新版的JavaScript API里提供了一个全新的可以实现ajax的API——fetch，这个api采用了全新的 Promise 架构，使用起来更方便，更灵活，详细用法请参考《你不需要jQuery(三)：新AJAX方法fetch() 》。
>>>>JSON
jQuery
$.getJSON('/my/url', function(data) {
});
谷歌浏览器，火狐浏览器，IE8+
var request = new XMLHttpRequest();
request.open('GET', '/my/url', true);
request.onreadystatechange = function() {
if (this.readyState === 4) {
if (this.status >= 200 && this.status < 400) {
// Success!
var data = JSON.parse(this.responseText);
} else {
// Error :(
}
}
};
request.send();
request = null;
谷歌浏览器，火狐浏览器，IE9+
var request = new XMLHttpRequest();
request.open('GET', '/my/url', true);
request.onload = function() {
if (request.status >= 200 && request.status < 400) {
// Success!
var data = JSON.parse(request.responseText);
} else {
// We reached our target server, but it returned an error
}
};
request.onerror = function() {
// There was a connection error of some sort
};
request.send();
谷歌浏览器，火狐浏览器，IE10+
var request = new XMLHttpRequest();
request.open('GET', '/my/url', true);
request.onload = function() {
if (this.status >= 200 && this.status < 400) {
// Success!
var data = JSON.parse(this.response);
} else {
// We reached our target server, but it returned an error
}
};
request.onerror = function() {
// There was a connection error of some sort
};
request.send();
>>>>Post
jQuery
$.ajax({
type: 'POST',
url: '/my/url',
data: data
});
谷歌浏览器，火狐浏览器，IE8+
var request = new XMLHttpRequest();
request.open('POST', '/my/url', true);
request.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded; charset=UTF-8');
request.send(data);
>>>>Request
jQuery
$.ajax({
type: 'GET',
url: '/my/url',
success: function(resp) {
},
error: function() {
}
});
谷歌浏览器，火狐浏览器，IE8+
var request = new XMLHttpRequest();
request.open('GET', '/my/url', true);
request.onreadystatechange = function() {
if (this.readyState === 4) {
if (this.status >= 200 && this.status < 400) {
// Success!
var resp = this.responseText;
} else {
// Error :(
}
}
};
request.send();
request = null;
谷歌浏览器，火狐浏览器，IE9+
var request = new XMLHttpRequest();
request.open('GET', '/my/url', true);
request.onload = function() {
if (request.status >= 200 && request.status < 400) {
// Success!
var resp = request.responseText;
} else {
// We reached our target server, but it returned an error
}
};
request.onerror = function() {
// There was a connection error of some sort
};
request.send();
谷歌浏览器，火狐浏览器，IE10+
var request = new XMLHttpRequest();
request.open('GET', '/my/url', true);
request.onload = function() {
if (this.status >= 200 && this.status < 400) {
// Success!
var resp = this.response;
} else {
// We reached our target server, but it returned an error
}
};
request.onerror = function() {
// There was a connection error of some sort
};
request.send();