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StorageFile.GetThumbnailAsync Method

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Definition

Namespace:
Windows.Storage

Overloads

GetThumbnailAsync(ThumbnailMode, UInt32, ThumbnailOptions)

Retrieves an adjusted thumbnail image for the file, determined by the purpose of the thumbnail, the requested size, and the specified options.
GetThumbnailAsync(ThumbnailMode)

Retrieves an adjusted thumbnail image for the file, determined by the purpose of the thumbnail.
GetThumbnailAsync(ThumbnailMode, UInt32)

Retrieves an adjusted thumbnail image for the file, determined by the purpose of the thumbnail and the requested size.

GetThumbnailAsync(ThumbnailMode, UInt32, ThumbnailOptions)

Edit

Retrieves an adjusted thumbnail image for the file, determined by the purpose of the thumbnail, the requested size, and the specified options.

public:
 virtual IAsyncOperation<StorageItemThumbnail ^> ^ GetThumbnailAsync(ThumbnailMode mode, unsigned int requestedSize, ThumbnailOptions options) = GetThumbnailAsync;
/// [Windows.Foundation.Metadata.Overload("GetThumbnailAsync")]
/// [Windows.Foundation.Metadata.RemoteAsync]
IAsyncOperation<StorageItemThumbnail> GetThumbnailAsync(ThumbnailMode const& mode, uint32_t const& requestedSize, ThumbnailOptions const& options);
[Windows.Foundation.Metadata.Overload("GetThumbnailAsync")]
[Windows.Foundation.Metadata.RemoteAsync]
public IAsyncOperation<StorageItemThumbnail> GetThumbnailAsync(ThumbnailMode mode, uint requestedSize, ThumbnailOptions options);
function getThumbnailAsync(mode, requestedSize, options)
Public Function GetThumbnailAsync (mode As ThumbnailMode, requestedSize As UInteger, options As ThumbnailOptions) As IAsyncOperation(Of StorageItemThumbnail)

Parameters

mode
ThumbnailMode

The enum value that describes the purpose of the thumbnail and determines how the thumbnail image is adjusted.

For guidance about choosing the best thumbnail mode, see Guidelines and checklist for thumbnails.

requestedSize
UInt32

unsigned int

uint32_t

The requested size, in pixels, of the longest edge of the thumbnail. Windows uses the requestedSize as a guide and tries to scale the thumbnail image without reducing the quality of the image.

If Windows can't find a thumbnail image that it can scale to meet the requested size, a larger thumbnail might be returned. If no larger thumbnail is available, a thumbnail image that is smaller than the requested size might be returned.

options
ThumbnailOptions

The enum value that describes the desired behavior to use to retrieve the thumbnail image. The specified behavior might affect the size and/or quality of the image and how quickly the thumbnail image is retrieved.

Returns

IAsyncOperation<StorageItemThumbnail>

When this method completes successfully, it returns a StorageItemThumbnail that represents the thumbnail image or null if there is no thumbnail image associated with the file.

Implements

M:Windows.Storage.IStorageItemProperties.GetThumbnailAsync(Windows.Storage.FileProperties.ThumbnailMode,System.UInt32,Windows.Storage.FileProperties.ThumbnailOptions) M:Windows.Storage.IStorageItemProperties.GetThumbnailAsync(Windows.Storage.FileProperties.ThumbnailMode,unsigned int,Windows.Storage.FileProperties.ThumbnailOptions) M:Windows.Storage.IStorageItemProperties.GetThumbnailAsync(Windows.Storage.FileProperties.ThumbnailMode,uint32_t,Windows.Storage.FileProperties.ThumbnailOptions)
Attributes
OverloadAttribute RemoteAsyncAttribute

Examples

This example shows you how to capture the thumbnail of a file using the [storageFile.getThumbnailAsync(mode, requestedSize, options) method.

storageFile.getThumbnailAsync(
    Windows.Storage.FileProperties.ThumbnailMode.musicView,
    100,
    Windows.Storage.FileProperties.ThumbnailOptions.useCurrentScale).then(
        function (storageItemThumbnail) {
            // Add code to process thumbnail
        }
    );

You must have a StorageFile object (storageFile in the example) that represents your file in order to use one of the StorageFile.GetThumbnailAsync methods.

Remarks

While GetThumbnailAsync adheres to the max size supported by the thumbnail disk cache, GetScaledImageAsThumbnailAsync can extract thumbnails that are larger than what the thumbnail disk cache supports. GetScaledImageAsThumbnailAsync provides optimal quality but can affect performance by not using the disk cache if the thumbnail size is too large.

