StorageFile.CopyAsync 方法

定义

命名空间:

Windows.Storage

重载

CopyAsync(IStorageFolder)	在指定文件夹中创建文件的副本。
CopyAsync(IStorageFolder, String)	在指定文件夹中创建文件的副本，并重命名该副本。
CopyAsync(IStorageFolder, String, NameCollisionOption)	在指定文件夹中创建文件的副本，并重命名该副本。 此方法还指定在目标文件夹中已存在同名文件时要执行的操作。

CopyAsync(IStorageFolder)

在指定文件夹中创建文件的副本。

public:
 virtual IAsyncOperation<StorageFile ^> ^ CopyAsync(IStorageFolder ^ destinationFolder) = CopyAsync;

/// [Windows.Foundation.Metadata.Overload("CopyOverloadDefaultNameAndOptions")]
/// [Windows.Foundation.Metadata.RemoteAsync]
IAsyncOperation<StorageFile> CopyAsync(IStorageFolder const& destinationFolder);

[Windows.Foundation.Metadata.Overload("CopyOverloadDefaultNameAndOptions")]
[Windows.Foundation.Metadata.RemoteAsync]
public IAsyncOperation<StorageFile> CopyAsync(IStorageFolder destinationFolder);

function copyAsync(destinationFolder)

Public Function CopyAsync (destinationFolder As IStorageFolder) As IAsyncOperation(Of StorageFile)

参数

destinationFolder

IStorageFolder

在其中创建文件副本的目标文件夹。

返回

IAsyncOperation<StorageFile>

此方法完成后，它将返回一个 StorageFile ，表示在 destinationFolder 中创建的文件的副本。

实现

CopyAsync(IStorageFolder)

属性

OverloadAttribute RemoteAsyncAttribute

例外

UnauthorizedAccessException

您没有将文件复制到目标文件夹的权限。

示例

以下示例将文件复制到指定文件夹，并通过调用 CopyAsync (IStorageFolder、String、NameCollisionOption) 方法重命名副本。 此示例显式为 选项 指定一个值，如果已存在具有指定名称的文件，则替换目标文件夹中的文件。

using Windows.Storage;
using System.Threading.Tasks;

// Get the app's temporary folder.
StorageFolder tempFolder = ApplicationData.Current.TemporaryFolder;

// Create a sample file in the temporary folder.
string newFileName = "test.txt";
StorageFile newFile = await tempFolder.CreateFileAsync(newFileName);

// Get the app's local folder to use as the destination folder.
StorageFolder localFolder = ApplicationData.Current.LocalFolder;

// Specify a new name for the copied file.
string renamedFileName = "renamed_test.txt";

// Copy the file to the destination folder and rename it.
// Replace the existing file if the file already exists.
StorageFile copiedFile = await newFile.CopyAsync(localFolder, renamedFileName, NameCollisionOption.ReplaceExisting);

IAsyncAction MainPage::CopyFileAsync()
{
    // Get the app's temporary folder.
    StorageFolder sourceFolder{ ApplicationData::Current().TemporaryFolder() };
    StorageFolder targetFolder{ ApplicationData::Current().LocalFolder() };

    // Choose source file name and new name for the copied file.
    std::wstring newFileName{ L"test.txt" };
    std::wstring copyFileName{ L"renamed_test.txt" };

    // Create a sample file in the temporary folder.
    StorageFile sourceFile{ co_await sourceFolder.CreateFileAsync(newFileName, Windows::Storage::CreationCollisionOption::ReplaceExisting) };
    // Overwrite any existing file with the same name.
    StorageFile copiedFile{ co_await sourceFile.CopyAsync(targetFolder, copyFileName, Windows::Storage::NameCollisionOption::ReplaceExisting) };
    // Do something with copied file.
}

//Get the app's temporary folder
StorageFolder^ sourceFolder = ApplicationData::Current->TemporaryFolder;
StorageFolder^ targetFolder = ApplicationData::Current->LocalFolder;

// Choose source file name and new name for the copied file
String^ newFileName = "test.txt";
String^ copyFileName = "renamed_test.txt";

//Create a sample file in the temporary folder
auto copyFileTask = create_task(sourceFolder->CreateFileAsync(newFileName, Windows::Storage::CreationCollisionOption::ReplaceExisting)).then
([targetFolder, copyFileName](StorageFile^ sourceFile) -> task<StorageFile^>
{
    //Overwrite any existing file with the same name 
    auto copyFileTask = sourceFile->CopyAsync(targetFolder, copyFileName, Windows::Storage::NameCollisionOption::ReplaceExisting);
    return create_task(copyFileTask);
}).then([](StorageFile^ copiedFile) {
    //do something with copied file
});

注解

默认情况下，此方法使用 CreationCollisionOption 枚举中的 FailIfExists 值。 也就是说，如果目标文件夹中已存在同名的文件，此方法将引发异常。 如果要以其他方式处理文件名冲突，请调用 CopyAsync (IStorageFolder、String、NameCollisionOption) 重载方法。

注意

使用 StorageFile.CopyAsync 将加密的文件复制到未加密的目标时，调用将失败，并出现以下异常： System.UnauthorizedAccessException: Access is denied. (Excep_FromHResult 0x80070005)

