如何使用JavaScript进行AJAX调用,而不使用jQuery?
当前回答
使用下面的代码片段,你可以很容易地完成类似的事情,就像这样:
ajax.get('/test.php', {foo: 'bar'}, function() {});
以下是片段:
var ajax = {};
ajax.x = function () {
if (typeof XMLHttpRequest !== 'undefined') {
return new XMLHttpRequest();
}
var versions = [
"MSXML2.XmlHttp.6.0",
"MSXML2.XmlHttp.5.0",
"MSXML2.XmlHttp.4.0",
"MSXML2.XmlHttp.3.0",
"MSXML2.XmlHttp.2.0",
"Microsoft.XmlHttp"
];
var xhr;
for (var i = 0; i < versions.length; i++) {
try {
xhr = new ActiveXObject(versions[i]);
break;
} catch (e) {
}
}
return xhr;
};
ajax.send = function (url, callback, method, data, async) {
if (async === undefined) {
async = true;
}
var x = ajax.x();
x.open(method, url, async);
x.onreadystatechange = function () {
if (x.readyState == 4) {
callback(x.responseText)
}
};
if (method == 'POST') {
x.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
}
x.send(data)
};
ajax.get = function (url, data, callback, async) {
var query = [];
for (var key in data) {
query.push(encodeURIComponent(key) + '=' + encodeURIComponent(data[key]));
}
ajax.send(url + (query.length ? '?' + query.join('&') : ''), callback, 'GET', null, async)
};
ajax.post = function (url, data, callback, async) {
var query = [];
for (var key in data) {
query.push(encodeURIComponent(key) + '=' + encodeURIComponent(data[key]));
}
ajax.send(url, callback, 'POST', query.join('&'), async)
};
其他回答
使用“vanilla”(普通)JavaScript:
function loadXMLDoc() {
var xmlhttp = new XMLHttpRequest();
xmlhttp.onreadystatechange = function() {
if (xmlhttp.readyState == XMLHttpRequest.DONE) { // XMLHttpRequest.DONE == 4
if (xmlhttp.status == 200) {
document.getElementById("myDiv").innerHTML = xmlhttp.responseText;
}
else if (xmlhttp.status == 400) {
alert('There was an error 400');
}
else {
alert('something else other than 200 was returned');
}
}
};
xmlhttp.open("GET", "ajax_info.txt", true);
xmlhttp.send();
}
jQuery:
$.ajax({
url: "test.html",
context: document.body,
success: function() {
$(this).addClass("done");
}
});
这只是一个简单的4步过程,
我希望这对你们有帮助
步骤1。存储对XMLHttpRequest对象的引用
var xmlHttp = createXmlHttpRequestObject();
步骤2。检索XMLHttpRequest对象
function createXmlHttpRequestObject() {
// will store the reference to the XMLHttpRequest object
var xmlHttp;
// if running Internet Explorer
if (window.ActiveXObject) {
try {
xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
} catch (e) {
xmlHttp = false;
}
}
// if running Mozilla or other browsers
else {
try {
xmlHttp = new XMLHttpRequest();
} catch (e) {
xmlHttp = false;
}
}
// return the created object or display an error message
if (!xmlHttp)
alert("Error creating the XMLHttpRequest object.");
else
return xmlHttp;
}
步骤3。使用XMLHttpRequest对象进行异步HTTP请求
function process() {
// proceed only if the xmlHttp object isn't busy
if (xmlHttp.readyState == 4 || xmlHttp.readyState == 0) {
// retrieve the name typed by the user on the form
item = encodeURIComponent(document.getElementById("input_item").value);
// execute the your_file.php page from the server
xmlHttp.open("GET", "your_file.php?item=" + item, true);
// define the method to handle server responses
xmlHttp.onreadystatechange = handleServerResponse;
// make the server request
xmlHttp.send(null);
}
}
步骤4。当从服务器接收消息时自动执行
function handleServerResponse() {
// move forward only if the transaction has completed
if (xmlHttp.readyState == 4) {
// status of 200 indicates the transaction completed successfully
if (xmlHttp.status == 200) {
// extract the XML retrieved from the server
xmlResponse = xmlHttp.responseText;
document.getElementById("put_response").innerHTML = xmlResponse;
// restart sequence
}
// a HTTP status different than 200 signals an error
else {
alert("There was a problem accessing the server: " + xmlHttp.statusText);
}
}
}
var load_process = false;
function ajaxCall(param, response) {
if (load_process == true) {
return;
}
else
{
if (param.async == undefined) {
param.async = true;
}
if (param.async == false) {
load_process = true;
}
var xhr;
xhr = new XMLHttpRequest();
if (param.type != "GET") {
xhr.open(param.type, param.url, true);
