This seems like a simple problem to solve, but I can't figure it out at all. I have followed the

Then I try to test this route:

I've tried testing it using the same method as the existing, working fetch call is made from the react app to the back end server:

    // The example used in the tutorial and it works OK:
    const response = await fetch('weatherforecast');
    const data = await response.json();
    this.setState({ forecasts: data, loading: false });
    // I have imitated this to send a fetch to the "api/test3" route, which doesn't work
    const response = await fetch('api/test3');
    const data = await response.json();
    this.setState({ forecasts: data, loading: false });

But I cant work out what is different for one to be failing and one to be working. I have updated the setupProxy.js file and added the new routes:

const { createProxyMiddleware } = require('http-proxy-middleware');

const context = [
    "/weatherforecast",
    "/test",
    "/api",
    "/api/test",
    "/api/test3",
    "/test2",
];

module.exports = function (app) {
    const appProxy = createProxyMiddleware(context, {
        target: 'https://localhost:7236',
        secure: false
    });

    app.use(appProxy);
};

I also tried adding these to my package.json:

  "private": true,
  "proxy": "https://localhost:7236",

I've also tried replacing all of the script in a new controller with the same script as in the working WeatherForecastController.cs from the tutorial. This gives the same error.

CodePudding user response：

The problem resolved itself (as if by magic) when I restarted Visual Studio. I'd tried that once or twice already, so perhaps one of the changes I made helped resolve the issue:

1. Add this to package.json

  "private": true,
  "proxy": "https://localhost:7236",

2. Ensure setupProxy.js is updated with the necessary endpoints, as above.

Other solutions that I didn't try, but may also have solved my problem:

3. Removing the service worker, as per this solution

I have to say I've lost a lot of time trying to debug Visual Studio & .NET issues only to find the issue resolved by restarting Visual Studio. It would be handy if there was a button/feature to reload VisualStudio; delete the cache; and do whatever else is necessary for my current code to compile. If anyone knows then please let me know.