a problem with threads. - C# Discussion Boards

Re: So Many ADO Data Providers Which Should I Use?

redfish3413-Sep-06 17:50

13-Sep-06 17:50

Sorry, i forgot about all the non-english speakers on this forum. KISS stands for Keep It Simple. I am not a programmer who always reaches for the latest technology to solve a problem because often the technologies are not mature and
have many undocumented problems.

I learned that ADO from VB6 is supported in NET for backward compatibility. That was confusing me. I now understand that OleDb is the choice to use for NET.

Setup doesnt generate reg keys

Gutec13-Sep-06 10:48

Gutec

13-Sep-06 10:48

Anyone seen something like this?

I have an application created with VS2003 with a setup project in the solution
nothing fancy. In this setup project I use the registry tab to instruct the install program to generate a certain registry key HKLM\Software\[Manufacturer]\etc...
But when I execute the install no such key is created!

Creating the key via a reg file works, meaning there is nothing wrong about the key
but despite the fact that I specify "create allways" nothing is ever created!

What could be wrong?

Ulf Rosvall

Print page with out a footer.

spark12800013-Sep-06 10:10

spark128000

13-Sep-06 10:10

I am able to print a webpage from a webBrowser using the WebBrowser.Print() method, but I need to know how to print the page without the header or footer. The Print() method automatically adds these to the printed page and I don't want it.
I know I can remove this by calling WebBrowser.ShowPageSetupDialog() and clearing the header and footer fields, but I don't want my users to have to do this manually.

Is there a way I can remove the header and footer from the printed page?

Scott Clayton

Get domain name from email address

MyRunner2313-Sep-06 9:34

MyRunner23

13-Sep-06 9:34

Hi All,

Anyone know how to separate email address into two parts (username + domain name)in C#?

Thanks

H

Re: Get domain name from email address

User 665813-Sep-06 9:45

User 6658

13-Sep-06 9:45

string mail = "someone@domain.org";

string user = mail.Substring(0, mail.IndexOf('@'));
string domain = mail.Substring(mail.IndexOf('@') + 1);

This is a very basic version. You could first do a check if the format is valid using a regular expression. But when you know you got a valid email, you may use this one.

regards

modified 12-Sep-18 21:01pm.

Re: Get domain name from email address

MyRunner2313-Sep-06 10:00

MyRunner23

13-Sep-06 10:00

I should say...

If I am going to check for specific domain name (for example: *ah* in yahoo.com) Thanks

Re: Get domain name from email address

spark12800013-Sep-06 10:21

spark128000

13-Sep-06 10:21

To check is a specified string is in another string use the following...

string test = "yahoo";
bool answer;

// answer is TRUE
answer = test.Contains("ah");

// answer is FALSE because "xp" is not in "yahoo"
answer = test.Contains("xp");

a problem with threads.

Green Fuze13-Sep-06 9:10

Green Fuze

13-Sep-06 9:10

Hi Everybody!

Man, what would I do without this board ?! Smile | :)

I think everything I know in programming is because of everybody's help in this board and code project's articles! THANKS! Big Grin | :-D

(REALLY!)

anyway, enough being emotional and all Smile | :)

.

I created a thread that receives a stream from the net to get a string.
I want that string to be displayed on the application textbox (or in other words, instant messanger).
The problem is that when I'm trying to assign StreamReader's text into textbox.text I'm getting exception saying that:

"Cross-thread operation not valid: Control 'textBox1' accessed from a thread other than the thread it was created on."

I REALLY don't understand why is that. is it because textbox1 is on ONE thread (the window form thread) and the StreamReader is on the other (the thread I created)?
if so, how can I fix it?!?!?! Confused | :confused:

That is the code of the service() method ran by the thread:

<br />
private void service()<br />
        {<br />
            while(true)<br />
            {<br />
                // get message from the socket.<br />
                socket = listener.AcceptSocket();<br />
                <br />
                try<br />
                {<br />
                    // create a stream object to get information from socket.<br />
                    Stream stream = new NetworkStream(socket);<br />
<br />
                    // streamreader to read from the socket<br />
                    StreamReader sr = new StreamReader(stream);<br />
<br />
                    // streamwriter to write to the socket<br />
                    StreamWriter sw = new StreamWriter(stream);<br />
                    sw.AutoFlush = true;<br />
<br />
                    string text = sr.ReadToEnd();<br />
                    this.textBox1.Text = text;<br />
<br />
                    stream.Close();<br />
                }<br />
                catch(Exception e)<br />
                {<br />
<br />
                    MessageBox.Show(e.Message);<br />
<br />
                }<br />
<br />
                socket.Close();<br />
            }<br />
        }

Thanks!!!!

