C# Discussion Boards - CodeProject

Jeff J16-Dec-02 19:26

16-Dec-02 19:26

I've done the sort of thing you're looking to do. In the Win32 API, you start with FindFirstFileEx(), FindNextFile(), and finally FindClose(), while walking the desired directory tree. That is exactly how the find/search applet in Windows does it, and it's very fast.

Once you have the desired file [by extension], just open it and search it. If the file is not too large, I recommend loading an entire buffer with the contents, then searching the whole thing. If the file is big, it's a little more complicated, because the beginning of the string to be found might lie at the end of one buffer full, and the end of it at the start of the next buffer full. Thus, you need to "overlap" the buffers, if you will, for at least the length of the string to search for. I did this with cyclic buffers, but there's no need to get fancy.

The CLR already wraps those Find* functions in the Directory class, with methods like GetFileSystemEntries() - the closest equivalent - and GetFiles(). Opening and searching the files is pretty much the same in .Net as in the Win32 API.

Cheers

ListView Icon Selection

Jonathan Austin16-Dec-02 11:04

Jonathan Austin

16-Dec-02 11:04

Hello,

I have a ListView that is set in Details mode for the view. It has no headers though that's likely irrevalent. I have a SmallImageList set and I set an icon for a ListViewItem. When an Item is selected, it also highlights the icon on the left. How would I stop it from highlighting it? I know that I could catch the WM_PAINT but then would I have to repaint the whole control? Is there something that I'm missing?

Thanks,
Jonathan

Re: ListView Icon Selection

Jonathan Austin16-Dec-02 11:21

Jonathan Austin

16-Dec-02 11:21

Ok. This was a bad question. The standard ListView does not highlight the icon. I am trying to modify the TreeListView that was posted on CodeProject and it does highlight the icon using a ListView. I will have to investigate more.

Re: ListView Icon Selection (I butchered it)

Jonathan Austin16-Dec-02 12:25

Jonathan Austin

16-Dec-02 12:25

It appears that I butchered my question. I still have the original question. When I went back and look at my other example, the icon I was looking at just didn't show the highlight as bad. Therefore, does anyone know the answer to my question?

Thanks,
Jonathan

Re: ListView Icon Selection (I butchered it)

Jeff J16-Dec-02 19:03

Jeff J

16-Dec-02 19:03

Highliting the icon is handled automatically by listviews, and there is no style bit or anything to override that behaviour. I also wish only the text were highlited, but to do so would mean custom drawing, as you mentioned. I have done it, but that code is somewhere in the archives of a company I once worked for.

If you still desire to do so, the drawing of the foreground and background colors is fairly easy, but handling the drawing of the focus rectangle is a bit of a pain (at least when multi-select is enabled). Be careful when drawing selection ranges, as you need to remember which item is the "pivotal" selection (I forget the official term, it's been a while). Othewise, you won't be able to extend or reverse selection changes properly, when the user keeps CTRL or SHIFT down.

Re: ListView Icon Selection (I butchered it)

Jonathan Austin17-Dec-02 8:08

Jonathan Austin

17-Dec-02 8:08

Thank you for your response.

I have been looking at some of Carols Perez's great work here on CodeProject where he does a lot of customdraw listviews and treeviews. It gets pretty complicated as you have to receive all of the correct messages and such. It looks like I'm going to just let it go for now and I may change it a little later. Custom control Drawing does not appear to be one of my strong points. Smile | :)

Jonathan

question on string and encryption sorta

jtmtv1816-Dec-02 9:51

jtmtv18

16-Dec-02 9:51

can any help me with a problem ! ... i have a encryption program that encrypts (anything) in RC2 or DES. the encryption method is in a static void and gets the (readfile) (writefile) (password)

the read file comes in the form of a full path name ie(c:\something\test.exe) then it is sent to the (readfile) part of encryption as a string. my question is how can i try this directory name and just show the file name(test.exe) and send that too (writefile) with a *.enc extention on it but still preserving the original write name. !! i have not clue how to do this. all i really need to do is trim the string but how because what if the directory isnt the exsact same size as (c:\something\test.exe) anyways all help with this question would be much appreciated.

Jesse M.

