可使用SafeArrayPtrOfIndex，我以前写的一段代码，参考看看，

var
pFields, pRows: PSafeArray;
ArgIndices: array[0..1] of Integer;
Argsabound: array[0..0] of TSafeArrayBound;
vFields, vRows: OleVariant;
PtrOfIndex: Pointer;
I, iPer, iRecordCount: Integer;
begin
。。。
Argsabound[0].lLbound := 0;
Argsabound[0].cElements := 1;
pFields := SafeArrayCreate(VT_VARIANT, 1, Argsabound);
ArgIndices[0] := 0;
ArgIndices[1] := 0;
{

//多线程环境下使用
SafeArrayLock(pFields);
try
SafeArrayPtrOfIndex(pFields, (@ArgIndices)^, PtrOfIndex);
finally
SafeArrayUnLock(pFields);
end;
}
SafeArrayPtrOfIndex(pFields, (@ArgIndices)^, PtrOfIndex);
POleVariant(PtrOfIndex)^ := AFieldName;

。。。