C / C++ / MFC

CPallini wrote:

What about _variant_t containing arrays?

_variant_t v;
// Assign a SAFEARRAY value to v
CComSafeArray<char, VT_UI1> sa(V_ARRAY(&v));
// Now we can access the SAFEARRAY using sa.

_variant_t v;
// Set a value in v
CString s = v;

_variant_t vtValue;
vtValue = m_pRset->Fields->GetItem("Bianry")->GetValue();
CString b=vtValue;
output is b = "??4"
when i copy the vtValues at the time of debug then i got values 
safearray of UI1 = [20](54 '6',53 '5',52 '4',54 '6',52 '4',0,0,0,0,0,0,0,0,0,0,0,0,0,0,0)

CComSafeArray<char, VT_UI1> sa(V_ARRAY(&v));
CString s;
for(int index=sa.GetLowerBound();index<=sa.GetUpperBound()&&sa[index];++index)
{
   s+=sa[index];
}

BSTR b;
BstrFromVector(pSA,&b);
CStringA s = (LPCSTR)b;

_variant_t v;
v = 3.141;
::VariantChangeType(&v, &v, 0, VT_BSTR);
CString s = (LPTSTR)(_bstr_t)v.bstrVal;

Vetukuri Raju wrote:

And i have also tried to giv the library paths through #pragma comment(lib,"...")

UKM_Student wrote:

he part where i bold-ed, why is there a need to put in the sign '...'?

UKM_Student wrote:

I tried running it without the '...' sign but the program won't run. It says its undeclared.

UKM_Student wrote:

2)From (1),whats the difference if i put ".." instead of '...'?

UKM_Student wrote:

3)If i were to declare something of type int,say "count=1".Why will the program run with count=1 and NOT run if i put count='1'.(see (4)where i put a '...' sign before and after the 0/26 after count)

UKM_Student wrote:

4)If i were to modify my program into the following :


#include<iostream>
using namespace std;
int main()
{
char letter='A',count='0';

while(count<='26')
{
cout<<letter;
letter++;
count++;
}

return 0;
}<="" blockquote="">

Typing nearly random statements inside the IDE maybe amusing, I guess...


I strongly suggest you read a good C/C++ tutorial.

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

UKM_Student wrote:

What do u mean by IDE?

UKM_Student wrote:

And regarding part 3, when i put count='1',the whole compiler runs it and gets stuck O_O,need to restart :X

UKM_Student wrote:

The program i wrote...

UKM_Student wrote:

1) The part where i bold-ed, why is there a need to put in the sign '...'?

UKM_Student wrote:

What do u mean by really?

I remembered asking that question before and someone helped me out in editing my "wrong" program...

UKM_Student wrote:

i forgot to ask why he needed to put that '...' sign,

UKM_Student wrote:

...through trial and error i managed to produce the following :

#include<iostream>
#include<string>
using namespace std;
int main()
{
char letter='A',count=1;

while(count<=26)
{
cout<<letter;
letter++;
count++;
}
return 0;
}<="" blockquote="">

What trial and error? The code I gave you worked fine. Why the introduction of count?

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