Subroutine

Send data to the client.

 

call DDEDataString ( ConvID_IV, ItemName_SV, DataString_SV, DataLength_IV, Format_SV, Status_IV)

 

•ConvID_IV is an integer value representing the conversation ID assigned by the DDE DLL.

•ItemName_SV is a string value representing the item name.  ItemName_SV should contain the same name that was requested by the client.

•DataString_SV is a string value representing the data string being sent to the client.  The string can be zero-length only for data sent as part of an ongoing advise state initiated with DDE_FNODATA.

•DataLength_IV is an integer value representing the length of the data string.

•Format_SV is a string value.  Format_SV should be the same format requested by the client.

•Status_IV is composed of DDE_FACKREQ and DDE_FRESPONSE status flags. The DDE protocol defines the DDE_FACKREQ and DDE_FRESPONSE status flags for this subroutine as follows:

 

•The DDE_FRESPONSE status flag should be set if this data is being sent in response to a WM_DDE_REQUEST.  It is cleared if this data is being sent as part of an ongoing advise state.  (See the DDEAdvise subroutine for more information.)

•The DDE_FACKREQ status flag should be set if the application wants the receiving partner to acknowledge receipt of the data. (The DDE DLL will invoke a DDE_ACK event when the partner does this.)  If this data is being sent as part of an ongoing advise state, this flag should be set if the client requested that it be set when the advise state was established.  (See DDE_ADVISE.)

Description

Called by the server.  This subroutine sends data to the client. DDEDataString should be called only in response to a DDE_REQUEST event or as part of an ongoing DDE_ADVISE event.

 

Upon receipt of data, the DDE protocol requires that the client responds as follows if the DDE_FACKREQ status flag is set.  The server should not attempt another DDE exchange for this conversation until the client has responded with one of these events.

Message

Posts a WM_DDE_DATA message to the client partner.

Example

response to stimulus DDE DDE_REQUEST

    copy eventparam to ConvID_IV

    copy DDEGetItemName (ConvID_IV) to ItemName_SV

    copy DDEGetFormat (ConvID_IV) to Format_DV

    if (GetTheData (ItemName_SV, Format_SV, DataString_SV))

        copy (length of DataString_SV) to DataLength_IV

        copy DDESetStatusFlag (0, DDE_FACKREQ) to Status_IV

        copy DDESetStatusFlag (Status_IV, DDE_FRESPONSE)

             to Status_IV

        call DDEDataString (ConvID_IV, ItemName_SV, DataString_SV,

                            DataLength_IV, Format_SV, Status_IV)

    else

        copy 0 to Status_IV            # Send a negative ACK

        call DDEAck (ConvID_IV, ItemName_SV, Format_SV, Status_IV)

    end if

 

response to stimulus DDE DDE_ACK     # Recognize the

    copy true to StatusOK_BV         # acknowledgment

 

#  This code fragment is assumed to be running in a

#  server.  This code is called because of a change in

#  data and is used to inform the client, which had

#  previously sent an advise for this data.

 

    copy (length of AdviseDataString_SV) to DataLength_IV

    copy 0 to Status_IV

    if (AdviseAckRequested) then

        copy (DDESetStatusFlag

                (Status_IV, DDE_FACKREQ)) to Status_IV

    end if

    call DDEDataString(AdviseConvID_IV, AdviseItemName_SV,

                       AdviseDataString_SV, DataLength_IV,

                       AdviseFormat_SV, Status_IV)