C# Discussion Boards - CodeProject

parvinder sehrawat3-Oct-05 3:30

3-Oct-05 3:30

Hi guys

i need help for developeing the graphic component for polar chat. i need some sample code for developing the polar chart??

code is -
//This program graphs the equation r = A * Sin(B * t).

PointF[] objAr;

double t = 0;
int i=0;
double dt = PI / 100;

do
{
objAr=new PointF[i+1];
r = System.Math.Cos(t) * System.Math.Sin(t);
//r = 3*System.Math.Sin(t);
//r = valueA * System.Math.Sin(valueB * t);
if (r>=0)
{
r=System.Math.Sqrt(r);
x = (r * System.Math.Cos(t))+50;
y = (r * System.Math.Sin(t))+50;
}
PointF PointFn=new PointF(Convert.ToSingle(x),Convert.ToSingle(y));
objAr[i]=PointFn;

t = t + dt;
i++;
}while(t <= 2 * PI);
objGraphics.DrawCurve(new Pen(new SolidBrush(Color.Red),2),objAr);

but this code generate only single line not curve according to values.

Re: Polar Graph in c#??

Robert Rohde3-Oct-05 7:20

Robert Rohde

3-Oct-05 7:20

Well I think its because you recreate the Point array objAr in every iteration. As you don't seem to know how many points will be in the result I would recommend storing all points in an ArrayList and copying them to an array afterwards:

PointF[] objAr;

double t = 0;
double dt = PI / 100;
ArrayList pointsList = new ArrayList();
do
{
r = System.Math.Cos(t) * System.Math.Sin(t);
//r = 3*System.Math.Sin(t);
//r = valueA * System.Math.Sin(valueB * t);
if (r>=0)
{
r=System.Math.Sqrt(r);
x = (r * System.Math.Cos(t))+50;
y = (r * System.Math.Sin(t))+50;
}
PointF PointFn=new PointF(Convert.ToSingle(x),Convert.ToSingle(y));
pointsList.Add(PointFn);

t = t + dt;
}while(t <= 2 * PI);
PointF[] objAr = new PointF[pointsList.Count];
pointsList.CopyTo(objAr);
objGraphics.DrawCurve(new Pen(new SolidBrush(Color.Red),2),objAr);

Haven't checked it for correctness but it should at least give you the idea of what I mean.

Writing code for Credit Card Reader in C#

CharlyBrownson3-Oct-05 3:05

CharlyBrownson

3-Oct-05 3:05

Hi guys, I work maintaining a system in C# and I was assigned
to write some code that will take take the credit card number
read by the credit card machine and automatically put that into
a text box in the program so the user doesnt have to manually type
it in once they scan the credit card. We have a NetCom K23P by
tillsmith and I dont know how to go about this. It has an RS232
connector but thats about it. Does any one have experience with this?
Thanks in advanced guys.

-Charles

Re: Writing code for Credit Card Reader in C#

g00fyman3-Oct-05 4:09

g00fyman

3-Oct-05 4:09

.NET 2 makes this a snap using System.IO.Ports u can easily monitor the COM ports

otherwise u could use MSComm COM/OCX control, or use interop

these devices usually only have ASCII text from the reader, not sure about your model

basically u need to monitor the port for activity, when u detect something on the port identify that it is in the correct format, ie., check card track data formats then read the data onto your form.

i created a service to do this that maintains the form status so if a user swipes a card and the form is closed the service re-opens it an populates the form with the data.

the service just runs its own thread to monitor the port, basically blocking on port activity rather than polling the port continuously.

hope that helps,
g00fy

Re: Writing code for Credit Card Reader in C#

CharlyBrownson3-Oct-05 14:25

CharlyBrownson

3-Oct-05 14:25

Thanks so much for your help g00fy! I think I will go
with the simplest way, which would probably be
using .NET 2's System.IO.Ports...

-Charly

Re: Writing code for Credit Card Reader in C#

g00fyman3-Oct-05 15:44

g00fyman

3-Oct-05 15:44

only trouble there is that the beta is timebombed so if its a commercial app you may need to be aware of that. im not sure if only the IDE stops working or if all apps created in it stop as well Frown | :(

hopefully full release of .NET 2 is not far off, its alot better

regs,
g00fy

C# and authenticating with LDAP

ehuysamer3-Oct-05 2:49

ehuysamer

3-Oct-05 2:49

Hi
I was wondering if anyone could offer some advice on authenticating a .NET application with LDAP. The code seems to work fine with AD, but fails with LDAP:

(extract)

DirectoryEntry entry = new DirectoryEntry("LDAP://testdomain/DC=testdomain", "testdomain/testuser", textPassword.Text);<br />
<br />
Object obj = entry.NativeObject;<br />
DirectorySearcher search = new DirectorySearcher(entry);<br />
search.Filter = "(SAMAccountName=testuser)";<br />
search.PropertiesToLoad.Add("cn");<br />
SearchResult result = search.FindOne();<br />
<br />
if (null == result)<br />
{<br />
.<br />
.<br />
.<br />
}

The test PC runs on a Windows XP box with .NET Framework 1.1, and is bound to the respective authentication server every time.
The authentication server is a Mac OS X 10.4 server running LDAPv3.

