C# Discussion Boards - CodeProject

jemi jets9-Nov-06 9:37

9-Nov-06 9:37

thanks for ur help..i have fixed my error..and about the typing lessons stuff..iam working on it man..cheers up Smile | :)

Re: how select adata from sql by c#

ed^nrgc9-Nov-06 6:45

ed^nrgc

9-Nov-06 6:45

jemi jets wrote:
note: the fname int ist sec columns and the dno in the 4th cloumn.>>>waiting...

Need typing lessons? Confused | :confused:

What exactly is the error?

Re: how select adata from sql by c#

Christian Graus9-Nov-06 9:09

Christian Graus

9-Nov-06 9:09

FRom the format of your message, I'd guess the code has a typo.

Should ssn be in single quotes ( is it a text field ) ?

exception: Cannot modify the Items collection when the DataSource property is set.

Saira Tanwir9-Nov-06 3:54

Saira Tanwir

9-Nov-06 3:54

hi there
i'm trying to bind data from a datatable to a combobox.
when i try to do it with the datasource property, it gives me the exceptionCannot modify the Items collection when the DataSource property is set.
i have previously bound data using the datasouce property to another combo on the same form.
can anyone help??? Sigh | :sigh:

Saira

Re: exception: Cannot modify the Items collection when the DataSource property is set.

Parwej Ahamad9-Nov-06 5:30

Parwej Ahamad

9-Nov-06 5:30

here are many stupid bugs with Items and DataSorce. You cannot use DataSource if you use Items. You cannot use Sorted if you use DataSource and so on... Cry | :((

But to your question: before clearing the ComboBox, unselect any selected item (reset it to null).

Or change DataSource this way:
1.) set DataSource to null
2.) set another object to DataSource

Parwej Ahamad

Re: exception: Cannot modify the Items collection when the DataSource property is set.

Saira Tanwir9-Nov-06 21:57

Saira Tanwir

9-Nov-06 21:57

thanks for the big help
perwaiz

regards

Saira

Re: exception: Cannot modify the Items collection when the DataSource property is set.

Parwej Ahamad10-Nov-06 5:05

Parwej Ahamad

10-Nov-06 5:05

Thanks Dear,

If u have further problem u can mail me.
g_parwez@rediffmail.com

Parwej Ahamad

g_parwez@rediffmail.com

Garbage Collection ? or something else ?

C#_Dude9-Nov-06 3:41

C#_Dude

9-Nov-06 3:41

Hi !

I have an app created with C# with an MDI and a bunch of forms/reports.

Besides the MDI, I also have a form that can help users by showing what forms are there in the app. This form has BUTTONS only. and When any of them is pressed, that particular form will be opened and added to the MDI ... so on and so forth.

The problem is, when a FORM is closed, its memory is not released, because that other form with BUTTONS still has its reference. And I guess Garbage collection anticipates it might be used again.

How can I explicitly FREE MEMORY of a FORM OBJECT in a situation like this ?

I have tried from within the FORM_CLOSING, no luck.

Thanks much

Re: Garbage Collection ? or something else ?

Guffa9-Nov-06 3:52

Guffa

9-Nov-06 3:52

C#_Dude wrote:
The problem is, when a FORM is closed, its memory is not released, because that other form with BUTTONS still has its reference.

Are you sure? Why would that form hold on to the references?

C#_Dude wrote:
How can I explicitly FREE MEMORY of a FORM OBJECT in a situation like this ?

Normally you never free memory, you only make sure that the objects are properly closed and get rid of the reference to them, then the garbage collector will eventually collect them.

It's normal for objects to remain in memory a while after you have released them. The garbage collector makes a collection when it's convenient or when it's needed. There is no reason to collect objects when there is no immediate demand for memory.

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

Re: Garbage Collection ? or something else ?

Jon Hulatt9-Nov-06 3:53

Jon Hulatt

9-Nov-06 3:53

The garbage collector frees an object when there are no references left. So, if your buton retains a reference to a form, then it will not be GC'd. The garbage collector does not anticipate anything. Once you've removed your last reference to an instance of an object, you cannot get that instance back again at all.

How does your button-form know "what forms are there in the app"?

