What is this request header used for?

Question

原生ajaxde

request.setRequestHeader('content-type','application/x-www-form-urlencoded');

Answer 1

When the action is get, the browser uses the x-www-form-urlencoded encoding method to convert the form data into a string (name1=value1&name2=value2...), then appends the string to the end of the url, splits it with ?, and loads it. this new url.