Re: a problem with threads.

Stefan Troschuetz13-Sep-06 9:20

Stefan Troschuetz

13-Sep-06 9:20

Green Fuze wrote:
I REALLY don't understand why is that. is it because textbox1 is on ONE thread (the window form thread) and the StreamReader is on the other (the thread I created)?

Exactly. You're not allowed to access controls from a thread other than the one they were created on. Use Invoke or BeginInvoke to resolve the problem. There's also a very good article on this topic here on CP Smile | :)

Search for Invoke and you should find it.

"Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning." - Rick Cook

www.troschuetz.de

Re: a problem with threads.

Green Fuze13-Sep-06 9:25

Green Fuze

13-Sep-06 9:25

Thanks alot! Smile | :)

I'll try that.

by the way, I'm stealing your signature for my personal mail, ok? (its hilarious!)

Re: a problem with threads.

Guffa13-Sep-06 11:30

Guffa

13-Sep-06 11:30

Green Fuze wrote:
I'm stealing your signature for my personal mail, ok?

Why wouldn't it be? It's a quote, so he "stole" it himself. Wink | ;)

---
b { font-weight: normal; }

Quick generics q

thepersonof13-Sep-06 8:26

thepersonof

13-Sep-06 8:26

Hey

I am just starting with generics:

How can I convert a float to type T (which is either a float or a double and is iconvertible)?

I get the error:

Cannot convert type 'float' to 'T'

Problem 2...
The error:

Operator '*' cannot be applied to operands of type 'T' and 'T'

when I multiply two numbers
What can I do about this? Does float inherit from some class that defines basic mathematical operations?

All help is greatly appreciated

Re: Quick generics q

Rob Graham13-Sep-06 8:50

Rob Graham

13-Sep-06 8:50

Perhaps a snippet or two of your code would help?

Re: Quick generics q

thepersonof13-Sep-06 9:47

thepersonof

13-Sep-06 9:47

It's rather simple:

#1:

this.X = (T)xValue;

where this.X and xValue is float and T is double or float.

#2:

Math.Sqrt( X*X+Y*Y);

where X,Y are of type T which is either double or float (and impleements iconvertable).

thank you!

Re: Quick generics q

Nader Elshehabi13-Sep-06 10:35

Nader Elshehabi

13-Sep-06 10:35

Hello

Actually this is not the snippet he was lokking for. You should post the definition of your generic class/method itself rather than just its call.
Also don't forget to check "Ignore HTML tags..." checkbox present below the editting textbox.

Regards

implementing drag drop ability with figures

ssoffline13-Sep-06 8:16

ssoffline

13-Sep-06 8:16

hi frens

i wan't to develop a software like circuitmaker, that's capable of making DFD's for that i need to implement drag and drop of objects , i have no idea how to make that happen , so that they can be drawn as well as scaled,etc. a solution with XML shall be a great help

Sameer Sood Blush | :O

Re: implementing drag drop ability with figures

Nader Elshehabi13-Sep-06 9:27

Nader Elshehabi

13-Sep-06 9:27

Hello

ssoffline wrote:
i need to implement drag and drop of objects

here take a look at these two articles:
How to tutorial (very good)[^]
TreeViewDragDrop[^]

ssoffline wrote:
can be drawn as well as scaled

You can do all that using a Graphics object.

ssoffline wrote:
a solution with XML shall be a great help

Now that's a bit weird!!

