UWP：如何從 Documents 文件夾的子文件夾中獲取所有文本文件名的列表

Question

學習為 Windows 10 開發。我試圖訪問文檔文件夾內的子文件夾並列出子文件夾中存在的所有文本文件名。 請幫忙。

Answer 1

如果要訪問 Documents 文件夾，可以使用FolderPicker或KnownFolders.DocumentsLibrary方法。

關於FolderPicker，你需要通過與picker交互來訪問文件夾，但是你可以直接選擇你想要的文件夾。 關於KnownFolders.DocumentsLibrary方法，您需要添加額外的wideFileSystemAccess 功能並允許您的應用在設置中訪問文件系統。

//FolderPicker
var folderPicker = new Windows.Storage.Pickers.FolderPicker();
folderPicker.SuggestedStartLocation = Windows.Storage.Pickers.PickerLocationId.DocumentsLibrary;
folderPicker.FileTypeFilter.Add("*");
Windows.Storage.StorageFolder subFolder = await folderPicker.PickSingleFolderAsync();

//KnownFolders.DocumentsLibrary
//StorageFolder Myfolder = KnownFolders.DocumentsLibrary;
//StorageFolder subFolder = await Myfolder.GetFolderAsync("YouSubFolder");
​
List<string> fileTypeFilter = new List<string>();
fileTypeFilter.Add(".txt");
QueryOptions queryOptions = new QueryOptions(Windows.Storage.Search.CommonFileQuery.OrderByName, fileTypeFilter);
StorageFileQueryResult queryResult = subFolder.CreateFileQueryWithOptions(queryOptions);
var files = await queryResult.GetFilesAsync();
foreach (var file in files)
{
    string name = file.Name;
}