自定义ReqUtil.js工具_requestutil.js-优快云博客

本文链接：https://blog.youkuaiyun.com/however_zx/article/details/122476974

以上代码为前端同事遗留代码分享,我一般都是用 ajax,第一次看见这么写的。
系统后台定义的返回报文

前端请求后台接口后,后台返回的固定格式:
{
    "code":"200",
    "msg":"返回消息",
    "data":"返回数据"
}

前端自定义js 请求封装util工具


const utils = {
  dopost: function (path, pramas, callback) {
    var xmlhttp = XMLHttpRequest
      ? new XMLHttpRequest()
      : new ActiveXObject("Microsoft.XMLHTTP");
    var onXmlhttpStateChange = function () {
      if (xmlhttp.readyState === 4) utils.onGetResponse(xmlhttp, callback);
    };
    xmlhttp.open("POST", path, true);
    xmlhttp.setRequestHeader("content-type", "application/json");
    xmlhttp.send(JSON.stringify(pramas));
    xmlhttp.onreadystatechange = onXmlhttpStateChange;
  },
  doget: function (path, callback) {
    var xmlhttp = XMLHttpRequest
      ? new XMLHttpRequest()
      : new ActiveXObject("Microsoft.XMLHTTP");
    var onXmlhttpStateChange = function () {
      if (xmlhttp.readyState === 4) utils.onGetResponse(xmlhttp, callback);
    };
    xmlhttp.open("GET", path, true);
    xmlhttp.send();
    xmlhttp.onreadystatechange = onXmlhttpStateChange;
  },
  checkJsonResponse: function (res, callback) {
    if (res.code === "500" || res.code === 500) {
      utils.message("错误：" + res.msg || "服務器異常！");
    } else {
      callback(res);
    }
  },
  
  onHttpSuccess: function (response, callback) {
    var res = {};
    var isJson = 1;
    var handler = [utils.checkJsonResponse];
    try {
      res = JSON.parse(response);
    } catch (e) {
      isJson = 0;
    }
    handler[isJson](res, callback);
  },
  onGetResponse: function (xmlhttp, callback) {
    if (xmlhttp.status === 200) {
      utils.onHttpSuccess(xmlhttp.response, callback);
    } else {
      utils.message("错误：" + xmlhttp.response);
    }
  },
  message: function (str) {
    window.alert(str);
  },
};