Regards

report viewer

TAREQ F ABUZUHRI13-Sep-06 7:54

TAREQ F ABUZUHRI

13-Sep-06 7:54

how can set print layout and zoom

by default as in this image
http://www.shoppinp.com/report.gif

??

Palestine

Get the width of a string in C# without Graphics

Goebel13-Sep-06 7:48

Goebel

13-Sep-06 7:48

I'm developing a chart library with C# that outputs a SVG (Scalable Vector Graphic) file. SVG is pure XML output so there are no WinForms involved whatsoever.

In order to avoid overlapping text I'd like to use the MeasureString(...) and then set text properties (font size) accordingly, if overlap occurred. The Graphics object seems to be a prerequisite as it provides MeasureString(...). Is there a way of using MeasureString(...) functionality without using Graphics.

I've seen a possible solution which creates a random Graphics object out of a Bitmap which can then be "abused" to provide MeasureString(...) functionality:

<br />
Bitmap bmp = new Bitmap(1,1); <br />
Graphics g = Graphics.FromImage(bmp); <br />
g.MeasureString(...)<br />

Would you call this an elegant solution or is it just a workaround?
Once again: Is there another possibility of calculating the width of a string without Graphics?

Cheers.

Re: Get the width of a string in C# without Graphics

Nader Elshehabi13-Sep-06 10:28

Nader Elshehabi

13-Sep-06 10:28

Hello

I don't know about SVG formats but isn't displaying the text without overlapping would be the problem of the form that will read the file??

Anyway, if you want a graphics object, you don't need a bitmap, simple make call CreateGraphics() from your form -you still got one, right?-, and it will return a graphics object to work with.

Regards

Re: Get the width of a string in C# without Graphics

Goebel13-Sep-06 11:07

Goebel

13-Sep-06 11:07

Hello,

thanks for your reply.

Let me make things clearer.
SVG is a vector graphics format based on XML. The .NET application I'm currently developing generates such a SVG file. In this file various shapes, text elements, paths are described. Once the file is created the job is done.
As mentioned there are also text elements in the SVG, e.g. "This is a text" rendered as Arial, Bold, 12pt. MeasureString(...) would be ideal to calculate the size of any text although I'm eventually creating a SVG file.

Bear in mind: There is no form involved, so CreateGraphics() can't be invoked. Any further advice?

Thanks

Re: Get the width of a string in C# without Graphics

Nader Elshehabi13-Sep-06 11:26

Nader Elshehabi

13-Sep-06 11:26

Well, I guess then that you are developing a dll.

Even if there is no forms in your application, you can reference to System.Windows.Forms namespace and use TextRenderer class. There is a static method called MeasureText() that does the same thing.

Regards

Re: Get the width of a string in C# without Graphics

Goebel13-Sep-06 12:16

Goebel

13-Sep-06 12:16

You are right, I'm developing a dll.

Unfortunately, I'm using .NET Framework 1.1 - there isn't such a class available. Any other ideas?

Thanks.

Re: Get the width of a string in C# without Graphics

Nader Elshehabi13-Sep-06 12:41

Nader Elshehabi

13-Sep-06 12:41

Great!! I love this mission impossible style questions! Cool | :cool:

Theoretically this idea should work, but TEST IT as I haven't tested it yet.

1- Download .net 2.0 framework
2- Install it on your PC
3- In your project explicitly reference to that System.Windows.Forms dll. Its path should be "C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\System.Windows.Forms.dll" or something similar.
4- Use the appropriate class
5- Install .Net 2.0 framework on the target machine either in your setup project if you have one or include it as a minimum requirement in your documentation.

Otherwise you'd have to make API calls -if there is any, I don't know- or do your measurements manually Dead | X|

.

Oh!! One last thing.. Don't forget to tell me if it actually worked Laugh | :laugh:

Regards

Re: Get the width of a string in C# without Graphics

Goebel13-Sep-06 21:59

Goebel

13-Sep-06 21:59

Just tried .NET Framework 2.0 on a different machine. TextRenderer does it's job, thanks for your advice. Although the result is not that precise (same with MeasureString(...)) - I might provide my own method to measure strings. Anyway, I'll let you know!

Cheers.

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