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interface ICoreWebView2DownloadOperation

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interface ICoreWebView2DownloadOperation
  : public IUnknown

Represents a download operation.

Summary

Members Descriptions
add_BytesReceivedChanged Add an event handler for the BytesReceivedChanged event.
add_EstimatedEndTimeChanged Add an event handler for the EstimatedEndTimeChanged event.
add_StateChanged Add an event handler for the StateChanged event.
Cancel Cancels the download.
get_BytesReceived The number of bytes that have been written to the download file.
get_CanResume Returns true if an interrupted download can be resumed.
get_ContentDisposition The Content-Disposition header value from the download's HTTP response.
get_EstimatedEndTime The estimated end time in ISO 8601 Date and Time Format.
get_InterruptReason The reason why connection with file host was broken.
get_MimeType MIME type of the downloaded content.
get_ResultFilePath The absolute path to the download file, including file name.
get_State The state of the download.
get_TotalBytesToReceive The expected size of the download in total number of bytes based on the HTTP Content-Length header.
get_Uri The URI of the download.
Pause Pauses the download.
remove_BytesReceivedChanged Remove an event handler previously added with add_BytesReceivedChanged.
remove_EstimatedEndTimeChanged Remove an event handler previously added with add_EstimatedEndTimeChanged.
remove_StateChanged Remove an event handler previously added with add_StateChanged.
Resume Resumes a paused download.

Gives access to the download's metadata and supports a user canceling, pausing, or resuming the download.

Applies to

Product Introduced
WebView2 Win32 1.0.902.49
WebView2 Win32 Prerelease 1.0.902

Members

add_BytesReceivedChanged

Add an event handler for the BytesReceivedChanged event.

public HRESULT add_BytesReceivedChanged(ICoreWebView2BytesReceivedChangedEventHandler * eventHandler, EventRegistrationToken * token)

    CHECK_FAILURE(download->add_BytesReceivedChanged(
        Callback<ICoreWebView2BytesReceivedChangedEventHandler>(
            [this](ICoreWebView2DownloadOperation* download, IUnknown* args) -> HRESULT {
                // Here developer can update UI to show progress of a download using
                // `download->get_BytesReceived` and
                // `download->get_TotalBytesToReceive`.
                return S_OK;
            })
            .Get(),
        &m_bytesReceivedChangedToken));

add_EstimatedEndTimeChanged

Add an event handler for the EstimatedEndTimeChanged event.

public HRESULT add_EstimatedEndTimeChanged(ICoreWebView2EstimatedEndTimeChangedEventHandler * eventHandler, EventRegistrationToken * token)

add_StateChanged

Add an event handler for the StateChanged event.

public HRESULT add_StateChanged(ICoreWebView2StateChangedEventHandler * eventHandler, EventRegistrationToken * token)

    CHECK_FAILURE(download->add_StateChanged(
        Callback<ICoreWebView2StateChangedEventHandler>(
          [this](ICoreWebView2DownloadOperation* download,
            IUnknown* args) -> HRESULT {
                COREWEBVIEW2_DOWNLOAD_STATE downloadState;
                CHECK_FAILURE(download->get_State(&downloadState));
                switch (downloadState)
                {
                case COREWEBVIEW2_DOWNLOAD_STATE_IN_PROGRESS:
                    break;
                case COREWEBVIEW2_DOWNLOAD_STATE_INTERRUPTED:
                    // Here developer can take different actions based on `download->InterruptReason`.
                    // For example, show an error message to the end user.
                    CompleteDownload(download);
                    break;
                case COREWEBVIEW2_DOWNLOAD_STATE_COMPLETED:
                    CompleteDownload(download);
                    break;
                }
                return S_OK;
          })
          .Get(),
        &m_stateChangedToken));

Cancel

Cancels the download.

public HRESULT Cancel()

If canceled, the default download dialog shows that the download was canceled. Host should set the Cancel property from ICoreWebView2SDownloadStartingEventArgs if the download should be canceled without displaying the default download dialog.

get_BytesReceived

The number of bytes that have been written to the download file.

public HRESULT get_BytesReceived(INT64 * bytesReceived)

get_CanResume

Returns true if an interrupted download can be resumed.

public HRESULT get_CanResume(BOOL * canResume)

Downloads with the following interrupt reasons may automatically resume without you calling any methods: COREWEBVIEW2_DOWNLOAD_INTERRUPT_REASON_SERVER_NO_RANGE, COREWEBVIEW2_DOWNLOAD_INTERRUPT_REASON_FILE_HASH_MISMATCH, COREWEBVIEW2_DOWNLOAD_INTERRUPT_REASON_FILE_TOO_SHORT. In these cases download progress may be restarted with BytesReceived reset to 0.

get_ContentDisposition

The Content-Disposition header value from the download's HTTP response.

public HRESULT get_ContentDisposition(LPWSTR * contentDisposition)

The caller must free the returned string with CoTaskMemFree. See API Conventions.

get_EstimatedEndTime

The estimated end time in ISO 8601 Date and Time Format.

public HRESULT get_EstimatedEndTime(LPWSTR * estimatedEndTime)

The caller must free the returned string with CoTaskMemFree. See API Conventions.

get_InterruptReason

The reason why connection with file host was broken.

public HRESULT get_InterruptReason(COREWEBVIEW2_DOWNLOAD_INTERRUPT_REASON * interruptReason)

get_MimeType

MIME type of the downloaded content.

public HRESULT get_MimeType(LPWSTR * mimeType)

The caller must free the returned string with CoTaskMemFree. See API Conventions.

get_ResultFilePath

The absolute path to the download file, including file name.

public HRESULT get_ResultFilePath(LPWSTR * resultFilePath)

Host can change this from ICoreWebView2DownloadStartingEventArgs.

The caller must free the returned string with CoTaskMemFree. See API Conventions.

get_State

The state of the download.

public HRESULT get_State(COREWEBVIEW2_DOWNLOAD_STATE * downloadState)

A download can be in progress, interrupted, or completed. See COREWEBVIEW2_DOWNLOAD_STATE for descriptions of states.

get_TotalBytesToReceive

The expected size of the download in total number of bytes based on the HTTP Content-Length header.

public HRESULT get_TotalBytesToReceive(INT64 * totalBytesToReceive)

Returns -1 if the size is unknown.

get_Uri

The URI of the download.

public HRESULT get_Uri(LPWSTR * uri)

The caller must free the returned string with CoTaskMemFree. See API Conventions.

Pause

Pauses the download.

public HRESULT Pause()

If paused, the default download dialog shows that the download is paused. No effect if download is already paused. Pausing a download changes the state to COREWEBVIEW2_DOWNLOAD_STATE_INTERRUPTED with InterruptReason set to COREWEBVIEW2_DOWNLOAD_INTERRUPT_REASON_USER_PAUSED.

remove_BytesReceivedChanged

Remove an event handler previously added with add_BytesReceivedChanged.

public HRESULT remove_BytesReceivedChanged(EventRegistrationToken token)

remove_EstimatedEndTimeChanged

Remove an event handler previously added with add_EstimatedEndTimeChanged.

public HRESULT remove_EstimatedEndTimeChanged(EventRegistrationToken token)

remove_StateChanged

Remove an event handler previously added with add_StateChanged.

public HRESULT remove_StateChanged(EventRegistrationToken token)

Resume

Resumes a paused download.

public HRESULT Resume()

May also resume a download that was interrupted for another reason, if CanResume returns true. Resuming a download changes the state from COREWEBVIEW2_DOWNLOAD_STATE_INTERRUPTED to COREWEBVIEW2_DOWNLOAD_STATE_IN_PROGRESS.