var xhr = new XMLHttpRequest();     xhr.onreadystatechange = function () {         if (xhr.readyState == 4 && xhr.status == 200) {            console.log(xhr.responseText);         }     };    xhr.open('post', gDatagridUrl, true);    xhr.setRequestHeader("Authorization", sessionStorage.getItem("token"));    xhr.setRequestHeader("Content-Type", "application/json");    xhr.setRequestHeader("Accept", "application/json");    // xhr.onload = function () {    //     if (this.status == 200) {    //         var res = this.response;    //         console.log(res)    //     }    // };    xhr.send();