另请参阅

• CopyAsync(IStorageFolder, String)
• CopyAsync(IStorageFolder, String, NameCollisionOption)

CopyAsync(IStorageFolder, String)

在指定文件夹中创建文件的副本，并重命名该副本。

public:
 virtual IAsyncOperation<StorageFile ^> ^ CopyAsync(IStorageFolder ^ destinationFolder, Platform::String ^ desiredNewName) = CopyAsync;

/// [Windows.Foundation.Metadata.Overload("CopyOverloadDefaultOptions")]
/// [Windows.Foundation.Metadata.RemoteAsync]
IAsyncOperation<StorageFile> CopyAsync(IStorageFolder const& destinationFolder, winrt::hstring const& desiredNewName);

[Windows.Foundation.Metadata.Overload("CopyOverloadDefaultOptions")]
[Windows.Foundation.Metadata.RemoteAsync]
public IAsyncOperation<StorageFile> CopyAsync(IStorageFolder destinationFolder, string desiredNewName);

function copyAsync(destinationFolder, desiredNewName)

Public Function CopyAsync (destinationFolder As IStorageFolder, desiredNewName As String) As IAsyncOperation(Of StorageFile)

参数

destinationFolder

IStorageFolder

在其中创建文件副本的目标文件夹。

desiredNewName

String

Platform::String

winrt::hstring

在 destinationFolder 中创建的文件副本的新名称。

返回

IAsyncOperation<StorageFile>

此方法完成后，它将返回一个 StorageFile ，表示在 destinationFolder 中创建的文件的副本。

注意

使用 StorageFile.CopyAsync 将加密的文件复制到未加密的目标时，调用将失败，并出现以下异常： System.UnauthorizedAccessException: Access is denied. (Excep_FromHResult 0x80070005)

实现

M:Windows.Storage.IStorageFile.CopyAsync(Windows.Storage.IStorageFolder,System.String) M:Windows.Storage.IStorageFile.CopyAsync(Windows.Storage.IStorageFolder,Platform::String) M:Windows.Storage.IStorageFile.CopyAsync(Windows.Storage.IStorageFolder,winrt::hstring)

属性

OverloadAttribute RemoteAsyncAttribute

例外

UnauthorizedAccessException

您没有将文件复制到目标文件夹的权限。

另请参阅

• CopyAsync(IStorageFolder)
• CopyAsync(IStorageFolder, String, NameCollisionOption)

CopyAsync(IStorageFolder, String, NameCollisionOption)

在指定文件夹中创建文件的副本，并重命名该副本。 此方法还指定在目标文件夹中已存在同名文件时要执行的操作。

public:
 virtual IAsyncOperation<StorageFile ^> ^ CopyAsync(IStorageFolder ^ destinationFolder, Platform::String ^ desiredNewName, NameCollisionOption option) = CopyAsync;

/// [Windows.Foundation.Metadata.Overload("CopyOverload")]
/// [Windows.Foundation.Metadata.RemoteAsync]
IAsyncOperation<StorageFile> CopyAsync(IStorageFolder const& destinationFolder, winrt::hstring const& desiredNewName, NameCollisionOption const& option);

[Windows.Foundation.Metadata.Overload("CopyOverload")]
[Windows.Foundation.Metadata.RemoteAsync]
public IAsyncOperation<StorageFile> CopyAsync(IStorageFolder destinationFolder, string desiredNewName, NameCollisionOption option);

function copyAsync(destinationFolder, desiredNewName, option)

Public Function CopyAsync (destinationFolder As IStorageFolder, desiredNewName As String, option As NameCollisionOption) As IAsyncOperation(Of StorageFile)

参数

destinationFolder

IStorageFolder

在其中创建文件副本的目标文件夹。

desiredNewName

String

Platform::String

winrt::hstring

在 destinationFolder 中创建的文件副本的新名称。

option

NameCollisionOption

如果目标文件夹中已存在具有指定 desiredNewName 的文件，则确定如何处理冲突的枚举值之一。

返回

IAsyncOperation<StorageFile>

此方法完成后，它将返回一个 StorageFile ，表示在 destinationFolder 中创建的文件的副本。

注意

使用 StorageFile.CopyAsync 将加密的文件复制到未加密的目标时，调用将失败，并出现以下异常： System.UnauthorizedAccessException: Access is denied. (Excep_FromHResult 0x80070005)

实现

M:Windows.Storage.IStorageFile.CopyAsync(Windows.Storage.IStorageFolder,System.String,Windows.Storage.NameCollisionOption) M:Windows.Storage.IStorageFile.CopyAsync(Windows.Storage.IStorageFolder,Platform::String,Windows.Storage.NameCollisionOption) M:Windows.Storage.IStorageFile.CopyAsync(Windows.Storage.IStorageFolder,winrt::hstring,Windows.Storage.NameCollisionOption)

属性

OverloadAttribute RemoteAsyncAttribute

例外

UnauthorizedAccessException

您没有将文件复制到目标文件夹的权限。

另请参阅

• CopyAsync(IStorageFolder)
• CopyAsync(IStorageFolder, String)