";
                    }

            }
    }
?>

Answer 1

您在 $new_filename 中缺少路径

比较两个声明

$target_file = $target_dir . basename($_FILES["fileToUpload"]["name"]);

$new_filename =  uniqid() . '.' . $fileData['imageFileType'];

我正在更新我的答案以符合您的建议尝试替换您的代码的这一部分

$new_filename =  uniqid() . '.' . $fileData['imageFileType'];
rename($target_file, $new_filename);

与

$new_filename = $target_dir . uniqid() . '.' . $imageFileType;
   if (move_uploaded_file($_FILES["fileToUpload"]["tmp_name"], $new_filename)){

只需添加 $target_dir 并删除不需要的 rename()

基本上，当文件在上传过程中存在时，您在之前的代码中所做的是您尝试使用 rename() 重命名旧文件，这可能不会成功，之后您尝试上传具有相同冲突名称的新文件