Javascript拦截XMLHttpRequest请求,修改Response内容

 1.先执行下面的代码,实现全局拦截

let origin = XMLHttpRequest.prototype.open;

  XMLHttpRequest.prototype.open = function (...args) {
    //在这里插入open拦截代码
    this.__on_response=function(res){return res}
    return origin.apply(this, args);
  };
  var accessor = Object.getOwnPropertyDescriptor(
    XMLHttpRequest.prototype,
    "response"
  );

  Object.defineProperty(XMLHttpRequest.prototype, "response", {
    get: function () {
      let response = accessor.get.call(this);

      //在__on_response里修改你的response
      response=this.__on_response(res)

      return response;
    },
    set: function (str) {
      return accessor.set.call(this, str);
    },
    configurable: true,
  });
}

2.拦截示例代码

let req=new XMLHttpRequest()
req.__on_response=function(res){
    
    return res+"/modified"
}
req.open()
req.send(method, url, async);

console.log(req.response)