Re: Screen Saver Enabling/Disabling - C# Discussion Boards

RoyceF22-Mar-05 6:45

22-Mar-05 6:45

Hi,

I have a viewer that uses multiple TabPages to view groups of rectangular objects. I want to enable the user to drag an object from one tab page to another tab page. If the left mouse button is NOT down, the Tabcontrol's MouseMove, MouseEnter, & MouseHover handlers are called. However, once the left mouse button is down for the drag, these handlers are never called. How do I implement simple drag & drop between tab pages? The problem is I can't activate the target tabpage if the TabControl's or the TabPage's handlers are not called when the mouse rolls over the tab.

Any help appreciated,
Royce

Re: Drag object between tab pages

Nick Parker22-Mar-05 16:50

Nick Parker

22-Mar-05 16:50

There are several articles here covering drag and drop, here[^] is one specifically.

- Nick Parker
Microsoft MVP - Visual C#
My Blog | My Articles

regular expressions exclusion and alternation

Anonymous22-Mar-05 4:51

Anonymous

22-Mar-05 4:51

hi guys i want to strip ceartin information from between tags but they differ in some things:

1:
<a.*?>(strip this 1)</a>

2:
(strip this 2)

3:

<a.*?>(strip this 3)</a>

Using the same regex object(i.e one expression for all 3), it got to be....

i've tried this expression but dosn't work?!

(<a.*>()?)?(.*)(()?</a>)?

please can any one help

regards

DTS FLAT File

vchalla22-Mar-05 4:23

vchalla

22-Mar-05 4:23

Hi all,

How to use DTS Flat file provider for reading a text file data and fill dataset.I know how to get using OleDB providers.But i do not how to use DTS Flat file to read a text file using delimiters and fill the dataset.

If body have any idea please reply back.

thanks in advance.

Sastry.

sastry ch

Re: DTS FLAT File

Joshua Lunsford22-Mar-05 11:40

Joshua Lunsford

22-Mar-05 11:40

DTS in its simplest form will convert your flat file using the delimiters, into fields of a table. When creating a DTS package it has a handy wizard that will walk you through matching up fields(simular to a excel import process) Then go into your c# form and make a connection to that database where that table is located and select what you want and adapter.fill(dataset) kinda thingy.

-Joshua Lunsford

User selected color dropout

montu337722-Mar-05 4:21

montu3377

22-Mar-05 4:21

Hi,

As per our project requirement ,i want to dropout color as per user selected color like suppose user draw one rectangle one image & then press "dropout this color" then my function should be capable to dropout that user selected color.
Tell me is my below approach is right or wrong or required some more improvement.

I am thinking that when user draw one rectangle on some part of the image,get the Average of R,avg. of B,Avg. of G value and now i have to dropout the value which i got user selected in avg. R,Avg.B and Avg. G, so again i do the grey scale of the image and then do the contrast of the image.

so can anybody tell me is that approach is right or i need some more change.If any change is that which types of change i had to do?

montu3377

Screen Saver Enabling/Disabling

B D Richardson22-Mar-05 4:21

B D Richardson

22-Mar-05 4:21

Does anyone know if there is a problem with re-enabling the Screen Saver after it has been disabled programmatically.

I am using the SystemParametersInfo function within User32.dll, and have been successful in disabling the Screen Saver, but it does not work for re-enabling. The only way I can re-activate it is to re-apply the settings through the Display properties in the Control Panel.

Sample lines of code, in simplest form:

// Screen Saver disable<br />
SystemParametersInfo( 17, 0, 0, 0);<br />
<br />
// Screen Saver enable<br />
SystemParametersInfo( 17, 1, 0, 0);

I have discovered there may be problems with retrieving the Active status, but have not found any information relating to re-activation.

Your assistance would be much appreciated.

Re: Screen Saver Enabling/Disabling

Heath Stewart22-Mar-05 5:47

Heath Stewart

22-Mar-05 5:47

I would first suggest you don't use magic numbers like 17, but instead define them as constants (typically using the same name as their native equivalent):

const int SPI_SETSCREENSAVEACTIVE = 0x0011; // 17
const int SPIF_UPDATEINIFILE = 0x01; // 1
const int SPIF_SENDCHANGE = 0x02; // 2

You should also consider setting the last parameter to SPIF_UPDATEINIFILE | SPIF_SENDCHANGE to make sure the setting is persisted and to make sure that other apps are notified if the screensaver is disabled, even if temporary (apps that handle the message may react in certain ways as required by their functionality). What could possibly be the problem is that Windows doesn't realize the screensaver has been disabled (at least some component of it). I've always send SPIF_SENDCHANGE at the very least and have never run into this problem.

This posting is provided "AS IS" with no warranties, and confers no rights.

Software Design Engineer
Developer Division Sustained Engineering
Microsoft

[My Articles] [My Blog]

Re: Screen Saver Enabling/Disabling

B D Richardson22-Mar-05 22:13

B D Richardson

22-Mar-05 22:13

Many thanks for your very constructive and prompt advice.

The error of my ways was that in my actual coding, I had overlooked the order of the parameters. I was infact foolishly changing the value for the incorrect parameter.

I do agree with defining constants. I had only used 'magic numbers' in the example for simplicity. Which is why I had stated the code as in its simplest form.

Once again, thanks for your assistance.

Re: Screen Saver Enabling/Disabling

B D Richardson23-Mar-05 1:39

B D Richardson

23-Mar-05 1:39

I believe that would seem to be a problem with using Int64 data types for the parameters. This only fails when re-activate the screen saver though. And does not seem to be a problem for making the screen saver inactive.

Using Int32 works just fine.

