StorageFolder.TryGetItemAsync(String) Method

Reference

Definition

Namespace:: Windows.Storage

Important

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Edit

Tries to get the file or folder with the specified name from the current folder. Returns null instead of raising a FileNotFoundException if the specified file or folder is not found.

public:
 virtual IAsyncOperation<IStorageItem ^> ^ TryGetItemAsync(Platform::String ^ name) = TryGetItemAsync;

/// [Windows.Foundation.Metadata.RemoteAsync]
IAsyncOperation<IStorageItem> TryGetItemAsync(winrt::hstring const& name);

[Windows.Foundation.Metadata.RemoteAsync]
public IAsyncOperation<IStorageItem> TryGetItemAsync(string name);

function tryGetItemAsync(name)

Public Function TryGetItemAsync (name As String) As IAsyncOperation(Of IStorageItem)

Parameters

name: String
Platform::String

winrt::hstring

The name (or path relative to the current folder) of the file or folder to get.

Returns

IAsyncOperation<IStorageItem>

When this method completes successfully, it returns an IStorageItem that represents the specified file or folder. If the specified file or folder is not found, this method returns null instead of raising an exception.

To work with the returned item, call the IsOfType method of the IStorageItem interface to determine whether the item is a file or a folder. Then cast the item to a StorageFolder or StorageFile.

Implements

M:Windows.Storage.IStorageFolder2.TryGetItemAsync(System.String) M:Windows.Storage.IStorageFolder2.TryGetItemAsync(Platform::String) M:Windows.Storage.IStorageFolder2.TryGetItemAsync(winrt::hstring)

Attributes: RemoteAsyncAttribute

Examples

The following example shows how to try to get a single file or folder from the current folder, or to check whether the file or folder exists, by calling the TryGetItemAsync method.

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

// Get the path to the app's Assets folder.
string root = Windows.ApplicationModel.Package.Current.InstalledLocation.Path;
string path = root + @"\Assets";

// Get the app's Assets folder.
StorageFolder assetsFolder = await StorageFolder.GetFolderFromPathAsync(path);

// Check whether an image with the specified scale exists.
string imageName = "Logo.scale-140.png";
if (await assetsFolder.TryGetItemAsync(imageName) != null)
    Debug.WriteLine(imageName + " exists.");
else  // Return value of TryGetItemAsync is null.
    Debug.WriteLine(imageName + " does not exist.");

IAsyncAction MainPage::ExampleCoroutineAsync()
{
    std::wstring imageName{ L"Wide310x150Logo.scale-200.png" };

    // Get the path to the app's Assets folder.
    std::wstring path{ Windows::ApplicationModel::Package::Current().InstalledLocation().Path() + L"\\Assets" };

    // Get the folder object that corresponds to this absolute path in the file system.
    Windows::Storage::StorageFolder assets{ co_await Windows::Storage::StorageFolder::GetFolderFromPathAsync(path) };
    IStorageItem image{ co_await assets.TryGetItemAsync(imageName) };

    std::wstring output;
    if (image)
    {
        output = L"File: " + image.Name() + L" found \n";
    }
    else
    {
        output = L"File not found\n";
    }
    ::OutputDebugString(output.c_str());
}

String^ imageName = "Logo.scale-140.png";
// Get the app'ss Assets folder
String^ path = Windows::ApplicationModel::Package::Current->InstalledLocation->Path + "\\Assets";

create_task(StorageFolder::GetFolderFromPathAsync(path)).then([=](StorageFolder^ assets) -> task < IStorageItem^ > 
{
 return create_task(assets->TryGetItemAsync(imageName));
}).then([=](IStorageItem^ image) {
 String^ output = "";
 if (image == nullptr)
 {
  output = "File not found\n";
 }
 else
 {
  //output = "File: " + image->Name + " found \n";
 }
 OutputDebugString(output->Begin());
});

Remarks

Call the TryGetItemAsync method to try to get a file or folder by name, or to check whether a file or folder exists, without the need to handle a FileNotFoundException. If the file or folder can't be found, TryGetItemAsync returns null instead of raising an exception.

Call the IsOfType method of the IStorageItem interface to determine whether the returned item is a file or a folder.

Applies to

Delen via