Re: How to deal with reference variable in C#? - C# Discussion Boards

How to deal with reference variable in C#?

Ron.S3-Jun-07 19:55

3-Jun-07 19:55

Hello,

I have created a DLL for COM using VB 6.0. the fucntion has a reference variable which returns some value back.
I am accessing this fuction in C# when i am passing the ref variable it is giving me an error.
Please help.

Thanks in Advance.

Bharath.S Ron

Re: How to deal with reference variable in C#?

Sathesh Sakthivel3-Jun-07 20:20

Sathesh Sakthivel

3-Jun-07 20:20

bharath.s.r wrote:
I am accessing this fuction in C# when i am passing the ref variable it is giving me an error.

What error?

Regards,

Satips. Rose | [Rose]

Re: How to deal with reference variable in C#?

Ron.S3-Jun-07 20:33

Ron.S

3-Jun-07 20:33

i am passing a variable as (ref var)
error :- ref object is not declared.

Thanks in Advance.

Bharath.S Ron

Re: How to deal with reference variable in C#?

KKrista3-Jun-07 20:47

KKrista

3-Jun-07 20:47

Reference variables are surely supported in C#.

I think the problem under this case might be the use of variable without declaration.

Regards,
Murali

Re: How to deal with reference variable in C#?

Ron.S3-Jun-07 20:57

Ron.S

3-Jun-07 20:57

can u please explain me how i have to rectify it.

i Have learn't C# on my own, i was working on VB Before now has been shifted to C#.
Thanks in Advance.

bharath.s

Re: How to deal with reference variable in C#?

KKrista3-Jun-07 21:07

KKrista

3-Jun-07 21:07

While calling the method, pass the 'reference' variables as

SomeMethod(ref varInput);

Then in the definition of the Method u have to use the same reference variable as,

public void SomeMethod(ref varInput)
{
//Give ur implementation here.
}

Regards,
Murali

Re: How to deal with reference variable in C#?

Ron.S3-Jun-07 21:15

Ron.S

3-Jun-07 21:15

the method has allready being deployed in vb6.o

in vb 6.0:-
public function somefunc(ref variable as string)
variable = "XYZ"
end function
in C# i have given reference to this class and function and created a Runtime callable wrapper.

IN c#

object.somefunc(ref csharpvar)

bharath.s

Re: How to deal with reference variable in C#?

jayart4-Jun-07 5:53

jayart

4-Jun-07 5:53

Make sure you are using the correct namespace.

Re: How to deal with reference variable in C#?

jimpalmer4-Jun-07 8:08

jimpalmer

4-Jun-07 8:08

maybe this?

IN c#

string csharpvar; //var must be declared first
object.somefunc(ref csharpvar)

Getting The Difference Between Months

zoroyster3-Jun-07 19:12

zoroyster

3-Jun-07 19:12

Hi, Im trying to create a C# program that will compute the exact number of months between two durations.

This is my code

TimeSpan duration = startTime - stopTime;

//to compute the difference between days, I use this code

int result = (duration.Days);

unfortunately it stops with duration.Days.. there are no available methods that will compute the months or years (eg. duration.Months , duration.Years)

i tried to compute the days and divide it by 30, but this approach is highly innacurate.

Hope you guys can help

tnx

Re: Getting The Difference Between Months

Harini N K3-Jun-07 19:25

Harini N K

3-Jun-07 19:25

Hi
Check this link

http://www.c-sharpcorner.com/UploadFile/DipalChoksi/DateDiff_CS_DC09132006172429PM/DateDiff_CS_DC.aspx[^]

Harini

Re: Getting The Difference Between Months

zoroyster3-Jun-07 21:30

zoroyster

3-Jun-07 21:30

Hi harini. Thanks for the reply. Ive read the link, but it doesn't mention anything about getting the difference between two dates in months :c

Hope you have other references..

tnx!

Getting Tasks

M. J. Jaya Chitra3-Jun-07 19:02

M. J. Jaya Chitra

3-Jun-07 19:02

Hai! everybody,
I want to get all the running tasks in my windows os.
Plz give me an hint

Best Regards,
M. J. Jaya Chitra

Re: Getting Tasks

mav.northwind3-Jun-07 19:10

mav.northwind

3-Jun-07 19:10

Hi!
You can use the Process class.