Do you mean it shows what forms are open and displayed?

If so, then - the standard convention is to use entries on the Window menu for that- it's been standard windows UI behaviour since the 3.0 days at least.

using System.Beer;

datagridview and xml

Yustme9-Nov-06 3:09

Yustme

9-Nov-06 3:09

Hi,

I have an xml file which contains the history of send sms messages.

I loaded the xml file into a datagridview. The problem is, i don't know how i can load the data back into their controls.

I got two controls where data can be typed in. The first one is phone number which is a textbox.

And a richtexteditor where the message can be typed in. But my xml file contains 3 nodes.

Node 1 = date and time in ticks.
Node 2 = phone number.
Node 3 = message.

So if a row in the datagridview gets clicked/selected, it should load the phone number in the textbox and the message in the richtextbox.

Thanks in advance!

Re: datagridview and xml

Drew McGhie9-Nov-06 9:30

Drew McGhie

9-Nov-06 9:30

Check out Databinding.

The idea is that you have a BindingSource object that acts as the intermediary between the DataSource (the datatable with the data) and the input forms.

check out the CP article here for more specifics: http://www.codeproject.com/vb/net/databindingconcepts.asp[^] Its in vb, not C#, but the concepts are the same, and the displays will really help explain it to you.

Font conversion when XML serialize

topcatalpha9-Nov-06 3:09

topcatalpha

9-Nov-06 3:09

Hi,

I'm using serialize to export an object to XML and the object has a Font property.
All goes allright the font is stored with dot comma separator (when bold etc is enabled) in the XML file. so far so good when i restore the object on the same PC.

Here's the problem :

When restoring the object from XML on another PC with different regional settings the conversion fails because it expects a comma separator instead of dot comma.. (for the Font property)

When changing the list separator on the regional settings in windows XP, the problem disapears. But ofcours we cannot ask this to do at our customers. Smile | :)

So i gues i can change this regional settings in my software using the Cultureinfo.
But after changing the Textinfo.ListSeparator tot ";" or "," the problem remains and no changes are made when saving or restoring the XML file..

has anyone any idea how the solve this problem ?

Greetz and Thx

Kurt

Re: Font conversion when XML serialize

topcatalpha14-Nov-06 2:58

topcatalpha

14-Nov-06 2:58

Hi,

Seems i always have to post my own solution Smile | :)

OK,

Passing your own culture info to the fontconvertor seems to be a solution to my problem ....

"ConvertedFont" is a string containing the Font information.

FontConverter Tmp = new FontConverter();
ITypeDescriptorContext Dscrptr = null;
CultureInfo Cltr = new CultureInfo("nl-BE");
return (Font)Tmp.ConvertFromString(Dscrptr, Cltr, ConvertedFont);

greetz

Kurt

Unable to start debugging In VS2005

GnanaprakashJebaraj9-Nov-06 2:32

GnanaprakashJebaraj

9-Nov-06 2:32

I have sample in which is running in VS2003 and the sample which I tried to run in VS2005 (V2.0.50727) gives me the below error.

Unable to start debugging. Iam getting the error message as given below.

1. The application you are trying to debug uses a version of the Microsoft .NET Framework that is not supposed by the debugger.

2. The debugger has made an incorrect assumption about the Microsoft .NET Framework version your application is going to use.

3. The Microsoft .NET Framework version specified by you for debugging is incorrect.

For solving this issue I did

In the Registry Editor, open the HKEY_LOCAL_MACHINE folder.

Navigate to: HKEY_LOCAL_MACHINE\Software\Microsoft\VisualStudio\8.0\AD7Metrics\Engine\{449EC4CC-30D2-4032-9256-EE18EB41B62B}

then created new string "CLRVersionForDebugging" and value "V2.0.50727" . After doing all this things still Iam getting the same debug error.

Pls anybody can give solution for this problem.

Re: Unable to start debugging In VS2005

Yustme9-Nov-06 3:57

Yustme

9-Nov-06 3:57

Hi GnanaprakashJebaraj,

Usually, if you start a project which is programmed in an older version of IDE than the one in which you load it, it asks you if you want to convert it.

Did you got that message? If so, did you do that?

