CachedFileUpdater 类

定义

命名空间:

Windows.Storage.Provider

管理文件，以便参与缓存文件更新程序合约的应用可以实时更新文件。

public ref class CachedFileUpdater abstract sealed

/// [Windows.Foundation.Metadata.ContractVersion(Windows.Foundation.UniversalApiContract, 65536)]
/// [Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
class CachedFileUpdater final

[Windows.Foundation.Metadata.ContractVersion(typeof(Windows.Foundation.UniversalApiContract), 65536)]
[Windows.Foundation.Metadata.MarshalingBehavior(Windows.Foundation.Metadata.MarshalingType.Agile)]
public static class CachedFileUpdater

Public Class CachedFileUpdater

继承

Object Platform::Object IInspectable CachedFileUpdater

属性

ContractVersionAttribute MarshalingBehaviorAttribute

Windows 要求

设备系列	Windows 10 (在 10.0.10240.0 - for Xbox, see UWP features that aren't yet supported on Xbox 中引入)
API contract	Windows.Foundation.UniversalApiContract (在 v1.0 中引入)

示例

文件选取器协定示例演示如何在其 TargetFileRequested 事件处理程序中设置文件的更新信息。

private async void OnTargetFileRequested(FileSavePickerUI sender, TargetFileRequestedEventArgs e)
{
    // Handle the TargetFileRequested event on the background thread on which it was raised

    // Requesting a deferral allows the app to call another asynchronous method and complete the request at a later time
    var deferral = e.Request.GetDeferral();

    StorageFile file = await ApplicationData.Current.LocalFolder.CreateFileAsync(sender.FileName, CreationCollisionOption.ReplaceExisting);

    // Set update info for the file
    CachedFileUpdater.SetUpdateInformation(file, "CachedFile", ReadActivationMode.NotNeeded, WriteActivationMode.AfterWrite, CachedFileOptions.RequireUpdateOnAccess);

    // Assign the resulting file to the targetFile property and complete the deferral to indicate success  
    e.Request.TargetFile = file;
    deferral.Complete();
}

注解

静态访问此类中的方法。

方法

SetUpdateInformation(IStorageFile, String, ReadActivationMode, WriteActivationMode, CachedFileOptions)

为本地文件配置更新策略。

另请参阅

• 文件选取器协定示例