Learn React with TypeScript 3

Request HTTP headers

Very often, we need to include HTTP headers in the request. We can specify these in the options object in a headers property:

fetch("https://jsonplaceholder.typicode.com/posts", { method: "POST", headers: {  "Content-Type": "application/json",  Authorization: "bearer some-bearer-token"  },  body: JSON.stringify({    title: "Interesting post",    body: "This is an interesting post about ...",    userId: 1  })})  .then(response => {    console.log(response.status);     return response.json();  })  .then(data => console.log(data));

Request headers can be used in this way for any HTTP method and not just an HTTP POST. For example, we can use this for a GET request as follows:

fetch("https://jsonplaceholder.typicode.com/posts/1", {  headers: { "Content-Type": ...