微信小程序下载、打开及预览PDF文件的方法

//下载PDF文件 
function downLoadPDF(){
     wx.showModal({
        title: '提示',
        content: '确认要打开此PDF政策文件吗？',
        showCancel: true,
        cancelText: '取消',
        confirmText: '确定',
        success: (result) => {
          if (result.confirm) {
            wx.downloadFile({
              url: 'https://********/file/preview/XG-2019-01.pdf',    //示例的url地址
              success: function (resinfo) {
      
                  let path = resinfo.tempFilePath;
                  console.log(path, resinfo)
                  wx.openDocument({
                      filePath: path,
                      fileType: 'pdf',
                      success: function (rest) {
                          console.log('打开文件成功')
                          console.log(rest);
                      },
                      fail: function (error) {
                          wx.showToast({
                              icon: 'none',
                              title: '打开文件失败'
                          });
                      },
                  })
              },
              fail: function (err) {
                  console.log('fail')
                  console.log(err)
                  wx.showToast({
                    icon: 'none',
                    title: '下载文件失败'
                });
              }
          })     
          }
        },
        fail: () => {},
        complete: () => {}
      })
}