Solved

CRecordset and CLongBinary (BLOB problem)

Posted on 1998-08-20
3
1,185 Views
Last Modified: 2013-11-20
How do I store a blob through ODBC !
I got a CLongBinary object in a derived CRecordset and a BMP-file on disk.
1. - How do I load the BMP into the CLongBinary-object
2. - Does the CLongBinary automaticly get into the base on CRecordset.update() ?
Codesample please !!

0
Comment
Question by:Jeb
  • 2
3 Comments
 

Accepted Solution

by:
MURALI_YAKKALI earned 80 total points
ID: 1321090
First you have to copy BMP file into CLongBinary object.
you can do this by
Here
 strFileName = BMP file name
 BinaryObj   =  long binary object

:: int  LoadBlobFromFile(CString& strFileName,CLongBinary* BinaryObj)
{

      CFile            blobFile(NULL);
      DWORD            FileLth;
      void*            lVoidPtr = NULL;

      if(blobFile.Open(strFileName,CFile::typeBinary | CFile::modeRead))
      {

            FileLth = blobFile.GetLength();
      
            BinaryObj->m_hData = GlobalAlloc(0,FileLth);
            BinaryObj->m_dwDataLength = FileLth;

            lVoidPtr = GlobalLock(BinaryObj->m_hData);
            DWORD lTemp = blobFile.ReadHuge(lVoidPtr,FileLth);
            GlobalUnlock(BinaryObj->m_hData);
            strFileName = blobFile.GetFileName();
            blobFile.Close();
            return SUCCESS;

      }
      else
            return FAILURE;

} // End of LoadBlobFromFile

After loading bmp into longbinary you have to store this into database
You can do this by
DWORD i,dwSize;
BYTE* lpdstbyte = NULL;
BYTE* lpsrcbyte = NULL;
int :: AddnewRecord(CLongBinary* pDataObj)
{
      try
      {
            if(!IsOpen())
              Open();
            AddNew();  

      if(pDataObj.m_hData && ::GlobalSize(m_DataObj.m_hData))
      {
            ::GlobalFree(m_DataObj.m_hData);
            m_DataObj.m_hData = NULL;
            m_DataObj.m_dwDataLength = 0;
      }

      dwSize = pDataObj.m_dwDataLength;
      m_DataObj.m_hData  = GlobalAlloc(0,dwSize);

      lpdstbyte = (BYTE*)GlobalLock(m_DataObj.m_hData);
      if(lpdstbyte == NULL)
            return *this;

      lpsrcbyte = (BYTE*)GlobalLock(pDataObj.m_hData);
      if(lpsrcbyte == NULL)
      {
            GlobalUnlock(m_DataObj.m_hData);
                return;
      }

      for(i=0; i< dwSize; i++)
      {
            lpdstbyte[i] = lpsrcbyte[i];
      }

      m_DataObj.m_dwDataLength   =  dwSize;

      GlobalUnlock(m_DataObj.m_hData);
      GlobalUnlock(pDataObj.m_hData);
                                       
        SetFieldDirty(&m_DataObj,TRUE);                                    
        SetFieldNull(&m_DataObj,FALSE);      
      Update();
      Close();
        return SUCCESS;

      }
      catch(CDBException* fe)
      {
            return FAILURE;
      }

}

This is complete code for storing blob intodatabase.
Hope this will help U!!


0
 

Author Comment

by:Jeb
ID: 1321091
You saved my holiday :)
0
 

Author Comment

by:Jeb
ID: 1321092
It should have been 80 points instead of 8 !!  sorry
0

Featured Post

DevOps Toolchain Recommendations

Read this Gartner Research Note and discover how your IT organization can automate and optimize DevOps processes using a toolchain architecture.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
Macro to save highlighted rows as a separate file 5 43
Tab names are off by one 5 54
modThree challenge 4 91
Annoying "thing" blocks my view 4 100
Introduction: Dynamic window placements and drawing on a form, simple usage of windows registry as a storage place for information. Continuing from the first article about sudoku.  There we have designed the application and put a lot of user int…
Introduction: Dialogs (2) modeless dialog and a worker thread.  Handling data shared between threads.  Recursive functions. Continuing from the tenth article about sudoku.   Last article we worked with a modal dialog to help maintain informat…
This video will show you how to get GIT to work in Eclipse.   It will walk you through how to install the EGit plugin in eclipse and how to checkout an existing repository.

803 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question