ComboBox and DataSource attribute - C# Discussion Boards

sam#25-Oct-06 7:58

25-Oct-06 7:58

there is no such facility provided by the data grid.you can do two things either make a custom control data grid or insert a new row in the table with desired values

sameer

Proper way to handle single instance application and multithreading

Dan Neely25-Oct-06 3:47

Dan Neely

25-Oct-06 3:47

I have an app that currently creates several worker threads in the mainform constructor. I'm currently modifying it to only allow one running copy at a time. The issue I have is that since the threads are created in the constructor prior to starting the app, when the already running check is done and the main thread isn't started they're orphaned and the 2nd instance remains hiding in the process list.

I've found two possible workarounds for this. The first is to move the thread creation from the form constructor to the OnLoad event, so that they're never created on the aborted 2nd instance attempt. The second is to explicitly create the form on the Main method and then do an explicit dispose, after the run call.

MyFormClass theForm = new MyFormClass();
SingleApplication.Run(theForm);
theForm.Dispose();

Is there any design reason to prefer one over the other?

http://www.codeproject.com/csharp/singleinstance.asp

Re: Proper way to handle single instance application and multithreading

ejuanpp25-Oct-06 4:23

ejuanpp

25-Oct-06 4:23

why don't you do your test by using a mutex before Application.Run ?

Re: Proper way to handle single instance application and multithreading

Dan Neely25-Oct-06 4:56

Dan Neely

25-Oct-06 4:56

The wrapper class I'm using to prevent multiple instances does do that. In order to remain a generic implementation that can just be dropped into additional apps however, it can't have any specific knowlege of what form it's creating. This means that the form has to be passed to the class that does the check and then launches the app, which in turn means that the constructor has to be called before making the check.

Just want to init a member of a struct

qingyingqy25-Oct-06 2:34

qingyingqy

25-Oct-06 2:34

I declare a struct like this :
struct dataSeg
{
char[] QN;
char[] PNUM;
StringBuilder CP;
}
I want to init the member such as QN,PNUM,CP
How can I init the QN.......?
My meaning is:when I declare a variable of dataSeg ,I want QN, the member of the variable,can be alloc 20 bytes?
How can I get the result?

Re: Just want to init a member of a struct

User 665825-Oct-06 3:13

User 6658

25-Oct-06 3:13

Use a class and do that:

char[] QN = new char[20];

Struct don't allow field initializers.

regards

modified 12-Sep-18 21:01pm.

Re: Just want to init a member of a struct

Guffa25-Oct-06 3:15

Guffa

25-Oct-06 3:15

I would strongly advice you to make a class instead of a struct, as the data that you store in it are objects.

In the constructor you can create the objects. Example:

public dataSeg() {
   this.QN = new char[20];
   this.PNUM = new char[42];
   this.CP = new StringBuilder();
}

I assume that you wanted the QN to be 20 characters, not 20 bytes, as 20 bytes would be 10 characters.

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

ComboBox and DataSource attribute

zaboboa25-Oct-06 2:33

zaboboa

25-Oct-06 2:33

Hello,

I have a few comboboxes on the form. They all have the same datasource, the only thing I want to implement is if one of the comboboxes has a value selected, it will be filtered out from the other comboboxes, meaning you can't select the same value in two, or more comboboxes, it can only appear in one combobox. Is there a way to do it?

Thank you.

Re: ComboBox and DataSource attribute

sam#25-Oct-06 7:47

sam#

25-Oct-06 7:47

i didn't find any direct method for it but you can achieve desired behaviour by making copy of datasource and filter datasource when selected value of a combobox get change.

sameer

Disable Ambient properties from being set

chricla25-Oct-06 2:23

chricla

25-Oct-06 2:23

Some controls have properties that are ambient, which makes them set as the controls parent/container. Does anyone know how this can be avoided? I have found this to be connected to the Site-property in controls, but cannot see how I am to go about it if it's at all possible.

Any hints?

All needed for evil to prevale is for good men to do nothing.

