原生ajax下载，pdf，execl等

deliveryCode传的你要下载的code

mimeograph:function(deliveryCode,that){
                //原生ajax
                var xhr = new XMLHttpRequest();
                //post方式请求后台的路径
                // xhr.open('get', window.BAOSIGHT.API.DELIVERY.PRINT_INFO+'?deliveryCode='+deliveryCode,true);
                xhr.open('post',window.BAOSIGHT.API.DELIVERY.PRINT_OUTSIDE_THE_PACKAGE,true);
                //导出的Pdf是二进制数据类型，所以设置为arraybuffer
                xhr.responseType = 'arraybuffer';
                //请求头（key,value），请求头可以设置多个key-value对
                xhr.setRequestHeader('Content-Type', 'application/json;charset=utf-8');
                xhr.setRequestHeader('Authorization', that.global.getLocalStorage("Authorization") );
                // var formData = new FormData();
                //     formData.append('deliveryCode',that.defaults.deliveryCode);
                //  console.log(formData)
                //返回成功，导出的Pdf文件
                xhr.onload = function () {
                        
                 if (this.status == 200) {
                  // new Blob 默认转换 blod,转arraybuffer需要增加 type
                  var blob = new Blob([this.response],{type: "arraybuffer"});
                //   var fileName = 'lichun.pdf'
                  if (window.navigator && window.navigator.msSaveBlob) {
                   //兼容ie 下载 msSaveBlob 仅支持保存  msSaveOrOpenBlob 支持保存or代开
                   window.navigator.msSaveBlob(blob, fileName);
                  }else{
                   var a = document.createElement('a');
                   var url = window.URL.createObjectURL(blob);
                   a.href = url;
                   //设置文件名称
                   a.download = '包装信息外.pdf';
                   a.click();
                  }
                 }
                };
                //请求的参数，json格式，后台要用json格式接收
                xhr.send(JSON.stringify(deliveryCode));
            },