使用AJAX请求在PHP中保存base64编码的图像

Question

我将画布图像编码为base64，得到了以下内容：

data:image/jpeg;base64,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

这似乎是一个有效的Base64图片（使用在线解码器进行了解码）。

我用jquery ajax将其与其他（表单）变量一起发送，方法如下：

$.ajax({
    type: "POST",
    url: "index.php?action=saveNewPost",
    data: {text: text, img: encodeURIComponent(base64img)},
    contentType: "application/x-www-form-urlencoded;charset=UTF-8",
    success: function(){
        //...
    }
});

在服务器上，这个代码跑到以下这行：

saveImage(utf8_decode($_POST['img']));

调用以下内容：

function saveImage($base64img){
    define('UPLOAD_DIR', '../uploads/');
    $base64img = str_replace('data:image/jpeg;base64,', '', $base64img);
    $data = base64_decode($base64img);
    $file = UPLOAD_DIR . uniqid() . '.jpg';
    file_put_contents($file, $data);
}

然而，文件没有被保存。可能出了什么问题呢？

- Raphael Jeger

---

你有在那个文件夹中写入文件的权限吗？ - Barif

@Barif 我在该目录上执行了 chmod 777 命令，但仍然没有成功。 - Raphael Jeger

你确定你的图片能够正确地传递到你的 PHP 吗？ - Adil Shaikh

@MohammadAdil 我将"@base64img"（请参见上面的代码）写入了我的日志，并在网上对其进行了解码，这很顺利... - Raphael Jeger

Answer 1

让我们尝试在同一文件夹中创建名为test.php的文件，其中包含一个函数和一个调用，检查浏览器或/var/log/httpd/error_log中的错误输出。

<?php

function saveImage($base64img){
    define('UPLOAD_DIR', '../uploads/');
    $base64img = str_replace('data:image/jpeg;base64,', '', $base64img);
    $data = base64_decode($base64img);
    $file = UPLOAD_DIR . '123123123.jpg';
    file_put_contents($file, $data);
}

saveImage('data:image/jpeg;base64,/9j/4AAQSkZJRgABAQAAAQABAAD/2wBDAAICAgICAQICAgICAgIDAwYEAwMDAwcFBQQGCAcICAgHCAgJCg0LCQkMCggICw8LDA0ODg4OCQsQEQ8OEQ0ODg7/2wBDAQICAgMDAwYEBAYOCQgJDg4ODg4ODg4ODg4ODg4ODg4ODg4ODg4ODg4ODg4ODg4ODg4ODg4ODg4ODg4ODg4ODg7/wAARCAAKAAoDASIAAhEBAxEB/8QAHwAAAQUBAQEBAQEAAAAAAAAAAAECAwQFBgcICQoL/8QAtRAAAgEDAwIEAwUFBAQAAAF9AQIDAAQRBRIhMUEGE1FhByJxFDKBkaEII0KxwRVS0fAkM2JyggkKFhcYGRolJicoKSo0NTY3ODk6Q0RFRkdISUpTVFVWV1hZWmNkZWZnaGlqc3R1dnd4eXqDhIWGh4iJipKTlJWWl5iZmqKjpKWmp6ipqrKztLW2t7i5usLDxMXGx8jJytLT1NXW19jZ2uHi4+Tl5ufo6erx8vP09fb3+Pn6/8QAHwEAAwEBAQEBAQEBAQAAAAAAAAECAwQFBgcICQoL/8QAtREAAgECBAQDBAcFBAQAAQJ3AAECAxEEBSExBhJBUQdhcRMiMoEIFEKRobHBCSMzUvAVYnLRChYkNOEl8RcYGRomJygpKjU2Nzg5OkNERUZHSElKU1RVVldYWVpjZGVmZ2hpanN0dXZ3eHl6goOEhYaHiImKkpOUlZaXmJmaoqOkpaanqKmqsrO0tba3uLm6wsPExcbHyMnK0tPU1dbX2Nna4uPk5ebn6Onq8vP09fb3+Pn6/9oADAMBAAIRAxEAPwD5a/Z7/Zw8EfF/9mT4h6Z4u0GTwt8WNP1iSya7vZp0uNKYJBsItyANjt5o2uGkDBsHhMfDsOn2zWcTQ39tJCUBR5HVGYY4JUEgH2BIHrXunw71vWdI/aa+POraTq+p6Xqr+H/Edy15aXTxTNMt4m2QupDbxubDZyMn1r4yRE8pflXoO1fleQYDEzzHGxnXbjeEop6qPNFtpXb00Wm3zP1vNM2pUMLh5RpK75k3fV8rVm7LzP/Z');

这意味着问题部分在于AJAX => PHP脚本。现在，我们尝试比较从ajax接收到的内容和原始字符串，只需将您的函数更改为以下内容，并查看test.txt：

function saveImage($base64img){
    define('UPLOAD_DIR', '../uploads/');

    $file = UPLOAD_DIR . 'test.txt';
    file_put_contents($file, 'ORIG:'.'data:image/jpeg;base64,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'."\n".'AJAX:'.$base64img);
}

- Barif

Answer 2

你需要编写encodeURIComponent（JS）并使用utf8_decode（PHP）。只需使用urldecode（PHP）即可正常工作！ :)

- Quellcode

Answer 3

它有效 - 似乎当使用PHP包含文件时

include('file.php');

相对路径是从父文件而不是被包含的文件开始计算 :(

这就是整个问题所在... 感谢大家。

- Raphael Jeger