Any suggestions?

Passing Passwords ARGS

har04mich3-Oct-05 2:30

har04mich

3-Oct-05 2:30

I have a login web page writtin in C#.Net, when the user logs to goes against AD, if that is successful, then it passes the user name and password to an exe that is also written in C#.Net that checks if the user name is sync with our other network applications.

The problem I am having is that user can not have any spaces in there password, if they do it will get chopped of any not sync the correct password to the apps, any ideas on how I can fix this problem?

Thanks

har04mich

Re: Passing Passwords ARGS

ehuysamer4-Oct-05 4:25

ehuysamer

4-Oct-05 4:25

Have a look at the parameters that you are passing. You might try putting quotes around them: "
This will not parse as part of the parameters; but be sure to escape any existing "s appropriately.

By the way, its extremely bad practice passing passwords as command-line parameters: I'd suggest trying to have the password checked by your web app against the domain, and then just passing the user's name itself to your separate application to do whatever it does with it.

GDI+ Problemo

XeoN-Kc3-Oct-05 2:05

XeoN-Kc

3-Oct-05 2:05

Hi guyz.

I am trying to lock the bits of a gif image which is 32-bit. However, I am getting an invalid parameter on this code :

BitmapData bmData = b.LockBits(new Rectangle(0, 0, b.Width, b.Height), <br />
        ImageLockMode.ReadWrite, PixelFormat.Format32BppArgb);

where b is the bitmap variable in which I load the image in!

Can any body help out on this? because I really have no idea now...since in 24-bit withPixelFormat24BppRgb(bmp + jpg) worked correctly!

Confused | :confused:

To Dare Is To Do Cool | :cool:

Re: GDI+ Problemo

leppie3-Oct-05 3:12

leppie

3-Oct-05 3:12

Try 8bitIndexed pixel format

^{xacc-ide 0.0.15 now with C#, MSIL, C, XML, ASP.NET, Nemerle, MyXaml and HLSL coloring - Screenshots}

Re: GDI+ Problemo

Andrew Kirillov3-Oct-05 3:44

Andrew Kirillov

3-Oct-05 3:44

Hello

Why do you think your GIF image is 32-bit ? You can check the PixelFormat property and you will see, that it's Format8bppIndexed.

You can try to use ImageLockMode.ReadOnly mode or lock your image with PixelFormat.Format8bppIndexed or convert your image to 32-bit before (which will be useful if you are planning some image processing routines).

With best regards,
Andrew

Re: GDI+ Problemo

XeoN-Kc3-Oct-05 7:55

XeoN-Kc

3-Oct-05 7:55

Yep that's actually what I'm trying to do!

To convert to 32-bit from 8 bit index....how?? bcos I really do not know!

Thanks guys

To Dare Is To Do

Re: GDI+ Problemo

Andrew Kirillov3-Oct-05 9:40

Andrew Kirillov

3-Oct-05 9:40

Hello.

You can use the next code:

// create new image with desired pixel format
Bitmap bmp = new Bitmap(width, height, PixelFormat.Format32bppArgb);

// draw source image on the new one using Graphics
Graphics g = Graphics.FromImage(bmp);
g.DrawImage(src, 0, 0, width, height);
g.Dispose();

With best regards,
Andrew

Why Leave the user defined control make the changes of the combobox?

Ming Luo3-Oct-05 1:51

Ming Luo

3-Oct-05 1:51

Hi all
I met this problem several times. There are a combobox and a userdefined control in a form. First I select an item from a comboboxlist, then I focus the cursor into the user defined control. When I leave the user defined control, the combobox selected item will be changed automatically, it generally be set to blank. I met this problem every time I want to integrate a user control into a form with a combobox. I don't understand this. Does anybody meet this problem before???
Thanks in advance!

