共用方式為

INTERNET_STATUS_CALLBACK

  • 發行項

A version of this page is also available for

Windows Embedded CE 6.0 R3

4/8/2010

This function is a prototype for an application-defined status callback function.

Syntax

typedef void (CALLBACK* INTERNET_STATUS_CALLBACK) (
  HINTERNET hInternet,
  DWORD_PTR dwContext,
  DWORD dwInternetStatus,
  LPVOID lpvStatusInformation,
  DWORD dwStatusInformationLength
);

Parameters

  • hInternet
    [in] Handle for which the callback function is being called.
  • dwContext
    [in] Address of an unsigned long integer value that contains the application-defined context value associated with the hInternet parameter.

  • dwInternetStatus
    [in] Unsigned long integer value that contains the status code that indicates why the callback function is being called. The following table shows the values for this parameter.

    Value Description

    INTERNET_STATUS_CLOSING_CONNECTION

    Closing the connection to the server. The lpvStatusInformation parameter is NULL.

    INTERNET_STATUS_CONNECTED_TO_SERVER

    Successfully connected to the socket address (SOCKADDR) pointed to by lpvStatusInformation.

    INTERNET_STATUS_CONNECTING_TO_SERVER

    Connecting to the socket address (SOCKADDR) pointed to by the lpvStatusInformation parameter.

    INTERNET_STATUS_CONNECTION_CLOSED

    Successfully closed the connection to the server. The lpvStatusInformation parameter is NULL.

    INTERNET_STATUS_CTL_RESPONSE_RECEIVED

    Not implemented.

    INTERNET_STATUS_DETECTING_PROXY

    Notifies the client application that a proxy has been detected.

    INTERNET_STATUS_HANDLE_CLOSING

    This handle value has been terminated.

    INTERNET_STATUS_HANDLE_CREATED

    Used by the InternetConnect function to indicate it has created the new handle. This allows the application call the InternetCloseHandle function from another thread, if the connect is taking too long. The lpvStatusInformation parameter contains the address of an INTERNET_ASYNC_RESULT structure.

    INTERNET_STATUS_INTERMEDIATE_RESPONSE

    Received an intermediate (100 level) status code message from the server.

    INTERNET_STATUS_NAME_RESOLVED

    Successfully found the IP address of the name contained in the lpvStatusInformation parameter.

    INTERNET_STATUS_PREFETCH

    Not implemented.

    INTERNET_STATUS_RECEIVING_RESPONSE

    Waiting for the server to respond to a request. The lpvStatusInformation parameter is NULL.

    INTERNET_STATUS_REDIRECT

    An HTTP request is about to automatically redirect the request. The lpvStatusInformation parameter points to the new URL. At this point, the application can read any data returned by the server with the redirect response and can query the response headers. It can also cancel the operation by closing the handle. This callback is not made if the original request specified INTERNET_FLAG_NO_AUTO_REDIRECT.

    INTERNET_STATUS_REQUEST_COMPLETE

    An asynchronous operation has been completed. The lpvStatusInformation parameter contains the address of an INTERNET_ASYNC_RESULT structure.

    INTERNET_STATUS_REQUEST_SENT

    Successfully sent the information request to the server. The lpvStatusInformation parameter points to a DWORD containing the number of bytes sent.

    INTERNET_STATUS_RESOLVING_NAME

    Looking up the IP address of the name contained in the lpvStatusInformation parameter.

    INTERNET_STATUS_RESPONSE_RECEIVED

    Successfully received a response from the server. The lpvStatusInformation parameter points to a DWORD containing the number of bytes received.

    INTERNET_STATUS_SENDING_REQUEST

    Sending the information request to the server. The lpvStatusInformation parameter is NULL.

    INTERNET_STATUS_SSL_NEGOTIATION_COMPLETE

    Indicates that the SSL negotiation was successful.

    INTERNET_STATUS_STATE_CHANGE

    Moved between a secure (HTTPS) site and a nonsecure (HTTP) site. The following list shows the possible values. This can be one of these values:

    • INTERNET_STATE_CONNECTED
      Connected state (mutually exclusive with disconnected state).
    • INTERNET_STATE_DISCONNECTED
      Disconnected state. No network connection could be established.
    • INTERNET_STATE_DISCONNECTED_BY_USER
      Disconnected by user request.
    • INTERNET_STATE_IDLE
      No network requests are being made by the WinInet functions.
    • INTERNET_STATE_BUSY
      Network requests are being made by the WinInet functions.
    • INTERNET_STATUS_USER_INPUT_REQUIRED
      The request requires user input to be completed.
  • lpvStatusInformation
    [in] Address of a buffer that contains information pertinent to this call to the callback function.
  • dwStatusInformationLength
    [in] Unsigned long integer value that contains the size, in TCHARs, of the lpvStatusInformation buffer.

Return Value

None.

Remarks

Because callbacks are made during processing of the request, the application should spend as little time as possible in the callback function to avoid degrading data throughput on the network. For example, displaying a dialog box in a callback function can be such a lengthy operation that the server terminates the request.

The callback function can be called in a thread context different from the thread that initiated the request.

Requirements

Header Developer Implemented
Windows Embedded CE Windows CE 2.12 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also

Reference

InternetConnect
InternetCloseHandle
INTERNET_ASYNC_RESULT
WinInet Functions