Answers

1. The problem is that the fetch function expects the body to be in string format. The corrected call is as follows:

   fetch('http://localhost:17525/api/person', {
     method: 'post',
     headers: {
       'Content-Type': 'application/json',
     },
     body: JSON.stringify({
       firstName: 'Fred'
       surname: 'Smith'
     })
   })

2. The problem is that the response body cannot be accessed directly in the response like this. Instead, the response's json asynchronous method should be used:

   const res = await fetch('http://localhost:17525/api/person/1');
   const body = await res.json();
   console.log('firstName', body.firstName);

3. The problem is that the catch method is for network errors and not HTTP request errors. HTTP request errors can be dealt with in the...