StorageFolder.CreateFileQueryWithOptions(QueryOptions) Method

Reference

Definition

Namespace:: Windows.Storage

Important

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Edit

Gets a query result object that contains the files in the current folder and, optionally, in the subfolders of the current folder. The results are based on the specified QueryOptions.

public:
 virtual StorageFileQueryResult ^ CreateFileQueryWithOptions(QueryOptions ^ queryOptions) = CreateFileQueryWithOptions;

StorageFileQueryResult CreateFileQueryWithOptions(QueryOptions const& queryOptions);

public StorageFileQueryResult CreateFileQueryWithOptions(QueryOptions queryOptions);

function createFileQueryWithOptions(queryOptions)

Public Function CreateFileQueryWithOptions (queryOptions As QueryOptions) As StorageFileQueryResult

Parameters

queryOptions: QueryOptions

The criteria that are applied to the query.

Returns

StorageFileQueryResult

A query result object that contains the files in the current folder and, optionally, in the subfolders of the current folder, filtered and sorted based on the specified QueryOptions. Call the GetFilesAsync method of the query result to get the flat list of files, sorted as specified by queryOptions. This method returns a list of type IReadOnlyList<StorageFile>. Each file is represented by an item of type StorageFile.

Implements

CreateFileQueryWithOptions(QueryOptions)

Exceptions

ArgumentException

You specified a value other than DefaultQuery from the CommonFileQuery enumeration for a folder that's not a library folder. Check the value of query.

Examples

The following example shows how to get the JPG files in the user's Pictures folder and its subfolders, sorted by date, by calling the CreateFileQueryWithOptions(QueryOptions) method. This query is a deep query because the folder is a library folder and a value other than DefaultQuery from the CommonFileQuery enumeration is specified.

Before you run the following example, enable the Pictures Library capability in the app manifest file.

using Windows.Storage;
using Windows.Storage.Search;
using System.Threading.Tasks;
using System.Diagnostics; // For writing results to Output window.

// Get the user's Pictures folder.
// Enable the corresponding capability in the app manifest file.
StorageFolder picturesFolder = KnownFolders.PicturesLibrary;

// Set options for file type and sort order.
List<string> fileTypeFilter = new List<string>();
fileTypeFilter.Add(".jpg");
QueryOptions queryOptions = new QueryOptions(CommonFileQuery.OrderByDate, fileTypeFilter);

// Get the JPG files in the user's Pictures folder
// and its subfolders and sort them by date.
StorageFileQueryResult results = picturesFolder.CreateFileQueryWithOptions(queryOptions);

// Iterate over the results and print the list of files
// to the Visual Studio Output window.
IReadOnlyList<StorageFile> sortedFiles = await results.GetFilesAsync();
foreach (StorageFile item in sortedFiles)
{
    Debug.WriteLine(item.Name + ", " + item.DateCreated);
}

IAsyncAction MainPage::ExampleCoroutineAsync()
{
    // Get the users's Pictures folder.
    // Enable the Pictures Library capability in the app manifest file.
    Windows::Storage::StorageFolder picturesFolder{ Windows::Storage::KnownFolders::PicturesLibrary() };

    // Set options for file type and sort order.
    Windows::Storage::Search::QueryOptions queryOptions{ Windows::Storage::Search::CommonFileQuery::OrderByDate, { L".png" } };

    // Get the png files in the user's Pictures folder and its subfolders, sorted by date.
    Windows::Storage::Search::StorageFileQueryResult results{ picturesFolder.CreateFileQueryWithOptions(queryOptions) };

    Windows::Foundation::Collections::IVectorView<Windows::Storage::StorageFile> filesInFolder{
        co_await results.GetFilesAsync() };

    // Iterate over the results, and print the list of files to the Visual Studio output window.
    for (StorageFile const& fileInFolder : filesInFolder)
    {
        std::wstring output{ fileInFolder.Name() };
        ::OutputDebugString(output.c_str());
    }
}

//Get the users's pictures folder
//Enable the corresponding capability in the app manifest file
StorageFolder^ picturesFolder = KnownFolders::PicturesLibrary;

//Set options for file type and sort order
Platform::Collections::Vector<String^>^ fileTypeFilter = ref new Platform::Collections::Vector<String^>();
fileTypeFilter->Append(".jpg");
QueryOptions^ queryOptions = ref new QueryOptions(Windows::Storage::Search::CommonFileQuery::OrderByDate, fileTypeFilter);

//Get the JPG files in the user's pictures folder 
//and its subfolders and sort them by date
StorageFileQueryResult^ results = picturesFolder->CreateFileQueryWithOptions(queryOptions);

create_task(results->GetFilesAsync()).then([=](IVectorView<StorageFile^>^ filesInFolder) 
{
    //Iterate over the results and print the list of files
    // to the visual studio output window
    for (auto it = filesInFolder->First(); it->HasCurrent; it->MoveNext())
    {
             StorageFile^ file = it->Current;
             String^ output = file->Name + "\n";
             OutputDebugString(output->Begin());
    }
});

Remarks

In the following cases, this query is a shallow query that returns only files in the current folder:

Default behavior of this method if none of the following options are specified. Or:
Specify DefaultQuery as the value of CommonFileQuery when you instantiate the QueryOptions object. Or:
Specify Shallow as the value of the FolderDepth property of the QueryOptions object.

In the following cases, this query is a deep query that returns files from the current folder and from its subfolders:

For a library folder, specify a value other than DefaultQuery as the value of CommonFileQuery when you instantiate the QueryOptions object. Or:
For any folder, specify Deep as the value of the FolderDepth property of the QueryOptions.

Tip

Some of the values from the CommonFileQuery enumeration can only be used with a library folder (such as the Pictures library) or the Homegroup folder. Despite the wording of the ArgumentException described above, you can use the OrderByName and OrderBySearchRank options (in addition to the DefaultQuery option) with a folder that's not a library folder.

For a list of methods that identifies shallow queries and deep queries, see the Remarks in the topic GetFilesAsync.

To check whether the QueryOptions you want to specify are available for the current folder, call the folder's AreQueryOptionsSupported method. To check whether a specific CommonFileQuery is available, call the folder's IsCommonFileQuerySupported method.

You can also get a list of files in the current folder asynchronously by calling one of the GetFilesAsync methods.

To get a query result object that contains the files in the current folder without configuring a QueryOptions object, call one of the CreateFileQuery methods.

To get items that are files or folders, call the CreateItemQueryWithOptions method.

Note

For Windows Server 2012, you must install indexer components to use some QueryOptions because indexer components are not installed by default.

Applies to

Delen via