例外，在WinRT加載文件後

Question

我有一些問題。這裏是我的代碼：

private async void SetCollectionForGame() 
{ 
    maincollection = new Dictionary<string, string>(); 

    bool statebase = await CheckExistingBase(); 

    if (statebase) 
    { 
     //If file exists... 
     basefile = await folder.GetFileAsync(basefilename); 
    } 
    else 
    { 
     //If file does not exist... 
     SaveBaseFileAsync(filelink, folder, basefilename); 
     basefile = await folder.GetFileAsync(basefilename); 
    } 
    string content = String.Empty; 
    content = await FileIO.ReadTextAsync(basefile, Windows.Storage.Streams.UnicodeEncoding.Utf8); 
    //When the app first starts, I get an exception on the next line, 
    //because the variable "content" is null. 
    maincollection = JsonConvert.DeserializeObject<CollectionModel>(content).collection; 
} 

有沒有人知道如何解決這個問題？文件下載工作正常，下載後文件創建在一個文件夾中。

Answer 1

基於名稱，我懷疑SaveBaseFileAsync（）會執行一些異步操作。如果這是真的，你需要等待它的，即把它作爲

await SaveBaseFileAsync(filelink, folder, basefilename);