See also

Applies to

GetThumbnailAsync(ThumbnailMode)

Edit

Retrieves an adjusted thumbnail image for the file, determined by the purpose of the thumbnail.

public:
 virtual IAsyncOperation<StorageItemThumbnail ^> ^ GetThumbnailAsync(ThumbnailMode mode) = GetThumbnailAsync;
/// [Windows.Foundation.Metadata.Overload("GetThumbnailAsyncOverloadDefaultSizeDefaultOptions")]
/// [Windows.Foundation.Metadata.RemoteAsync]
IAsyncOperation<StorageItemThumbnail> GetThumbnailAsync(ThumbnailMode const& mode);
[Windows.Foundation.Metadata.Overload("GetThumbnailAsyncOverloadDefaultSizeDefaultOptions")]
[Windows.Foundation.Metadata.RemoteAsync]
public IAsyncOperation<StorageItemThumbnail> GetThumbnailAsync(ThumbnailMode mode);
function getThumbnailAsync(mode)
Public Function GetThumbnailAsync (mode As ThumbnailMode) As IAsyncOperation(Of StorageItemThumbnail)

Parameters

mode
ThumbnailMode

The enum value that describes the purpose of the thumbnail and determines how the thumbnail image is adjusted.

For guidance about choosing the best thumbnail mode, see Guidelines and checklist for thumbnails.

Returns

IAsyncOperation<StorageItemThumbnail>

When this method completes successfully, it returns a StorageItemThumbnail that represents the thumbnail image or null if there is no thumbnail image associated with the file.

Implements

GetThumbnailAsync(ThumbnailMode)
Attributes
OverloadAttribute RemoteAsyncAttribute

Remarks

While GetThumbnailAsync adheres to the max size supported by the thumbnail disk cache, GetScaledImageAsThumbnailAsync can extract thumbnails that are larger than what the thumbnail disk cache supports. GetScaledImageAsThumbnailAsync provides optimal quality but can affect performance by not using the disk cache if the thumbnail size is too large.

See also

Applies to

GetThumbnailAsync(ThumbnailMode, UInt32)

Edit

Retrieves an adjusted thumbnail image for the file, determined by the purpose of the thumbnail and the requested size.

public:
 virtual IAsyncOperation<StorageItemThumbnail ^> ^ GetThumbnailAsync(ThumbnailMode mode, unsigned int requestedSize) = GetThumbnailAsync;
/// [Windows.Foundation.Metadata.Overload("GetThumbnailAsyncOverloadDefaultOptions")]
/// [Windows.Foundation.Metadata.RemoteAsync]
IAsyncOperation<StorageItemThumbnail> GetThumbnailAsync(ThumbnailMode const& mode, uint32_t const& requestedSize);
[Windows.Foundation.Metadata.Overload("GetThumbnailAsyncOverloadDefaultOptions")]
[Windows.Foundation.Metadata.RemoteAsync]
public IAsyncOperation<StorageItemThumbnail> GetThumbnailAsync(ThumbnailMode mode, uint requestedSize);
function getThumbnailAsync(mode, requestedSize)
Public Function GetThumbnailAsync (mode As ThumbnailMode, requestedSize As UInteger) As IAsyncOperation(Of StorageItemThumbnail)

Parameters

mode
ThumbnailMode

The enum value that describes the purpose of the thumbnail and determines how the thumbnail image is adjusted.

For guidance about choosing the best thumbnail mode, see Guidelines and checklist for thumbnails.

requestedSize
UInt32

unsigned int

uint32_t

The requested size, in pixels, of the longest edge of the thumbnail. Windows uses the requestedSize as a guide and tries to scale the thumbnail image without reducing the quality of the image.

If Windows can't find a thumbnail image that it can scale to meet the requested size, a larger thumbnail might be returned. If no larger thumbnail is available, a thumbnail image that is smaller than the requested size might be returned.

Returns

IAsyncOperation<StorageItemThumbnail>

When this method completes successfully, it returns a StorageItemThumbnail that represents the thumbnail image or null if there is no thumbnail image associated with the file.

Implements

M:Windows.Storage.IStorageItemProperties.GetThumbnailAsync(Windows.Storage.FileProperties.ThumbnailMode,System.UInt32) M:Windows.Storage.IStorageItemProperties.GetThumbnailAsync(Windows.Storage.FileProperties.ThumbnailMode,unsigned int) M:Windows.Storage.IStorageItemProperties.GetThumbnailAsync(Windows.Storage.FileProperties.ThumbnailMode,uint32_t)
Attributes
OverloadAttribute RemoteAsyncAttribute

Remarks

While GetThumbnailAsync adheres to the max size supported by the thumbnail disk cache, GetScaledImageAsThumbnailAsync can extract thumbnails that are larger than what the thumbnail disk cache supports. GetScaledImageAsThumbnailAsync provides optimal quality but can affect performance by not using the disk cache if the thumbnail size is too large.

See also

Applies to