if (param.processData != undefined && param.processData == false && param.contentType != undefined && param.contentType == false) {
}
else if (param.contentType != undefined || param.contentType == true) {
xhr.setRequestHeader('Content-Type', param.contentType);
}
else {
xhr.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
}
}
else {
xhr.open(param.type, param.url + "?" + obj_param(param.data));
}
xhr.onprogress = function (loadTime) {
if (param.progress != undefined) {
param.progress({ loaded: loadTime.loaded }, "success");
}
}
xhr.ontimeout = function () {
this.abort();
param.success("timeout", "timeout");
load_process = false;
};
xhr.onerror = function () {
param.error(xhr.responseText, "error");
load_process = false;
};
xhr.onload = function () {
if (xhr.status === 200) {
if (param.dataType != undefined && param.dataType == "json") {
param.success(JSON.parse(xhr.responseText), "success");
}
else {
param.success(JSON.stringify(xhr.responseText), "success");
}
}
else if (xhr.status !== 200) {
param.error(xhr.responseText, "error");
}
load_process = false;
};
if (param.data != null || param.data != undefined) {
if (param.processData != undefined && param.processData == false && param.contentType != undefined && param.contentType == false) {
xhr.send(param.data);
}
else {
xhr.send(obj_param(param.data));
}
}
else {
xhr.send();
}
if (param.timeout != undefined) {
xhr.timeout = param.timeout;
}
else
{
xhr.timeout = 20000;
}
this.abort = function (response) {
if (XMLHttpRequest != null) {
xhr.abort();
load_process = false;
if (response != undefined) {
response({ status: "success" });
}
}
}
}
}
function obj_param(obj) {
var parts = [];
for (var key in obj) {
if (obj.hasOwnProperty(key)) {
parts.push(encodeURIComponent(key) + '=' + encodeURIComponent(obj[key]));
}
}
return parts.join('&');
}
我的ajax调用
var my_ajax_call=ajaxCall({
url: url,
type: method,
data: {data:value},
dataType: 'json',
async:false,//synchronous request. Default value is true
timeout:10000,//default timeout 20000
progress:function(loadTime,status)
{
console.log(loadTime);
},
success: function (result, status) {
console.log(result);
},
error :function(result,status)
{
console.log(result);
}
});
对于中止先前的请求
my_ajax_call.abort(function(result){
console.log(result);
});
如果您不想包含JQuery,我建议您尝试一些轻量级AJAX库。
我最喜欢的是reqwest。它只有3.4kb,构建得非常好:https://github.com/ded/Reqwest
下面是一个带有reqwest的GET请求示例:
reqwest({
url: url,
method: 'GET',
type: 'json',
success: onSuccess
});
现在,如果您想要更轻量级的东西,我将尝试仅需0.4kb的microAjax: https://code.google.com/p/microajax/
这是所有的代码:
function microAjax(B,A){this.bindFunction=function(E,D){return function(){return E.apply(D,[D])}};this.stateChange=function(D){if(this.request.readyState==4){this.callbackFunction(this.request.responseText)}};this.getRequest=function(){if(window.ActiveXObject){return new ActiveXObject("Microsoft.XMLHTTP")}else{if(window.XMLHttpRequest){return new XMLHttpRequest()}}return false};this.postBody=(arguments[2]||"");this.callbackFunction=A;this.url=B;this.request=this.getRequest();if(this.request){var C=this.request;C.onreadystatechange=this.bindFunction(this.stateChange,this);if(this.postBody!==""){C.open("POST",B,true);C.setRequestHeader("X-Requested-With","XMLHttpRequest");C.setRequestHeader("Content-type","application/x-www-form-urlencoded");C.setRequestHeader("Connection","close")}else{C.open("GET",B,true)}C.send(this.postBody)}};
下面是一个示例调用:
microAjax(url, onSuccess);
这是一个没有JQuery的JSFiffle
http://jsfiddle.net/rimian/jurwre07/
function loadXMLDoc() {
var xmlhttp = new XMLHttpRequest();
var url = 'http://echo.jsontest.com/key/value/one/two';
xmlhttp.onreadystatechange = function () {
if (xmlhttp.readyState == XMLHttpRequest.DONE) {
if (xmlhttp.status == 200) {
document.getElementById("myDiv").innerHTML = xmlhttp.responseText;
} else if (xmlhttp.status == 400) {
console.log('There was an error 400');
} else {
console.log('something else other than 200 was returned');
}
}
};
xmlhttp.open("GET", url, true);
xmlhttp.send();
};
loadXMLDoc();