Re: Unable to start debugging In VS2005

GnanaprakashJebaraj9-Nov-06 17:38

GnanaprakashJebaraj

9-Nov-06 17:38

Yes, we got the message.After converting we try to debug the application It gives the debugger error.

For example download this sample and try to run

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnexcl2k2/html/odc_xlrtdvbnet.asp

This application open's an Excel.In Excel formula bar paste the following formula

=RTD("Stock.Quote", , "MSFT", "Open")
=RTD("Stock.Quote", , "MSFT", "Last")

formula will return some random value in Excel.For this sample I was able to debug and run in VS2003 but in VS2005 Iam getting debugger error.

NumericUpDown

sujithkumarsl9-Nov-06 2:26

sujithkumarsl

9-Nov-06 2:26

How to set a maximun value in NumericUpDown,while using a keyBoard

My small attempt...

Re: NumericUpDown

Ashish Derhgawen9-Nov-06 3:29

Ashish Derhgawen

9-Nov-06 3:29

Probably working on the numericUpDown_KeyDown event would help.

Try something like:

if (e.KeyCode > Keys.D5)<br />
{          <br />
e.SuppressKeyPress = true;<br />
}<br />

This will prevent the user from entering a digit greater than 5.

Hope that helps,
Ashish

Time flies like an arrow;
Fruit flies like a banana.

Ashish Derhgawen - http://ashishrd.blogspot.com[^]

Re: NumericUpDown

sujithkumarsl9-Nov-06 18:40

sujithkumarsl

9-Nov-06 18:40

Thanks for replying.Unfortunatly my problem is not fixed.I got a error like this
"'System.Windows.Forms.KeyEventArgs' does not contain a definition for 'SuppressKeyPress'".

Expecting a reply

My small attempt...

Re: NumericUpDown [modified]

Ashish Derhgawen9-Nov-06 22:12

Ashish Derhgawen

9-Nov-06 22:12

It seems like you're using an older version of the .NET Framework. System.Windows.Forms.KeyEventArgs.SuppressKeyPress is only supported in versions 2.0 and 3.0. Well, this isn't the end of the world..there's always an alternative. Smile | :)

Try this in the KeyPress event:

private void numericUpDown1_KeyPress(object sender, KeyPressEventArgs e)<br />
{<br />
    if (e.KeyChar >= (char)Keys.D5)<br />
    {<br />
        e.Handled = true;<br />
    }<br />
}

This should prevent the user from entering keys greater than 5 on the keyboard. This won't work if the user uses the numeric keypad. Just play with the ">= (char)Keys.D5)" part to get the desired results.

Hope that helps,
Ashish

-- modified at 4:22 Friday 10th November, 2006

Time flies like an arrow;
Fruit flies like a banana.

Ashish Derhgawen - http://ashishrd.blogspot.com[^]

Re: NumericUpDown

sujithkumarsl9-Nov-06 22:51

sujithkumarsl

9-Nov-06 22:51

I will check,thanks a lot.If i got the result i wil msg u.If u got the key try to infrom me.

My small attempt...

Re: NumericUpDown

sujithkumarsl10-Nov-06 1:27

sujithkumarsl

10-Nov-06 1:27

Do u feel,is there any other method.Actually i want to restrict the number greater than 10000.

My small attempt...

Regarding 70-315

Mirunab9-Nov-06 1:56

Mirunab

9-Nov-06 1:56

Hi All,
Am planning to take a test of 70-315(C#-Web application)by next week.Can anyone help me with details of latest pattern of the exam.
Thanks in Advance.

Thanks,
Mirunab

Re: Regarding 70-315

Colin Angus Mackay9-Nov-06 3:27

Colin Angus Mackay

9-Nov-06 3:27

Mirunab wrote:
Can anyone help me with details of latest pattern of the exam.

What does that mean?

I went along to the exam centre, signed in, was shown to a computer and they logged me into the exam. I then answered the questions and at the end of the exam I went back to the receiption where I received a print out of my grade.

*** Developer Day 4 in Reading, England on 2nd December 2006 - Registration Now Open ***

Upcoming Scottish Developers events:
* Developer Day Scotland: are you interested in speaking or attending?
My: Website | Blog

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.