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POHow to be notified of any update from Dynamic Data Exchange (DDE)?
 

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  1. POHow to be notified of any update from Dynamic Data Exchange (DDE)?
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    <p>I was following the example from <a href="http://support.microsoft.com/kb/279721" rel="nofollow noreferrer">How to use Dynamic Data Exchange (DDE) with Word and Excel from Visual C++</a> and I somehow managed to able able to retrieve the value from the Excel.</p> <p>Now the question is, with this example, I have to run the application over again to get the necessary update. How do I make it in such a way that if there is an update in Excel, my application will be notified? DdeAdvise?</p> <p>Thanks in advance! Excel is just an example! And no, I need DDE not COM even if its old.</p> <pre><code>// DDEExample.cpp : Defines the entry point for the console application. // #include "stdafx.h" #include &lt;windows.h&gt; #include "ddeml.h" #define PAUSE system("pause") HDDEDATA CALLBACK DdeCallback(UINT uType, UINT uFmt, HCONV hconv, HSZ hsz1, HSZ hsz2, HDDEDATA hdata, ULONG_PTR dwData1, ULONG_PTR dwData2) { printf("uType: %d", uType); switch(uType) { case XTYP_REQUEST: printf("XTYP_REQUEST\n"); break; } return 0; } void DDERequest(DWORD idInst, HCONV hConv, char* szItem, char* sDesc) { HSZ hszItem = DdeCreateStringHandle(idInst, szItem, 0); HDDEDATA hData = DdeClientTransaction(NULL,0,hConv,hszItem,CF_TEXT, XTYP_REQUEST,5000 , NULL); if (hData==NULL) { printf("Request failed: %s\n", szItem); } else { char szResult[255]; DdeGetData(hData, (unsigned char *)szResult, 255, 0); printf("%s%s\n", sDesc, szResult); } } int _tmain(int argc, _TCHAR* argv[]) { char szApp[] = "EXCEL"; char szTopic[] = "C:\\Test.xlsx"; char szCmd1[] = "[APP.MINIMIZE()]"; char szItem1[] = "R1C1"; char szDesc1[] = "A1 Contains: "; UINT uiResult; DWORD m_dwDDEInstance = 0; uiResult = DdeInitialize(&amp;m_dwDDEInstance, (PFNCALLBACK) &amp;DdeCallback, APPCLASS_STANDARD|APPCMD_CLIENTONLY, 0); if(uiResult != DMLERR_NO_ERROR) { printf("DDE Initialization Failed: 0x%04x\n", uiResult); return FALSE; } printf("m_dwDDEInstance: %u\n", m_dwDDEInstance); //PAUSE; HSZ hszApp, hszTopic; HCONV hConv; hszApp = DdeCreateStringHandle(m_dwDDEInstance, szApp, 0); hszTopic = DdeCreateStringHandle(m_dwDDEInstance, szTopic, 0); hConv = DdeConnect(m_dwDDEInstance, hszApp, hszTopic, NULL); DdeFreeStringHandle(m_dwDDEInstance, hszApp); DdeFreeStringHandle(m_dwDDEInstance, hszTopic); if(hConv == NULL) { printf("DDE Connection Failed.\n"); } DDERequest(m_dwDDEInstance, hConv, szItem1, szDesc1); DdeDisconnect(hConv); DdeUninitialize(m_dwDDEInstance); PAUSE; } </code></pre>
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    1. USuser303907
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      1. POHow to be notified of any update from Dynamic Data Exchange (DDE)?
      1. USJerry Coffin
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    1. COIs there some compelling reason to use DDE instead of Automation?
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      1. POHow to be notified of any update from Dynamic Data Exchange (DDE)?
      1. USMarcelo Cantos
    2. CO@Marcelo Cantos Hello, thanks for the reply. DDE is the only option that is being offered by the application for communication and I think DDE is rather "open" for app<->app communication.
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      1. POHow to be notified of any update from Dynamic Data Exchange (DDE)?
      1. USuser303907
    3. CO@user303907: DDE is a buggy mess. Do NOT use it. Research any other possible solution, e.g. OLE. Otherwise, I do not think Office has notification on user input.
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      1. USDummy00001
 

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