小程序-下载文件的方式

正常下载的时候，出现下载的时候空白，基本是格式出现问题，或者是文件名出现问题。文件不能是中文

  downloadFile(originURL, fileName, success)  {let filePath = `${wx.env.USER_DATA_PATH}/${fileName}`;
      wx.downloadFile({url: originURL,filePath: filePath,header: {'sessionId': getApp().globalData.openId,},success: (res) => {wx.hideLoading();if(res.statusCode == 200) {if (success) {success(res);}}},fail: (res) => {wx.showToast({title: '下载失败',icon: 'none',});},});
  },onSaveDocument(val, callback) {wx.getSystemInfo({success: function (res) {if (res.platform === 'windows') {wx.saveFileToDisk({filePath: val,})} else callback()}});},opFile: function (e) {const fileName = e.currentTarget.dataset.name;const eng = e.currentTarget.dataset.eng;const type = e.currentTarget.dataset.type;const geturl = 'https://www.baidu.com/doc/' + eng;const originURL = decodeURI(geturl);const that = this;const fileValue = {data: ''};this.downloadFile(originURL, fileName,(res) => {fileValue.data = res.filePath;that.onSaveDocument(res.filePath, () => {wx.openDocument({filePath: res.filePath,showMenu: true,});});},)},