CRecordSet

[starmoon]

i want to receive the data use the recordset
exec like "select * from student where ages=23"
where i can put the m_nParam,m_strFilter,the Rfx(..) and so so,
the best is sample,

[Sniper]

what is your problem? 说中文是不是清楚一点？

[oo]

pSet->m_strFilter = "ages = 23";
pSet->Requery();
(pSet：pointer of your recordset)
这样应该就可以了。

[sintony]

CDaoDatabase m_database; //CDaoRecordset和CRecordset原理上是一样的
CDaoRecordset* m_pRecordset;

CStringArray m_arrayFieldName;
CWordArray m_arrayFieldSize;

m_strConnect = "ODBC;";
m_database.Open("Odbc名", FALSE, TRUE, m_strConnect);

m_strQuery.Format("select * from [%s]","student" ); //select * from student where ages=23
m_pRecordset = new CDaoRecordset(&m_database);
m_pRecordset->Open(dbOpenDynaset, m_strQuery, dbReadOnly);

m_nFields = (int) m_pRecordset->GetFieldCount();
m_arrayFieldName.SetSize(m_nFields);
m_arrayFieldSize.SetSize(m_nFields);
CDaoFieldInfo fi;
for(int i = 0; i < m_nFields; i++) {
m_pRecordset->GetFieldInfo(i, fi);
m_arrayFieldName[i] = fi.m_strName;
m_arrayFieldSize[i] = (short) max(min(fi.m_lSize, 50),fi.m_strName.GetLength());
TRACE("field name = %s\n", fi.m_strName);
}

当然如果你的数据库格式不需要通用的话，最简单的方法使用vc的New Class继承CRecordset选择数据库，这样他会自动建立和数据的联系
通过member variables。

[sintony]

for (int i = 0; i < pDoc->m_nFields; i++) {
var = m_pSet->GetFieldValue(i);
switch (var.vt) {
case VT_BSTR:
str = (LPCSTR) var.bstrVal; // narrow characters in DAO
break;
case VT_I2:
str.Format("%d", (int) var.iVal);
break;
case VT_I4:
str.Format("%d", var.lVal);
break;
case VT_R4:
str.Format("%10.2f", (double) var.fltVal);
break;
case VT_R8:
str.Format("%10.2f", var.dblVal);
break;
case VT_CY:
str = COleCurrency(var).Format();
break;
case VT_DATE:
str = COleDateTime(var).Format();
break;
case VT_BOOL:
str = (var.boolVal == 0) ? "FALSE" : "TRUE";
break;
case VT_NULL:
str = "----";
break;
default:
str.Format("Unk type %d\n", var.vt);
TRACE("Unknown type %d\n", var.vt);
}
pDC->TextOut(x, y, str);
x += pDoc->m_arrayFieldSize[i] * m_nCharWidth;
}

[dengdun]

先定义一个你自己的CRecordSet类的实例rs，然后调用
rs.m_strFilter=...;
rs.m_m_nParam=...;
最后，在rs.Open()或rs.Requery();

[starmoon]

thanks a lot,
the realy problem is
i derieved a class like CStudent from CRecordset use the class wizard.
i want to exec the sql like "select * from the student where ages = certenage",i want to throh modify the member verible or member function of CStudent ,how and where can i do this .not in the program.

[oo]

you can add a member function do that.