Re: question on string and encryption sorta

jtmtv1816-Dec-02 10:45

jtmtv18

16-Dec-02 10:45

oops... had to fix some things.. here's the fixed question lol:

can any help me with a problem ! ... i have a encryption program that encrypts (anything) in RC2 or DES. the encryption method is in a static void and gets the (readfile) (writefile) (password)

the read file comes in the form of a full path name ie(c:\something\test.exe) then it is sent to the (readfile) part of encryption as a string. my question is how can i remove this directory name and just show the file name(test.exe) and send that too (writefile) with a *.enc extention on it but still preserving the original write name. !! i have not clue how to do this. all i really need to do is trim the string but how because what if the directory isnt the exsact same size as (c:\something\test.exe) anyways all help with this question would be much appreciated.

Re: question on string and encryption sorta

Rob Graham16-Dec-02 11:15

Rob Graham

16-Dec-02 11:15

<br />
using System.IO;<br />
...<br />
string justTheName = Path.GetFileNameWithoutExtension(theFullPathNameIHave);<br />
string theNameIWant = justTheName + ".enc";<br />
<br />

help require?

imran_rafique16-Dec-02 6:49

imran_rafique

16-Dec-02 6:49

I have created a service in c#.
And I am executing a Process.Start command in this code ( OF SERVICE PROJECT) .
that command(Process.Start ) is executing sucessfully for local drives but it throws Win32Exception (means There was an error in opening the associated file) at network path. for example path is \\computername\folder1\folder2\some.exe

AND it heapens only with Service type application all other applications are executing any process at network path (i.e \\computername\folder1\folder2\some.exe)successfully with this command(Process.Start).

Can any body tell how will I make my Service to execute any Process at network path?

r00d0034@yahoo.com

Re: help require?

Andres Manggini16-Dec-02 12:13

Andres Manggini

16-Dec-02 12:13

Hi,

Could it be that your service is running under an account that does not have sufficient permissions to access shared folders ?.

Hope this helps.

Andres Manggini.
Buenos Aires - Argentina.

Re: help require?

imran_rafique16-Dec-02 12:36

imran_rafique

16-Dec-02 12:36

it did not help at all.
service is running under admin account.

r00d0034@yahoo.com

Windows Form Control hosted in IE

LJMorsillo16-Dec-02 4:34

LJMorsillo

16-Dec-02 4:34

Here's a story... I hope someone can help me write a happy ending in time for Christmas!
I have a control

<code>namespace WvfCtlNet {
public class WvfCtl : System.Windows.Forms.UserControl .... </code>

which I'm hosting in IE

<OBJECT id="control" classid="http:WvfCtlNet.dll#WvfCtlNet.WvfCtl" name="control"> ...

I'm not getting anything other than a little box (place holder) when the page is displayed.

The control shows up in the GAC downloads ("gac /ldl") The version number agrees with the dll.

When I look in Internet Options-Settings..-View Files... I see the following entry:
?FusionBindError!name=WvfCtlNet.dll WvfCtlNet.WvfCtl

What the heck is this? (I think I know that Fusion is a technology related to 'no touch' installation but that's about it!)

Why doesn't my contol pop up? I works when hosted by an Windows Forms app.

Worst of all - This was working a week ago - I've not made any config changes, though I did recently install the Microsoft Web Services Extensions (WSE) pack.

I am flummoxed!

Thank you.
Sincerely, Lindsay

xor strings??

Karavaev Denis15-Dec-02 23:52

Karavaev Denis

15-Dec-02 23:52

How to make simple xor in C#?

=====================
http://wasp.elcat.kg

Re: xor strings??

Kannan Kalyanaraman16-Dec-02 0:13

Kannan Kalyanaraman

16-Dec-02 0:13

Hi,
If you are looking at nos. then you can use ^ operator.
For strings, you need to first convert them to bytes,

<br />
ASCIIEncoding enc = new ASCIIEncoding ();<br />
byte[] keybytes = enc.GetBytes (key);<br />

here key is of type string

once you have converted to bytes, you can work on them.
Hope this helps.

Cheers
Kannan

Re: xor strings??

Karavaev Denis16-Dec-02 0:46

Karavaev Denis

16-Dec-02 0:46

string txt1 = "some_text";
string txt2 = "anything_else";
ASCIIEncoding enc = new ASCIIEncoding();
ASCIIEncoding enc2 = new ASCIIEncoding();
byte[] kb1 = enc.GetBytes(txt1);
byte[] kb2 = enc2.GetBytes(txt2);
MessageBox.Show(kb1 ^ kb2);

Operator '^' cannot be applied to operands of type 'byte[]' and 'byte[]'

damm, what I did wrong?

