PRB: Cannot Manipulate Columns of MS DataGrid in Visual C++ at Design Time (225065)

RESOLUTION

You can manipulate the columns of DataGrid programmatically at run time. The sample code below shows how to add/remove a column, and modify the column's caption when using ADO data control and DataGrid with an MFC CVCDataGridDlg class.

Insert the following variables and member function prototypes in the corresponding dialog class declaration:

• CDataGrid m_Grid; // DataGrid variable.
• CAdodc m_DataControl; // ADO Data Control variable.
• void OnAdd( ) // Function for adding a column.
• void OnRemove( ) // Function for removing a column.
• void OnModify( ) // Function for modifying a column.

Sample Code

//implementation
#include "columns.h"    // CColumns collection object header file.
#include "column.h"     // CColumn object header file.
#include "_recordset.h" // C_Recordset object header file.
#include "fields.h"     // CFields collection object header file.
#include "field.h"      // CFields object header file.
#include <comdef.h>

// Adding a column.	
void CVCDataGridDlg::OnAdd() 
{
   //Get the total number of columns.
   short i = (short)(m_DataGrid.GetColumns().GetCount());<BR/>
   //Insert the new column.
   m_DataGrid.GetColumns().Add(i);
   CString rCaption;
   GetDlgItemText(IDC_EDIT2,rCaption);
   //Set the caption of the column.
  m_DataGrid.GetColumns().GetItem(_variant_t(i)).SetCaption((LPCTSTR)rCaption);
  m_DataGrid.Refresh();
}

// Removing a column.
void CVCDataGridDlg::OnRemove() 
{
   m_DataGrid.GetColumns().Remove( _variant_t((long) atoi(m_Edit.GetBuffer(m_Caption.GetLength()) )));
   m_DataGrid.Refresh();
}

// Modifying a column caption.
void CVCDataGridDlg::OnModify() 
{
   CString rCaption, rColNum;
   GetDlgItemText(IDC_EDIT1,rColNum);
   GetDlgItemText(IDC_EDIT2,rCaption);
   m_DataGrid.GetColumns().GetItem(_variant_t((long) atoi(rColNum))).SetCaption((LPCTSTR) rCaption);<BR/>
   m_DataGrid.Refresh();
}