Hi all.,
I got some info from this iink
where u can find.,

Public Class LibWrap
' Visual Basic does not support varargs, so all arguments must be
' explicitly defined. CallingConvention.Cdecl must be used since the stack
' is cleaned up by the caller.
' int printf( const char *format [, argument]... )
<DllImport("msvcrt.dll", CallingConvention := CallingConvention.Cdecl)> _
Overloads Shared Function printf ( _
format As String, i As Integer, d As Double) As Integer
End Function
<DllImport("msvcrt.dll", CallingConvention := CallingConvention.Cdecl)> _
Overloads Shared Function printf ( _
format As String, i As Integer, s As String) As Integer
End Function
End Class 'LibWrap
Public Class App
Public Shared Sub Main()
LibWrap.printf(ControlChars.CrLf + "Print params: %i %f", 99,
99.99)
LibWrap.printf(ControlChars.CrLf + "Print params: %i %s", 99, _
"abcd")
End Sub 'Main
End Class 'App

if VB.NET does't support VarArgs then how come
Console.Write("Test{0}{1}..",3,4) is works?


Regards Balamurali C

"Balamurali C" <(E-Mail Removed)> wrote in message
news230CCD2-5282-494F-9DF4-(E-Mail Removed)...
> if VB.NET does't support VarArgs then how come
> Console.Write("Test{0}{1}..",3,4) is works?

There are lots of overloads of Write: one takes one object, another takes
two and another three (other than the format string). Take a look at an
example of this call in ILDASM, C# and VB.NET call this method:

call void [mscorlib]System.Console::Write(string, object, object)

now try this:

Console.Write("Test{0}{1}{2}{3}",3,4,5,6)

If you look at ILDASM you'll see that the following method is called:

call void [mscorlib]System.Console::Write(string, object[])

The compile creates an array of the parameters to Write before calling the
method.

If you try to call this same line in managed C++ you'll see that it calls:

call vararg void [mscorlib]System.Console::Write(string, object, object,
object, object)

In other words, only C++ calls vararg methods, and C++ can only call them,
it cannot write them. To write a vararg method you have to use ILASM.

Richard
--
My email address (E-Mail Removed) is encrypted with ROT13 (see
www.rot13.com)

hi Richard Grimes
Ya thanks for your reply. still i hve some queries.,
I asked some c# people they said we can use Param (nearly equl to this name) Object to get number of parameter & paramter values too.
this is conflicts me.,


and one more thing., is it good way or writting overload function code which take 1 to n paramter, where n is big number.

like
write(string,object);
write(string,object,object);
............
...........
write(string,object,object................);


"Richard Grimes [MVP]" wrote:

> "Balamurali C" <(E-Mail Removed)> wrote in message
> news230CCD2-5282-494F-9DF4-(E-Mail Removed)...
> > if VB.NET does't support VarArgs then how come
> > Console.Write("Test{0}{1}..",3,4) is works?
>
> There are lots of overloads of Write: one takes one object, another takes
> two and another three (other than the format string). Take a look at an
> example of this call in ILDASM, C# and VB.NET call this method:
>
> call void [mscorlib]System.Console::Write(string, object, object)
>
> now try this:
>
> Console.Write("Test{0}{1}{2}{3}",3,4,5,6)
>
> If you look at ILDASM you'll see that the following method is called:
>
> call void [mscorlib]System.Console::Write(string, object[])
>
> The compile creates an array of the parameters to Write before calling the
> method.
>
> If you try to call this same line in managed C++ you'll see that it calls:
>
> call vararg void [mscorlib]System.Console::Write(string, object, object,
> object, object)
>
> In other words, only C++ calls vararg methods, and C++ can only call them,
> it cannot write them. To write a vararg method you have to use ILASM.
>
> Richard
> --
> My email address (E-Mail Removed) is encrypted with ROT13 (see
> www.rot13.com)
>
>
>
>

> Ya thanks for your reply. still i hve some queries.,
> I asked some c# people they said we can use Param (nearly equl to this
name) Object to get number of parameter & paramter values too.
> this is conflicts me.,

Sorry, I wasn't clear in the reply. The version of Write that has an array
of objects is the one that uses the params keyword. The C# params keyword
has *nothing* to do with varargs, all it means is that there follows an
array of parameters and the method has the responsibility of reading the
parameters out of the array.

> and one more thing., is it good way or writting overload function code
which take 1 to n paramter, where n is big number.
>
> like
> write(string,object);
> write(string,object,object);
> ...........
> ..........
> write(string,object,object................);

Why not? You can write a single method that takes n parameters, and then the
other methods take 1 to n-1 parameters and just call the n parameter version
passing null in appropriate parameters. The methods with 1 to n-1 parameters
are just there for convenience and its a design decision as to which ones
are useful.

Richard
--
My email address (E-Mail Removed) is encrypted with ROT13 (see
www.rot13.com)

Hi Richard Grimes very thx for ur reply.,
What might be the n value., as per microsoft definision.,

bcoz., supposing that can I give
let n = 1000
Console.write("{0}{1}..{n} ",1,2............n);

regards
Balamurali c


"Richard Grimes [MVP]" wrote:

> > Ya thanks for your reply. still i hve some queries.,
> > I asked some c# people they said we can use Param (nearly equl to this
> name) Object to get number of parameter & paramter values too.
> > this is conflicts me.,
>
> Sorry, I wasn't clear in the reply. The version of Write that has an array
> of objects is the one that uses the params keyword. The C# params keyword
> has *nothing* to do with varargs, all it means is that there follows an
> array of parameters and the method has the responsibility of reading the
> parameters out of the array.
>
> > and one more thing., is it good way or writting overload function code
> which take 1 to n paramter, where n is big number.
> >
> > like
> > write(string,object);
> > write(string,object,object);
> > ...........
> > ..........
> > write(string,object,object................);
>
> Why not? You can write a single method that takes n parameters, and then the
> other methods take 1 to n-1 parameters and just call the n parameter version
> passing null in appropriate parameters. The methods with 1 to n-1 parameters
> are just there for convenience and its a design decision as to which ones
> are useful.
>
> Richard
> --
> My email address (E-Mail Removed) is encrypted with ROT13 (see
> www.rot13.com)
>
>
>