=====================
http://wasp.elcat.kg

Re: xor strings??

Christian Graus16-Dec-02 0:54

Christian Graus

16-Dec-02 0:54

You need to ^ each byte, not the whole lot. You need to step through the strings, and can only perform the operation on the set of bytes that exists in both arrays, so unless the two strings are always the same length ( which they are not in your example ), I doubt you're going to get what you wanted.

Christian

No offense, but I don't really want to encourage the creation of another VB developer.
- Larry Antram 22 Oct 2002

C# will attract all comers, where VB is for IT Journalists and managers - Michael
P Butler 05-12-2002

Again, you can screw up a C/C++ program just as easily as a VB program. OK, maybe not
as easily, but it's certainly doable. - Jamie Nordmeyer - 15-Nov-2002

Re: xor strings??

Karavaev Denis16-Dec-02 1:06

Karavaev Denis

16-Dec-02 1:06

Ok, is there any other simple way to encode\decode some string?

=====================
http://wasp.elcat.kg

Re: xor strings??

Christian Graus16-Dec-02 1:09

Christian Graus

16-Dec-02 1:09

Yes, there is apparently heaps of encryption/decryption stuff in .NET, but I confess to not having used any of it, yet.

Christian

No offense, but I don't really want to encourage the creation of another VB developer.
- Larry Antram 22 Oct 2002

C# will attract all comers, where VB is for IT Journalists and managers - Michael
P Butler 05-12-2002

Again, you can screw up a C/C++ program just as easily as a VB program. OK, maybe not
as easily, but it's certainly doable. - Jamie Nordmeyer - 15-Nov-2002

Re: xor strings??

Kannan Kalyanaraman16-Dec-02 1:04

Kannan Kalyanaraman

16-Dec-02 1:04

You will have to iterate the array and do the operations individually on every byte.

<br />
 for(int i=0; i<10; i++)<br />
       kb1[i] ^= kb2[i];	<br />

Cheers
Kannan

Re: xor strings??

Daniel Turini16-Dec-02 0:22

Daniel Turini

16-Dec-02 0:22

Besides the above suggestion, you can after this, create a BitArray with the byte[] and use its Xor method.

I see dumb people

Dynamically Generating Data for a Waveform Graph Control

Matthew Alan Gray15-Dec-02 16:27

Matthew Alan Gray

15-Dec-02 16:27

I am currently developing a waveform graph control, and I am having difficulty in dynamically displaying multiple plots. Basically, I want to display anywhere from one to an undetermined number of plots on a single graph; I could use arrays to do this, but there would be difficulty resizing the arrays if I set the size of the arrays too low, and there would be wasted resources if I set the size of the array to high... What I need is an efficient way to add, update, and remove structures representing plot data that can be easily and efficiently resized -- is there a straightforward way to do this in C#??

Matthew Alan Gray, B.S.C.E.
Graduate Student, Mississippi State University
mag2@ece.msstate.edu

same COM object?

peterchen15-Dec-02 10:00

peterchen

15-Dec-02 10:00

And another one...

COM rules state that to check if two interfaces point to the same COM object, QI both interfaces for IUnknown directly, and compare the results.

How do I do that in C#?

If I could find a souvenir / just to prove the world was here [sighist]

Re: same COM object?

Rama Krishna Vavilala15-Dec-02 16:52

Rama Krishna Vavilala

15-Dec-02 16:52

Equals() method takes care of that for you or == operator.

The mistakes made in this API make me realise that Microsoft has become big enough that it can shelter morons. If anyone working for me wrote anything this bad and tried to release it, I would kill them and display the body as a warning to the rest of the team. - Christian Graus about C# - GDI+

ArrayList == vector and list ?

peterchen15-Dec-02 9:59

peterchen

15-Dec-02 9:59

Hi,

Is ArrayList a "reasonable" replacement for both vector and list?
It feels a bit weird, but the best I could find in the System.Collecitons namespace.

TIA
Peter

If I could find a souvenir / just to prove the world was here [sighist]

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