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Example using ado

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TimoVJL:
This is just an example using ado

--- Code: ---#define UNICODE
#define _UNICODE
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#define INITGUID
#include <ole2.h>
#include <stdio.h>
#include <tchar.h>

#include "msado15.h"

#pragma comment(lib, "user32.lib")
#pragma comment(lib, "ole32.lib")
#pragma comment(lib, "oleaut32.lib")

TCHAR *GetADOErrorCode(DWORD nErr);

int main(int argc, char **argv)
{
HRESULT hr;
Recordset15 *pRst = NULL;

hr = CoInitialize(NULL);
hr = CoCreateInstance(&CLSID_Recordset, NULL, CLSCTX_ALL, &IID_Recordset15, (void **)&pRst);
if (hr)
MessageBox(0, TEXT("Error CoCreateInstance()"), 0, 0);
else
{
VARIANT v1, v2;
VariantInit(&v1);
v1.vt = VT_BSTR;
v1.bstrVal = SysAllocString(L"SELECT * FROM test");
VariantInit(&v2);
v2.vt = VT_BSTR;
v2.bstrVal = SysAllocString(L"Driver={Microsoft Access Driver (*.mdb)};Dbq=test.mdb;");
// STDMETHOD(Open)(THIS,VARIANT,VARIANT,enum CursorTypeEnum,enum LockTypeEnum,LONG);
hr = pRst->lpVtbl->Open(pRst, v1, v2, adOpenKeyset, adLockUnspecified, adCmdText);
SysFreeString(v1.bstrVal);
SysFreeString(v2.bstrVal);
//hr = pRst->lpVtbl->Open(pRst, v1, v2, 1, -1, -1);
if (!hr) {
Fields* pFlds;
Field* pFld;
long nRecs = 0;
hr = pRst->lpVtbl->get_RecordCount(pRst, &nRecs);
_tprintf(TEXT("nRecs = %d\n"), nRecs);
hr = pRst->lpVtbl->get_Fields(pRst, &pFlds);
if (!hr) {
long nFlds;
VARIANT vIdx;
hr = pFlds->lpVtbl->get_Count(pFlds, &nFlds);
_tprintf(TEXT("nFlds = %d\n"), nFlds);
VariantInit(&vIdx);
vIdx.vt = VT_I4;
for (int i = 0; i < nFlds; i++) {
vIdx.lVal = i;
hr = pFlds->lpVtbl->get_Item(pFlds, vIdx, &pFld);
if (!hr) {
BSTR bstrTmp;
VARIANT v3;
VariantInit(&v3);
v3.vt = VT_BSTR;
v3.bstrVal = bstrTmp;
hr = pFld->lpVtbl->get_Name(pFld, &bstrTmp);
if (!hr) {
_tprintf(bstrTmp);
SysFreeString(bstrTmp);
}
hr = pFld->lpVtbl->get_Value(pFld, &v3);
if (!hr) {
if (v3.vt == VT_BSTR) {
_tprintf(TEXT(" %ls\n"), bstrTmp);
SysFreeString(bstrTmp);
} else {
VariantChangeType(&v3, &v3, VARIANT_LOCALBOOL, VT_BSTR);
_tprintf(TEXT(" %ls\n"), bstrTmp);
SysFreeString(bstrTmp);
}
}
pFld->lpVtbl->Release(pFld);
}
}
pFlds->lpVtbl->Release(pFlds);
}
} else
_tprintf(TEXT("%Xh %ls\n"), hr, GetADOErrorCode(hr));
pRst->lpVtbl->Release(pRst);
}
CoUninitialize();

//MessageBox(0, TEXT("Done"), 0, 0);
return 0;
}
--- End code ---
Let me know, if there is something wrong.

czerny:
If the database doesn't exist, I get: 80004005h Unspecified Error
Shouldn't be used in this case:  800A0F0Bh Database does not exist?

TimoVJL:
A simple ADO test, not useful
Those who have MS Office or AccessDatabaseEngine installed can test it with test.mdb

jj2007:
Looks good, Timo, and works fine, but how do you get the names of tables after OpenSchema? I tried this:


--- Code: --- hr = pCon->lpVtbl->OpenSchema(pCon, adSchemaTables, vtCriteria, vtMissing, &pRst);
if (!hr) {
printf("Recordset tables=%i\n", pRst);
printf("Count=%i\n", pRst->GetRows);
pRst->lpVtbl->Release(pRst); // release the _Recordset
printf("Recordset close\n");
--- End code ---

Unknown field 'GetRows' of '_Recordset (aka struct _Recordset)'
 :(

TimoVJL:
something like this:

--- Code: --- hr = pCon->lpVtbl->OpenSchema(pCon, adSchemaTables, vtCriteria, vtMissing, &pRst);
if (!hr) {
Fields* pFlds;
Field* pFld;
long nRecs = 0;
hr = pRst->lpVtbl->get_RecordCount(pRst, &nRecs);
printf("nRecs = %d\n", nRecs);
hr = pRst->lpVtbl->get_Fields(pRst, &pFlds);
if (!hr) {
long nFlds = 0;
hr = pFlds->lpVtbl->get_Count(pFlds, &nFlds);
printf("nFlds = %d\n", nFlds);
VARIANT vIdx;
VariantInit(&vIdx);
vIdx.vt = VT_I4;
for (int i = 0; i < nFlds; i++) {
vIdx.lVal = i;
hr = pFlds->lpVtbl->get_Item(pFlds, vIdx, &pFld);
if (!hr) {
BSTR bstrTmp;
VARIANT v3;
VariantInit(&v3);
v3.vt = VT_BSTR;
v3.bstrVal = bstrTmp;
hr = pFld->lpVtbl->get_Name(pFld, &bstrTmp);
if (!hr) {
printf("%ls\n", bstrTmp);
SysFreeString(bstrTmp);
}
}
pFld->lpVtbl->Release(pFld);
}
pFlds->lpVtbl->Release(pFlds);
}
// done
pRst->lpVtbl->Release(pRst);
printf("Recordset close\n");
}
--- End code ---

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