C Smile | :)

Re: Disable Ambient properties from being set

sam#25-Oct-06 8:04

sam#

25-Oct-06 8:04

if you want to display a control so you have to embedded it some where.so parent child relationship get genrated automatically.so you cant avoid it.to access added control you can use container.Controls

sameer

Application hang-up in .net 2.0 windows forms

pranu_1325-Oct-06 1:11

pranu_13

25-Oct-06 1:11

Hi all,

i have a peculiar problem in closing the windows forms.

In order to work with multiple instances of same form asynchronously,i am invoking the method using the beginInvoke method of a delegate as follows:

testDelegate del = new testDelegate(SubmitData);
del.BeginInvoke(null, new object[] { });

Its working fine . But when i close these instances, application is getting hanged.

In close button i just wrote this.close() method.

This application is a .net 2.0 windows application.

Can any one help me out to solve this please...

Thanks,
Pranu.

Re: Application hang-up in .net 2.0 windows forms

Judah Gabriel Himango25-Oct-06 5:10

Judah Gabriel Himango

25-Oct-06 5:10

We'd need more code to help you out. SubmitData, what does that function look like? If your app hangs on close, can you pause execution under a debugger and see what it's trying to execute?

Another possibility: each thread, apart from the main UI thread, should have its Thread.IsBackground property set to true. Otherwise, your app will stay alive while those threads are running.

Tech, life, family, faith: Give me a visit.
I'm currently blogging about: God-as-Judge, God-as-Forgiver
The apostle Paul, modernly speaking: Epistles of Paul

Judah Himango

Need to access string from HTMLRequest

jarlath25-Oct-06 1:08

jarlath

25-Oct-06 1:08

I have the following output from a webBrowser scrape and need to estract the XML section using C#;

</td>
</tr>
</table-->
<itemData><userID>-99999</userID>
<introducerID>-99999</introducerID>
<branchID>-99999</branchID>
<softwareID>-99999</softwareID>
<errorID>1</errorID>
<errorDesc>The branch Id supplied does not correspond with a branch in the system.</errorDesc>
</itemData>
<style>
table.cfdump_wddx,
table.cfdump_xml,

Im currently using string contentText = response.Substring(response.IndexOf("<itemData>")+0,218); as a means of getting the start but cannot get the end of the string and end up getting into the style tag.

Can anyone help??

Re: Need to access string from HTMLRequest

J. Dunlap25-Oct-06 1:44

J. Dunlap

25-Oct-06 1:44

Regular expressions work well for that:

Match match = Regex.Match(strHtml, @".*(?<XML>\<itemData\>.*?\</itemData\> ).*", 
		RegexOptions.Singleline | RegexOptions.IgnorePatternWhiteSpace);
string xmlFragment = match.Groups["XML"].Captures[0].Value;

Re: Need to access string from HTMLRequest

jarlath25-Oct-06 4:58

jarlath

25-Oct-06 4:58

Tried this but im getting an error on the IgnorePatternWhiteSpace;

C:\projects\projectGreen\WindowsApplication2\Form1.cs(67): 'System.Text.RegularExpressions.RegexOptions' does not contain a definition for 'IgnorePatternWhiteSpace'

Tried to solve to no avail

Re: Need to access string from HTMLRequest

Elina Blank25-Oct-06 6:23

Elina Blank

25-Oct-06 6:23

It is IgnorePatternWhitespace
Not IgnorePatternWhiteSpace

Sincerely,
Elina

Life is great!!!
Enjoy every moment of it! Blush | :O

about tokens

keluo25-Oct-06 0:55

keluo

25-Oct-06 0:55

How to make the scanning step in the compiler ?

Re: about tokens

Judah Gabriel Himango25-Oct-06 5:11

Judah Gabriel Himango

25-Oct-06 5:11

Could you clarify what you mean? Are you trying to induce the compiler to perform a code scan, or are you trying to compile C# code yourself?

