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Reading Serial Device (How To?)

Ariadne10-Jun-04 0:05

Ariadne

10-Jun-04 0:05

I want read data from Serial Device COM1. Is there an example, how to do it?

Ariadne

Re: Reading Serial Device (How To?)

Stefan Troschuetz10-Jun-04 0:28

Stefan Troschuetz

10-Jun-04 0:28

There are some articles here on CodeProject which may help you.
Article 1[^]
Article 2[^]

www.troschuetz.de

xmldocument and xhtml = sloooow

Roger Alsing9-Jun-04 23:20

Roger Alsing

9-Jun-04 23:20

Hi ,
im trying to parse xhtml code in a xmldocument object.

the thing is that if i try to parse the code from eg www.xhtml.org it takes 15 seconds to parse the doc (using .LoadXML(xmlstring))

BUT

if i set the documents .XMLResolver = null
it works much much faster (maybe 1-2 seconds for the same doc)
however , if the document contains tokens like & the parsing fails and crashes if the xmlresolver is null.

what can i do about this?

could it be that the xmlresolver actually downloads the "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd" that is specified in the xhtml code before it parses the code?
could i somehow make local copies of those files in that case and use those somethow?

//Roger

Re: xmldocument and xhtml = sloooow

Heath Stewart10-Jun-04 6:45

Heath Stewart

10-Jun-04 6:45

You should read the documentation for the XmlResolver property and class, which would answer your questions. Yes, for fully-trusted code (by default, code executed on and from your machine) the XmlDocument.XmlResolver is an XmlUrlResolver and will resolve DTDs. So, either extend XmlResolver or XmlUrlResolver and override ResolveUri so that it doesn't fetch external resources. Do override (unless you extend XmlUrlResolver, which already does this) GetEntity so that entities are resolved. Instantiate your implementation and set that as the XmlDocument.XmlResolver.

Here's a problem, though - if that entity is defined in the DTD (since XHTML doesn't define entities like  ) then you can't resolve it.

You could, however, attempt to resolve common entities (can be found on the W3C web site) as well as decimal and hexidecimal entities for character encoding, like &#XX; and &#xXX;. If the content author tries to include content using an entity, though, you'll have a problem (perhaps in this case you could fetch the DTD) before returning from your method - it may work).

Microsoft MVP, Visual C#
My Articles

Re: xmldocument and xhtml = sloooow

Roger Alsing10-Jun-04 23:37

Roger Alsing

10-Jun-04 23:37

Thanks for the info.

i solved it by embedding the standard dtd/ent files into my lib and made my xmlresolver use the embedded resources if they exist otherwise it will use the external resources.

//Roger

Re: xmldocument and xhtml = sloooow

Heath Stewart11-Jun-04 2:53

Heath Stewart

11-Jun-04 2:53

Good idea! I hadn't thought of doing that off the top of my head.

Microsoft MVP, Visual C#
My Articles

Life of application

quocbao9-Jun-04 21:55

quocbao

9-Jun-04 21:55

How to write a application that the user can only use 3 times.
I'm waiting for you.
Thank you.

Re: Life of application

Alex Getman10-Jun-04 1:24

Alex Getman

10-Jun-04 1:24

Maybe you shoud make a config file and also store some counter values in registry. On load your program should increment value in registry and if it's > 3 then your application should delete your file.

xedom developers team

Re: Life of application

Wackatronic10-Jun-04 4:55

Wackatronic

10-Jun-04 4:55

Alex Getman (leTaon) wrote:
then your application should delete your file

Bad practice to delete from a user's PC without notification or prior notification that after # uses the app will delete itself.

Yes, I program in VB, but only to feed my addiction to a warm place to sleep and food to eat!

Visit my Code Project blog (Mobile Audio project)[^]

Re: Life of application

Dave Kreskowiak10-Jun-04 4:56

Dave Kreskowiak

10-Jun-04 4:56

Weak. Very weak. There is nothing to stop the user from unstalling the app, deleting the registry keys and files you leave behind and then starting all over again. Or even just put the older values back into the registry and files.

Copy protection like this is nortoriously difficult to write. Google for "time limited software protection" and you'll come up with a bunch of results on libraries and packages that can be used in your project.

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

The file associated with FileStream

Meysam Mahfouzi9-Jun-04 21:40

Meysam Mahfouzi

9-Jun-04 21:40

The only way of associating a file with a FileStream object is thru its constructor, It means if I want to change the file name associated with some FileStream, I should re-instantiate it, doesn't it? Do you know any better way to do that?

Regards

I lock my house, I lock my car and I pull that zipper on my pants up several times a day for the sake of security. Smile | :)

Re: The file associated with FileStream

Heath Stewart10-Jun-04 4:25

Heath Stewart

10-Jun-04 4:25

A FileStream is tied to a native file handle, so yes, you must reinstantiate it. This is also why you should call Dispose on the FileStream when you're done. The file handle is a native type and unmanaged. Calling dispose closes that file handle. If you don't call Dispose, the file may remain locked until your application is closed.

Changing the file to which a FileStream object reference is not supported because of this fact. You can reassign the variable to a new FileStream, but that would reference a different object (and if you didn't call Dispose before changing the reference, you've just lost the ability to dispose it so that the native file handle is released).

