post、get、axios、fetch请求方法

// post请求：

function post() {
  var xmlhttp;
  if (window.XMLHttpRequest) {
    // ?IE7+, Firefox, Chrome, Opera, Safari 浏览器执行代码
    xmlhttp = new XMLHttpRequest();
  }
  else{
    // IE6, IE5 浏览器执行代码
    xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
  }
  var str = '';
  var postData = {
    "mobile": 15626192509,
    "password": 12313
  };
  postData = (function(value){
    for(var key in value){
      str + = key + "=" + value[key] + "&";
    };
    return str;
  }(postData));

  xmlhttp.open("POST","地址",true);//连接到服务器
  xmlhttp.setRequestHeader("Content-type","application/x-www-form-urlencoded");//设置头部信息
  xmlhttp.send(postData);//发送数据
  xmlhttp.onreadystatechange = function() {//响应服务器时所做的准备
    if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {//响应成功
     var data = JSON.parse(xmlhttp.responseText);//解析数据
    console.log(data);
    }
  }
}

post();

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// get请求：

function get(){
  var xmlhttp;
  if (window.XMLHttpRequest){
    // ?IE7+, Firefox, Chrome, Opera, Safari 浏览器执行代码
    xmlhttp = new XMLHttpRequest();
  }
  else{
    // IE6, IE5 浏览器执行代码
    xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
  }
  xmlhttp.onreadystatechange = function() {
    if (xmlhttp.readyState == 4 && xmlhttp.status == 200){
    var data = JSON.parse(xmlhttp.responseText);
  }
    }
  xmlhttp.open("GET","地址",true);
  xmlhttp.send();
}

get()

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原生jsonp 方法：

var sc = document.createElement("script");
sc.type = "text/javascript";
document.body.appendChild(sc);
sc.src = "http://localhost/ajax2/jsonp.php?cb=myCallBack";

function myCallBack(data){
  console.log(data);
}

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// axios请求：

axios({
  method: 'post',
  url: '/user/12345',
  data: {
    firstName: 'Fred',
    lastName: 'Flintstone'
  }
})
.then(function (response) {
  console.log(response);
})
.catch(function (error) {
  console.log(error);
});

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// fetch请求：

try {
  let response = await fetch(url);
  let data = response.json();
  console.log(data);
} catch(e) {
  console.log("Oops, error", e);
}