public async void Share2Timeline()
{
var file = await Windows.Storage.StorageFile.GetFileFromApplicationUriAsync(new Uri("ms-appx:///Assets/StoreLogo.png"));
using (var stream = await file.OpenReadAsync())
{
var pic = new byte[stream.Size];
await stream.AsStream().ReadAsync(pic, 0, pic.Length);
WeChatRequest req = new WeChatRequest("123456789");
req.WebPageShare2TimelineRequest(ShareUrl, Title, pic);
}
}