Make sure to place app.UseCors before any other middleware that might process requests.
Step 4: Handle CORS Preflight Requests (Optional)
For some requests, especially those with custom headers or HTTP methods other than the basic ones (GET, POST, PUT, DELETE), the browser may send a preflight request (OPTIONS) to check if the server allows the actual request. You can handle these preflight requests by adding a separate CORS policy with the .AllowAnyMethod() and .AllowAnyHeader() methods, or by using the .AllowAnyOrigin() method, but be cautious about using this option as it allows any origin to access your API:
Then, in your Configure method, add app.UseCors to apply this policy:
Step 5: Test CORS Configuration
With CORS configured, your ASP.NET Core application should now allow cross-origin requests from the specified origins. Test your CORS configuration by making requests from your client application hosted on the allowed domains to your ASP.NET Core API.
Remember that CORS policies can vary depending on your specific requirements and security considerations. Always configure CORS to be as restrictive as necessary for your application's security needs.