Tech, life, family, faith: Give me a visit.
I'm currently blogging about: God-as-Judge, God-as-Forgiver
The apostle Paul, modernly speaking: Epistles of Paul

Judah Himango

How to check all the check boxes in a listview from the start.

Support12325-Oct-06 0:34

Support123

25-Oct-06 0:34

Hi all,

I have added some items to a listview that has checkboxes, in the form's load method.

ListViewItem _selectionitem;<br />
_selectionitem = listboxSelect_List.Items.Add("ITEM A");<br />
_selectionitem = listboxSelect_List.Items.Add("ITEM B");<br />
_selectionitem = listboxSelect_List.Items.Add("ITEM C");<br />
_selectionitem = listboxSelect_List.Items.Add("ITEM D");<br />
_selectionitem = listboxSelect_List.Items.Add("ITEM E");<br />
_selectionitem = listboxSelect_List.Items.Add("ITEM F");<br />
_selectionitem = listboxSelect_List.Items.Add("ITEM G");<br />
_selectionitem = listboxSelect_List.Items.Add("ITEM H");<br />
_selectionitem = listboxSelect_List.Items.Add("ITEM I");<br />
_selectionitem = listboxSelect_List.Items.Add("ITEM J");<br />
_selectionitem = listboxSelect_List.Items.Add("ITEM K");<br />
_selectionitem = listboxSelect_List.Items.Add("ITEM L");<br />
_selectionitem = listboxSelect_List.Items.Add("ITEM M");<br />
_selectionitem = listboxSelect_List.Items.Add("ITEM N");

I want to make all the checkboxes in the listview be checked but can't seem to get it right... i've been struggling for a while now.

If anyone knows how please let me know.

Thank you. (I'll keep trying and let you know if i get it right first)

"Many of life's failures are people who did not realize how close they were to success when they gave up." Thomas A. Edison

Re: How to check all the check boxes in a listview from the start.

snorkie25-Oct-06 2:25

snorkie

25-Oct-06 2:25

foreach (ListViewItem lstItem in _selectionitem)
{
lstItem.Checked = true;
}

Hogan

Re: How to check all the check boxes in a listview from the start.

Shy Agam25-Oct-06 2:31

Shy Agam

25-Oct-06 2:31

Hey NarutoFan#1,

You can use the Checked property of the ListViewItem class, and set it to true after each item addition:

_selectioitem = listboxSelect_List.Items.Add("ITEM A");
_selectionitem.Checked = true;

or:

listboxSelect_List.Items.Add("ITEM A").Checked = true;

Alternatively, you can use a foreach loop after adding all of the items:

.
.
.
_selectionitem = listboxSelect_List.Items.Add("ITEM N");

foreach (ListViewItem item in listboxSelect_List.Items)
    item.Checked = true;

Best Regards,
Shy.

PS
Naruto rocks! :P

Re: How to check all the check boxes in a listview from the start.

Support12325-Oct-06 2:39

Support123

25-Oct-06 2:39

Thank you. I appreciate the help.

Glad to see another Naruto fan...
I hope you enjoy "BLEACH" aswell... Great anime.

Enjoy the rest of your day.

Thanks once again. Wink | ;)

"Many of life's failures are people who did not realize how close they were to success when they gave up." Thomas A. Edison

Changing windows service account

kulile25-Oct-06 0:32

kulile

25-Oct-06 0:32

Good day

I am trying to write an application that will change a windows account details. If the account is running under the Local System Account, I can change it though my application so that it impersonate user particular user.

The problem now is that I'm battling to change a windows service so that it runs under Local System and not under an impersonated account - if it was already running under an impersonated account. Can anyone please help me with this.

Thanx in advance

Kulile --- RSA

drive formating for USB Stick (2nd try)

Martin#25-Oct-06 0:15

Martin#

25-Oct-06 0:15

Hello,

I have a Windows Application with .Net 1.1.
Problem is that I have to format (compl erase) the drive, like Windows Explorer does it.

Hope someone can help me, please.

Thanks in advance,

Martin

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