Resolving CORS Policy Blockage: 'No 'Access-Control-Allow-Origin' Header' Error
In web development, when attempting to make cross-origin requests, such as fetching data from a URL with a different origin than the requesting page, a common error message encountered is "Redirect has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource." This error arises due to the CORS (Cross-Origin Resource Sharing) security policy, which restricts unauthorized requests for protecting user privacy.
To rectify this issue, there are several approaches you can consider:
Firstly, you can reach out to the server administrator responsible for the URL you're trying to fetch from. The administrator can configure the server to include the necessary 'Access-Control-Allow-Origin' header in the response, allowing your request from the specific origin. However, this may not always be feasible, especially during local development.
An alternative solution is to utilize a Chrome plugin that modifies the origin of the request. Two such plugins that serve this purpose are:
- Moesif Origin & CORS Changer
- Allow CORS: Access-Control-Allow-Origin
By installing one of these plugins, you can temporarily allow cross-origin requests from your local server to the target URL. This approach enables you to work around the CORS restriction, but it's crucial to remember that it's primarily a temporary solution. When deploying your application to a production environment, the server should be configured correctly to handle CORS requests.
The above is the detailed content of How to Fix the 'No 'Access-Control-Allow-Origin' Header' Error?. For more information, please follow other related articles on the PHP Chinese website!

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