var url="jk.php";var xhr = new XMLHttpRequest();xhr.onreadystatechange = function () { if (xhr.readyState == 4 (xhr.status = 200 xhr.status 400)) { var response = xhr.responseText; console.log("server response:"+response); }};xhr.open("GET"
          var url="jk.php";
var xhr = new XMLHttpRequest();
xhr.onreadystatechange = function () {
    if (xhr.readyState == 4 && (xhr.status >= 200 && xhr.status < 400)) {
        var response = xhr.responseText;
        console.log("server response:"+response);
    }
};
xhr.open("GET", url, true);
xhr.send(); 
 其实就是原生的js方法。
要想办法引入jq
