import (
	"context"
	xhr "github.com/rocketlaunchr/gopherjs-xhr"
	"github.com/gopherjs/gopherjs/js"
	"github.com/rocketlaunchr/react/forks/encoding/json"
)
req := xhr.NewRequest("POST", reqURL)
req.ResponseType = xhr.Text // Returns response as string
req.SetRequestHeader("Content-Type", xhr.ApplicationForm)
postBody := NewParams(js.M{"setting": 4})
err := req.Send(context.Background(), postBody.String())
if err != nil {
	// Could not connect to internet???
	// Unfortunately XMLHttpRequest does not provide nuanced reasons.
	return
}
if !req.IsStatus2xx() {
	// Something went wrong
	return
}
// Unmarshal json response here using encoding/json. Otherwise set req.ResponseType = "json".
err = json.Unmarshal(req.ResponseBytes(), &sb)