C# Discussion Boards - CodeProject

Re: A problem occurs while connecting(using Socket Class)

19-Aug-09 1:17

Ya budy i tried it more than once .... it gives me a reply from the command prompt but it is still an error in VS .......

stancrm19-Aug-09 1:28

Re: A problem occurs while connecting(using Socket Class)

19-Aug-09 1:28

If you still having problem with connection, check the firewall, most problems are firewall thing.

stancrm19-Aug-09 1:34

Re: A problem occurs while connecting(using Socket Class)

19-Aug-09 1:34

Just for example :
It's working for me. No exception.

TcpClient tcpClient = new TcpClient();
tcpClient.Connect("213.55.66.247", 80);

NetworkStream networkStream = tcpClient.GetStream();

byte[] buffer = Encoding.ASCII.GetBytes("Hello World");
networkStream.Write(buffer, 0, buffer.Length);

networkStream.Close();
tcpClient.Close();

CoderForEver19-Aug-09 1:37

Re: A problem occurs while connecting(using Socket Class)

19-Aug-09 1:37

Are you working on a client/server based? ....... By the way I checked the fire wall ..... still a problem..

CoderForEver19-Aug-09 1:40

Re: A problem occurs while connecting(using Socket Class)

19-Aug-09 1:40

Hey budy .... What you works for u didnt work for me .... I think the problem might be with ma pc....
So can you tell me how to check wheter the port is opened or not?? .... or any other means ..

Thank you

stancrm19-Aug-09 1:44

Re: A problem occurs while connecting(using Socket Class)

19-Aug-09 1:44

Yea, that means your PC is blocking your application. Or the target PC is blocking your PC.. Smile | :)

That's not .NET problem, that is the problem of your windows / firewall.
Using that code, I have tried to connect to that IP with port 80, it's working for me.

CoderForEver19-Aug-09 1:50

Re: A problem occurs while connecting(using Socket Class)

19-Aug-09 1:50

So how am i goin to check wheter the port is opened or not? Because I turrned off the Firewall .. I think the problem may be on the port........... By the way can I send a connection to the pc I am working on(the same pc where the application runs)?

stancrm19-Aug-09 2:00

Set SelectedValue of ComboBox

19-Aug-09 2:00

If you can connect to it, that means port 80 is opened.
If you cannot connect to it, that means target is not available or your IP has been blocked from target PC.

DIPAK@EMSYS19-Aug-09 0:22

DIPAK@EMSYS

19-Aug-09 0:22

Hi All,
I have combobox with name cmbClassId.
I have to set the SelectedValue for this combo with the value form the DataTable Cell value.

I have done it like below.

cmbClassId.SelectedValue = (object)dataSet.Tables[Constants.STUDENT].Rows[0]["StudentClassId"];

but still it is showing me null in SelectedValue property of this combo...

please help me out...

Thanks & Regards
Dipak Thesiya

dipak

Re: Set SelectedValue of ComboBox [modified]

Hristo-Bojilov19-Aug-09 0:31

Hristo-Bojilov

19-Aug-09 0:31

Try with SelectedItem property.It seem's that the property doesn't works fine ^.

Life is a stage and we are all actors!

modified on Wednesday, August 19, 2009 6:47 AM

Re: Set SelectedValue of ComboBox

DIPAK@EMSYS19-Aug-09 0:36

DIPAK@EMSYS

19-Aug-09 0:36

i am supposed work with SelectedValue Property....

dipak

Re: Set SelectedValue of ComboBox

Calla19-Aug-09 2:05

Calla

19-Aug-09 2:05

Did you remember to set the ValueMember of the ComboBox?

[Message Deleted]

Nitin K19-Aug-09 0:10

Nitin K

19-Aug-09 0:10

[Message Deleted]

Re: how to change

CoderForEver19-Aug-09 0:23

USB + Restricted file access

19-Aug-09 0:23

First change the SUBJECT TITLE then peoples may answer your question.

Azghar Hussain18-Aug-09 23:27

18-Aug-09 23:27

Hi,

We have some import data files which we will release along with our software which we don't want any of our client to access it , copy it, cut it, read it, etc...

After searching in google, I am getting an impression that we can keep our important data in USB. This USB we will given to user along with the application. Application should be able to access the contents of USB, but our client should not be able to see anything in USB or atleast could open it.

Is it possible... How to achieve this through coding...

alternatively I also thought an idea of encrypting and decrypting the file... there are two issues with it..
a) Encrpting and decrypting will take more time..
b) There are chances that user may able to compy decrpyted files.

Thanks in advance

If you have faith in the cause and
the means and in God, the hot
Sun will be cool for you.

stancrm18-Aug-09 23:50

18-Aug-09 23:50

I think, if you want something like that, you must encrypt the data in it. If you open the data using windows explorer -> it is encrypted. And in your application, you must decrypt the data to see it.

