有同样的错误，因为我忘记发送一个正确的头

header("Content-type: text/css; charset: UTF-8");
print 'body { text-align: justify; font-size: 2em; }';

使用的反应

我在我的react profile应用程序中遇到了这个错误。我的应用程序表现得有点像它试图引用一个不存在的url。我相信这与webpack的行为有关。

如果你在公用文件夹中链接文件，你必须记住在资源之前使用%PUBLIC_URL%，就像这样:

<link type="text/css" rel="stylesheet" href="%PUBLIC_URL%/bootstrap.min.css" />

有同样的错误，因为我忘记发送一个正确的头

header("Content-type: text/css; charset: UTF-8");
print 'body { text-align: justify; font-size: 2em; }';

答案可以在上面给出。我也遇到过同样的问题，但无法解决。确保添加外部js文件为

<script src="main.js"></script>

根据其他的回答，这条消息似乎有很多原因，我想我只是分享我的个人解决方案，以防将来有人有我的确切问题。

Our site loads the CSS files from an AWS Cloudfront distribution, which uses an S3 bucket as the origin. This particular S3 bucket was kept synced to a Linux server running Jenkins. The sync command via s3cmd sets the Content-Type for the S3 object automatically based on what the OS says (presumably based on the file extension). For some reason, in our server, all the types were being set correctly except .css files, which it gave the type text/plain. In S3, when you check the metadata in the properties of a file, you can set the type to whatever you want. Setting it to text/css allowed our site to correctly interpret the files as CSS and load correctly.

我在为一个用npm安装的React布局模块加载CSS时遇到了这个问题。你必须导入两个.css文件来让这个模块运行，所以我最初导入它们是这样的:

@import "../../../../node_modules/react-grid-layout/css/styles.css";

但发现文件扩展名必须被删除，所以这是有效的:

@import "../../../../node_modules/react-grid-layout/css/styles";