Regards,
mav

--
Black holes are the places where God divided by 0...

Re: Getting Tasks

deepan600403-Jun-07 19:10

deepan60040

3-Jun-07 19:10

Directly u see the Task manager.. or in a .net frame work means Process option is there la.. Its wright take it or u got correct ans intimate me..

Regards..
Maldeeban.R

Hi i am working as a software engineer.. this code project site articles is very usefull for us.. I am very interst to read this articales..

Re: Getting Tasks

M. J. Jaya Chitra3-Jun-07 19:21

M. J. Jaya Chitra

3-Jun-07 19:21

It is giving the process name i.e Winword but i want to display the tasks as in task manager and i would like to start or stop the tasks even though it is running in the client machine
I tried the Service Controller class also it is giving only the windows services

Best Regards,
M. J. Jaya Chitra

Run time callable wrapper?

Ron.S3-Jun-07 18:29

Ron.S

3-Jun-07 18:29

Hello Friends ,

I have a situation here , i have a com component (DLL) which is created in VB , i am accessing the dll in C#.Net .
The problem here is i have parameters to which are optional, but in c# while accessing it is giving me message saying that parameter is mandatory.
Example:-

vb6.0
Public function operation(byval a as integer,byval b as integer, optional symbol as string)
dim output as integer
case symbol

when "+"
output = a+b
when "-"
output = a-b
end case

endfunctin

i am calling this function in C#.

Here the symbol is optional . how i have to hadle the situation?

Thanks in advance.

Bharath.S.Ron

Re: Run time callable wrapper?

mav.northwind3-Jun-07 19:11

mav.northwind

3-Jun-07 19:11

Hello!
In this case you'll have to use Type.Missing for the optional parameters you don't want to fill in.

Regards,
mav

--
Black holes are the places where God divided by 0...

Any difference between returning an object and changing an object passed into a static function? [modified]

xdavidx3-Jun-07 16:47

xdavidx

3-Jun-07 16:47

I was wondering if there was any difference between the following code:

<br />
public void LoadAll()<br />
{<br />
obj x;<br />
    //static function that will change the object<br />
    StaticClass.DoSomething(x);<br />
}<br />

<br />
public void LoadAll()<br />
{<br />
    //static function that will return a new object<br />
    obj x = StaticClass.DoSomething();<br />
}<br />

Are there any pros and cons to either of these? Are there any concerns with thread safety?

-- modified at 22:55 Sunday 3rd June, 2007

Re: Any difference between returning an object and changing an object passed into a static function?

Christian Graus3-Jun-07 17:09

Christian Graus

3-Jun-07 17:09

Any concerns you may have remain the same in either case, ultimately I'd go with the second for clarity, but so long as it's all running in the same thread, which it is here, I don't see any thread safety concerns. The second approach does allow the method to create the object whenever it likes, the first means it always exists.

The first would be better represented with the out keyword, seeing as you expect the value to be assigned, and not just read. Stupid C# doesn't have const, but you can make your code clear by using the out keyword.

Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )

charecter input system function

sonavi3-Jun-07 14:48

sonavi

3-Jun-07 14:48

i want the reference for the charecter input system function code which is simmilar to windows operating system.

Please provide me the reference

Help Ever Hurt Never

Re: charecter input system function

Christian Graus3-Jun-07 14:59

Christian Graus

3-Jun-07 14:59

You've asked this several times now. Surely you realise that anyone who knows what the windows code is, probably isn't allowed to show it to you ?

Even if I had the Windows source, and was able to share it, I would honestly have no idea what part of it you want to know about, based on how you word your question. You want to know how the textbox works ? How the keyboard is monitored ? How the console shows key preses ? I have no idea.

Save PDF file as image

There is always the way to do it, but I don't know3-Jun-07 14:22

There is always the way to do it, but I don't know

3-Jun-07 14:22

What is the best way to save currently opened PDF file as image in sql database?

Re: Save PDF file as image

xibeifeijian3-Jun-07 14:35

xibeifeijian

3-Jun-07 14:35

Look the TEXTPTR function in SQLServer's help.You may find the answer.