Asura

Binding a property to a textbox problem

Ming Luo3-Oct-05 0:53

Ming Luo

3-Oct-05 0:53

Hello Everybody!!!
I build a Machine class with its properties. Then I try to bind a textbox.Text to one of the machine properties. It works fine. But when I change the property in code, the textbox.Text doesn't change synchronisely. I try to use the CurrencyManager to refresh the databinding. But because the binding is not an array or datatable, I can't get the CurrencyManager from the BindingContext. I want to use the BindingManager to achieve the synchronisation. But I don't know if there is a way to do it. Could somebody tell me how to make the textbox.Text synchronisely display the result as the machine property please???
Thanks in advance

Asura

Change another forms controls properties

freshonlineMax2-Oct-05 23:52

freshonlineMax

2-Oct-05 23:52

Hi!
I have a problem and i spend long time to solve it, but I couldn't.
I have one mdi form and a child form, i want to change one of mdi forms controls properties by pressing a button in child form. i did this :

mdiForm copymdiForm = New mdiForm() ;

and when I type "copymdiForm." i cant see mdi forms controls! D'Oh! | :doh:

it workes in Vb.Net but not in C#.
Can anybody help me about this ?
So Thanks for your attends to my request. Smile | :)

-- modified at 5:53 Monday 3rd October, 2005

Re: Change another forms controls properties

Wjousts3-Oct-05 2:52

Wjousts

3-Oct-05 2:52

Are the forms controls marked as private? If they are you won't be able to see them outside of the form's class. Mark them as public or provide a public method to set them.

Re: Change another forms controls properties

freshonlineMax3-Oct-05 19:15

freshonlineMax

3-Oct-05 19:15

Hello Dear Wjousts and so Thanks about your advice.
I changed Second forms controls modifiers property from Private to Public, and, and, it worked!!! Ok i did this before but this time it worked. If i can do something for you please mail me. I'm working Database programming (Ado.Net & SQLServer2000).
Bye Bye Smile | :)

TransparencyKey does not work in combination with Opacity!

Martin#2-Oct-05 22:59

Martin#

2-Oct-05 22:59

Hello Everybody!

I have a VS 2003 application where I have a Form (Formx.Show();).
I tried to make an fading style by changing the "Opacity" Property.
This works so far, but the transparent color (Property "TransparencyKey") is then painted on the screen.
If I do not change the Opacity, the Trancparent Color is not painted.

I hope somebody has an workaround for my problem.

Thank you for your time.

Martin

call the function from CODE BEHIND page to HTML

mohd rafi2-Oct-05 22:30

mohd rafi

2-Oct-05 22:30

i have function in code behind,i want how to call the that function in html page

m mohamad rafi

-- modified at 4:30 Monday 3rd October, 2005

Pointers in struct to itself

Dominik Reichl2-Oct-05 22:13

Dominik Reichl

2-Oct-05 22:13

Hi!

I want to define a structure that has 2 pointers to the same type as itself. For example, think of a Huffman tree node. In C++ we did it like this:

typedef struct
{
    unsigned int code;
    unsigned int count;
    HUFFTREENODE *l;
    HUFFTREENODE *r;
} HUFFTREENODE;

Now, how can we do the same in C#? I tried this:

public struct HuffTreeNode
{
    uint code;
    uint count;
    HuffTreeNode l;
    HuffTreeNode r;
}

But it gives me an error that this would create a loop in the struct...

Thanks in advance and best regards
Dominik

_outp(0x64, 0xAD);
and
__asm mov al, 0xAD __asm out 0x64, al
do the same... but what do they do??
(doesn't work on NT)

Re: Pointers in struct to itself

Mathew Hall2-Oct-05 22:44

Mathew Hall

2-Oct-05 22:44

You'd probably want to do something like:

[StructLayout(LayoutKind.Sequential)]
public struct HuffTreeNode
{
    uint code;
    uint count;
    IntPtr leftNode;
    IntPtr rightNode;
}

and then use Marshal.StructureToPtr[^] and Marshal.PtrToStructure[^] to convert the struct to/from a pointer

"I think I speak on behalf of everyone here when I say huh?" - Buffy

Re: Pointers in struct to itself

Dominik Reichl2-Oct-05 22:56

Dominik Reichl

2-Oct-05 22:56

Thanks! Interestingly, when I replace 'struct' by 'class', the code I posted first compiles nicely (why??)...

What do you think is more efficient? Making the thingy a class or leaving it as struct and using Marshal.etc? I won't have that many nodes, only about 66000...

Thanks again and best regards
Dominik

_outp(0x64, 0xAD);
and
__asm mov al, 0xAD __asm out 0x64, al
do the same... but what do they do??
(doesn't work on NT)

Re: Pointers in struct to itself

Daniel Turini2-Oct-05 23:11

Daniel Turini

2-Oct-05 23:11

Dominik Reichl wrote:
What do you think is more efficient? Making the thingy a class or leaving it as struct and using Marshal.etc? I won't have that many nodes, only about 66000...
Structs should (mostly) only used for Interop calls. As it seems you're designing a Huffman class library, with no interop calls, I'd create it as a class.

I don't see dead pixels anymore...
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