Microsoft MVP, Visual C#
My Articles

How to add image property to UserControl?

luming11223344559-Jun-04 21:38

luming1122334455

9-Jun-04 21:38

I define a class based on UserControl
UserControl has no Image property ,I add one like this

public class mycontrol : System.Windows.Forms.UserControl
...
private Image m_image;
...
public Image Image
{
get
{
return m_image;
}
set
{
m_image = value;
}
}
I putted it into visual studio toolbox,In design time ,I load a picture , but Can't unload it and set it back to none.
for example , a button has the image property , if I want get this image out , just set the property to "" in property grid,then the button's Image change to none,how does it works?

it's my image property define wrong ?

Re: How to add image property to UserControl?

partyganger10-Jun-04 3:10

partyganger

10-Jun-04 3:10

Set the Image to null, that works for me (Try it with a button, asign an Image and add a click event that sets the Image property to null, the Image will disappear). If not, try calling the control's Invalidate() or Refresh() fucntions, since those will force the COntrol to repaint itself.

Re: How to add image property to UserControl?

Heath Stewart10-Jun-04 4:20

Heath Stewart

10-Jun-04 4:20

The Image class itself is attributed with the ImageConverter, which takes care of this automatically for you. There's nothing you really need to do. You could attribute your property with [DefaultValue(null)], which will allow you to right-click and select "Reset".

Microsoft MVP, Visual C#
My Articles

Re: How to add image property to UserControl?

luming112233445510-Jun-04 14:37

luming1122334455

10-Jun-04 14:37

Thanks you, That's just what I want.

Big Grin | :-D

send mail

ChangAli9-Jun-04 21:06

ChangAli

9-Jun-04 21:06

hi i want send mail from my program to next email ,for example Anzerato@hotmail.com ,but i can't,and error is :

System.web.HttpExeption:could not access 'CDO.Message'object.--->System.Reflection.TargetInvocationException:Exception has been thrown by the target of an invoction.--->System.Runtime.InteropServices.COMException(0x80040213):the transport failed to connect to server.
.
.
.

my program is :

MailMessage mail = new MailMessage();<br />
mail.From = "alichangizi@Hotmail.com";<br />
mail.To = "Anzerato@hotmail.com";<br />
mail.Subject = "Site Error";<br />
mail.Body = "OK";<br />
mail.BodyFormat = MailFormat.Html;<br />
MailMessage();<br />
try<br />
{<br />
   SmtpMail.SmtpServer = "localhost";<br />
   SmtpMail.Send(mail);<br />
}<br />
catch(System.Web.HttpException ehttp)<br />
{<br />
   Console.WriteLine("{0}", ehttp.Message);<br />
   Console.WriteLine("Here is the full error message output");<br />
   Console.Write("{0}", ehttp.ToString());<br />
}<br />

Re: send mail

Heath Stewart10-Jun-04 4:16

Heath Stewart

10-Jun-04 4:16

For one, you need to have the CDO component installed. The easiest way on Windows 2000, XP, and Windows Server 2003 is to install the SMTP services. Also, the SMTP server must relay for a particular domain. In your case, you must relay for hotmail.com.

Microsoft MVP, Visual C#
My Articles

Re: ListView

myNameIsRon9-Jun-04 20:44

myNameIsRon

9-Jun-04 20:44

Hi,
I was wondering if you can set a hidden value (would this be called a SelectedValue?) to each row in ListView? I'm populating the ListView from a DataSet. I want to be able to click on a row and have a form come up and ask for edit/delete this row (which would really update the DataSet and then reload the ListView to show the changes). Of course in order to do this, I need to have a corresponding ID for each row in the ListView that's retrievable from the selected row.

Thanks,
Ron

Re: ListView

Alex Getman10-Jun-04 1:29

Alex Getman

10-Jun-04 1:29

I faced with this problem not so long... Well, I created a hashtable and set keys from 0 to ListView.Count, and values were set just like in ListView, and on_klick I looked through hashtable and delete item that I need.

xedom developers team

Re: ListView

Serge Lobko-Lobanovsky10-Jun-04 2:08

Serge Lobko-Lobanovsky

10-Jun-04 2:08

Hi Ron,

Each ListViewItem has a Tag property which can be used for storing anything you need. In your case you could associate an ID or a datarow object with it.

Regards,
Serge (Logic Software, Easy Projects .NET site)

Re: ListView

myNameIsRon11-Jun-04 19:54

myNameIsRon

11-Jun-04 19:54

Thanks Serge!
Works great!

Ron

Access first form's control from the second form.

Titan59-Jun-04 19:27

Titan5

9-Jun-04 19:27

I created two forms: MainForm has a textbox tbBox1. I clicked a button btnOpen to open the second form (named Form2). Now I want to get or set the value of tbBox1 from the second form by clicking a button btnAccess. How can I do it? The MainForm was opened by the standard "Application.Run(Form MainForm);" and the second form was opened by "Form2 a = new Form2(); a.Show();" in btnAccess's OnClick event. I have made tbBox1 public but I couldn't access the instance of MainForm. The MainForm class' instance (an object) has no name when opened from Application.Run. Please help. Confused | :confused:

Re: Access first form's control from the second form.

fayth9-Jun-04 19:54

fayth

9-Jun-04 19:54

1. in form2, declare a member System.Windows.Forms.Form pForm;
2. overload the Form2's constructor
public Form2(System.windows.Forms.Form aForm)
{
pForm = aForm;
}

now you can acess Form1 like this.
pForm.xxxButton.Text = "test";

try it.

nhi

Re: Access first form's control from the second form.

fayth9-Jun-04 19:56

fayth

9-Jun-04 19:56

of course,when you create Form2 in form1 ,you should pass itself to the form2's contructor like
Form2 frm = new Form2(this);
frm.Show;

Smile | :)

nhi

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