Azghar Hussain18-Aug-09 23:54

Re: USB + Restricted file access [modified]

18-Aug-09 23:54

I can't do that because data is very huge... decrypting is going to take nearly 10 min... User waiting for 10 min to launch an application is not a good idea.

If you have faith in the cause and
the means and in God, the hot
Sun will be cool for you.

annathor19-Aug-09 0:20

annathor

19-Aug-09 0:20

maybe create your own propertiary binary fileformat to store the data in, obfuscate the data in the binary file, throw in som red herrings.
If you have time and resources, maybe create your own file system format (Maybe take a look at the FUSE API?), that windows isn't able to read from, and format the usb sticks to that format, have an implementation of a "yourWackyFS"-reader in your app, this probably means that you need to write a dll to access the files on your filesystem in ASM (to get the low level Red/write access you need), or a dll writen in c/c++ whit alot of inline ASM and p/invoke the dll into your C# application WTF | :WTF:

.

Maybe encrypt the important data in the file, and not the whole file, and decypt only the data you need when you need it?

An another posibilty is at setup of your application, create a virtuel disk on the users computer, that is not visible for the user and only accessable by the proper processes, and save the file to that virtual disk. (Maybe take a look at this product: http://www.eldos.com/solfs)

modified on Wednesday, August 19, 2009 6:52 AM

Azghar Hussain19-Aug-09 2:45

Re: USB + Restricted file access [modified]

19-Aug-09 2:45

Case is we have ArcGIS shape and grid file... We are using map window OCX control to load and show the shape file... OCX controls wants the physical file path of the shape file to open it... I cannot change the format of the file because it is ESRI standard format... We want to protect these shape files from being copied, getting deleted...

Creating virtual disk is not possible in C#

If you have faith in the cause and
the means and in God, the hot
Sun will be cool for you.

annathor19-Aug-09 3:30

annathor

19-Aug-09 3:30

Isn't ArcGIS shape just a renamed zip-file containing a dbase database and some text files with meta data?
maybe it is posible to create your own format, and recreate the zip/shape file in-memory using sharpziplib and stream the in-memory shape file to the OCX control? and then you can encrypt key data in the binary file.

"Creating virtual disk is not possible in C#" - yes it is, it's just a matther of what dll's you p/invoke, and ...huhum...
C:\Program Files\EldoS\SolFS\dotNET\Managed, or if eldos isn't your thing, maybe This is?

modified on Wednesday, August 19, 2009 9:52 AM

Azghar Hussain19-Aug-09 6:59

19-Aug-09 6:59

thanks for reply...
I am using map window ocx control whose API requires fullpath of shape file to passed as paramter to be loaded.. I can't pass stream to it.

Can you help me by giving the link of source code about how to create virtual drive in C#

Is there any alternate way to handle it....

thanks again

If you have faith in the cause and
the means and in God, the hot
Sun will be cool for you.

Embed and manipulate Excel sheet

annathor20-Aug-09 2:00

annathor

20-Aug-09 2:00

Here is what you are looking for Eterlogic virtual Drive SDK

Quote:
"Virtual Drive SDK allows you to create and manage virtual disks that appear in Windows as regular disks. Virtual disk can be located anywhere: on hard disk, network, random access memory, database etc. To do this on your own you need to develop a driver that requires deep knowledge of operating system internals, and a lot of time for debugging and testing it. Virtual Drive SDK makes possible to implement read/write operations without having to develop your own kernel driver. All necessary part of boring work is done, so you can focus on storage, encryption etc. "

Quote:
" * Simultaneous work with up to 8 virtual disks
* Simple user mode API for kernel driver management
* User application freeze/crash detection
* Automatic removal of dead volumes
* Read-only volumes support
* Built-in formatting support
* Samples for C++, C#, Delphi, Python
* Special distribution mode (does not require separate SDK installation)"

The_Collector18-Aug-09 23:17

The_Collector

18-Aug-09 23:17

Hello everyone.

I'm googling a lot of sites but none gives me a near answer to my requirements.

I'm am about to work on a project which requires me to use excel sheet to handle the inputs and computation... and later all values inputed and computed will be stored in a database....
below are the steps...

1. store or embed an excel file as one(1) record in a database. Every record has different computations and inputs... in short, embeded excel sheet will serve as templates for future data entry

2. Data entry proper.
      a. embeded excel sheet will display only the columns "A and B".
               hidding the rest of colums which has the formulas in it.
      b. upon losing the focus, columns "A and B" will be computed
               based on the formulas from the hidden columns.
      c. Save the updated template in another table as new record.
      d. Read the inputed and computed values from embeded excel,
               then store it in a table as new record.

Hope some can guide or can give me a sample of the above requirement... Thank you in advance...

xxx

Re: Embed and manipulate Excel sheet

stancrm18-Aug-09 23:52