XMLHttpRequest的封装和调用(加入JSONP功能)
封装:
function ajax(params) {
params = params || {};
params.data = params.data || {};
var json = params.jsonp ? jsonp(params) : json(params);
function json(params) {
params.type = (params.type || 'GET').toUpperCase();
params.data = formatParams(params.data);
var xhr = null;
if (window.XMLHttpRequest) {
xhr = new XMLHttpRequest();
} else {
xhr = new ActiveXObjcet('Microsoft.XMLHTTP');
};
xhr.onreadystatechange = function () {
if (xhr.readyState == 4) {
var status = xhr.status;
if (status >= 200 && status < 300) {
var response = '';
var type = xhr.getResponseHeader('Content-type');
if (type.indexOf('xml') !== -1 && xhr.responseXML) {
response = xhr.responseXML;
} else if (type === 'application/json') {
response = JSON.parse(xhr.responseText);
} else {
response = xhr.responseText;
};
params.success && params.success(response);
} else {
params.error && params.error(status);
}
}
};
if (params.type == 'GET') {
xhr.open(params.type, params.url + '?' + params.data, true);
xhr.send(null);
} else {
xhr.open(params.type, params.url, true);
xhr.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded; charset=UTF-8');
xhr.send(params.data);
}
}
function jsonp(params) {
var callbackName = params.jsonp;
var head = document.getElementsByTagName('head')[0];
params.data['callback'] = callbackName;
var data = formatParams(params.data);
var script = document.createElement('script');
head.appendChild(script);
window[callbackName] = function (json) {
head.removeChild(script);
clearTimeout(script.timer);
window[callbackName] = null;
params.success && params.success(json);
};
script.src = params.url + '?' + data;
if (params.time) {
script.timer = setTimeout(function () {
window[callbackName] = null;
head.removeChild(script);
params.error && params.error({
message: '超时'
});
}, time);
}
};
function formatParams(data) {
var arr = [];
for (var name in data) {
arr.push(encodeURIComponent(name) + '=' + encodeURIComponent(data[name]));
};
arr.push('v=' + random());
return arr.join('&');
}
function random() {
return Math.floor(Math.random() * 10000 + 500);
}
}
调用:get || post
ajax({
url: "url",
type: 'POST',
jsonp: 'jsonpCallbak',
data: {
key1:'value1',
key2:'value2'
},
success: function (res) {},
error: function (error) {}
});
Fetch api
- 目前只有新款浏览器支持
- 兼容Ie需要添加插件:https://github.com/github/fetch
fetch("http://localhost:3000/api/notes",{
method:"POST",
headers: {
'Content-Type': 'application/json',
'Accept': 'application/json'
},
body: JSON.stringify({
})
}).then((res) => {
console.log(res)
return res.json().then(
(json) => {
console.log(json)
}
)
}
}).catch((error)=>{
console.log(error)
})