Re: Screen Saver Enabling/Disabling

Heath Stewart23-Mar-05 12:43

Heath Stewart

23-Mar-05 12:43

You shouldn't use Int64 anywhere, and I'm not sure you didn't get that. A DWORD is always an unsigned int (32-bits), but the third parameter - an LPVOID - should actually be declared as an IntPtr, which is 32 bits on a 32-bit OS and 64 bits on a 64-bit OS (unless running under WOW64).

This posting is provided "AS IS" with no warranties, and confers no rights.

Software Design Engineer
Developer Division Sustained Engineering
Microsoft

[My Articles] [My Blog]

Working with DNS class

vad_kr22-Mar-05 3:39

vad_kr

22-Mar-05 3:39

Hi everybody...

I was discovering System.NET.DNS class and found 2 useful functions for every NET programmer. They are: GetHostByAddress and GetHostByName. Description says that DNS server will resolve the argument and return IPHostEntry class.
I'm developing an application that will be installed on the network without DNS.
So, the question is: Does this class works with DNS server only or able to read hosts.csv file as well and able to resolve some hosts using the information from the file.
Thanx

Vad

Re: Working with DNS class

leppie22-Mar-05 4:13

leppie

22-Mar-05 4:13

You can use GetHostByName(NETBIOSNAME), that works too, and to get the NETBIOSNAME i think its Environment.MachineName.

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

Re: Working with DNS class

stinGfasT22-Mar-05 9:06

stinGfasT

22-Mar-05 9:06

hi I don't know C#

Re: Working with DNS class

Anonymous22-Mar-05 9:25

Anonymous

22-Mar-05 9:25

And this means what to us?

Searching DataSets with multiple strings

Joshua Lunsford22-Mar-05 3:27

Joshua Lunsford

22-Mar-05 3:27

This is what i'm trying and it is not working... any clues?

<br />
SqlDataAdapter adp = new SqlDataAdapter(myCommand);<br />
DataSet ds = new DataSet();<br />
adp.Fill(ds);<br />
ds.Tables[0].Select("COLUMN1 LIKE '*" + string1 + "*', COLUMN2 LIKE '*" + string2 + "*', COLUMN3 LIKE '*" + string3 + "*'");<br />
MyRepeater.DataSource=ds.Tables[0].DefaultView;<br />
MyRepeater.DataBind();<br />

System.NullReferenceException occurred in Unknown Module

AO-Action22-Mar-05 1:36

AO-Action

22-Mar-05 1:36

Hi every body... I'v searched the comments, I did find pieces of information here and there but it's not even near the bull's-eye, so I decided to post a new thread hopping for someone to help me getting out of this problem Smile | :)

the main/parent form is an MDI form and the child is a normal form. The problem accurres after the user selects the child from parent's mainmenu, during the process of loding the child form I get this message
http://mars.walagata.com/w/action/DotNet/unhand.jpg[^]
"An unhandled exception of type 'System.NullReferenceException' occurred in Unknown Module. Additional information: Object reference is not set to an instance of an object."

and after I clicked the continue, the child form runs without any prob. butif I clicked the Break this messagebox shows up
http://mars.walagata.com/w/action/DotNet/there-is.jpg[^]

this is part of the code related to the problem (I think)
the parent part... calling the child

AccountEdit editAccount = new AccountEdit();<br />
editAccount.MdiParent = this;<br />
editAccount.Show();

I removed the "MdiParent = ..." and its the same, changed the Show() to ShowDialog() and still the same

the chiled part..
I DIDN'T CODE ANY THING, I just draged and droped controls and rearrange them on the form. The one thing I remember is that this problem started to showup after I add any list control and this time I added ListView control.
Here is a link to the code (I don't want to make this message long) :
http://mars.walagata.com/w/action/DotNet/code.txt[^]

after reading some posts that said that this only accurres in the VS.net 2003 environment, I decided to ignore this exception http://mars.walagata.com/w/action/DotNet/exception.jpg[^]
some other posts said that uninstalling and reinstalling the framework will solve the prob but I don't believe so

It is related to referencing null value only after the Show(), so any ideas?

and another question, why after some time I can't type '{' in vs.net?

Re: System.NullReferenceException occurred in Unknown Module

Robert Rohde22-Mar-05 2:05

Robert Rohde

22-Mar-05 2:05

Sounds really strange...

I would do the following: Surround your ShowDialog call with a try catch block and look at the stack of the exception (and post it here). This will hopefully give further hints.

<br />
try {<br />
editAccount.Show();<br />
} catch (Exception exc) {<br />
Console.WriteLine(exc.StackTrace);<br />
}<br />

Re: System.NullReferenceException occurred in Unknown Module

AO-Action22-Mar-05 2:31

AO-Action

22-Mar-05 2:31

Thanks alot Rohde for your reply,
I did and the same message still comming

hopefully that the framework 1.1 SP1 will solve this problem, Microsoft mentioned some NullReferenceException errors were fixed in this SP, I hope I didn't install this fix before but anyway assume that the problem remains even after I installed the SP, any ideas?

and if this fix did the job I'll report back Smile | :)

How to get text on screen

levgiang22-Mar-05 0:39

levgiang

22-Mar-05 0:39

How can i write a program can get text at current mouse position

le van giang

Re: How to get text on screen

leppie22-Mar-05 1:07

leppie

22-Mar-05 1:07

With great difficulty. The only way to do it generically is to do OCR.

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

Re: How to get text on screen

Dave Kreskowiak22-Mar-05 4:48

Dave Kreskowiak

22-Mar-05 4:48

And I think I've told you this before...

And leppie's comment "with great difficulty" is an understatement!

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

list view goes blank

maheshfour21-Mar-05 23:12

maheshfour

21-Mar-05 23:12

hi all,

I am facing with an unusual problem. i am doing a project involving TCP/IP packet capturing. I display the packets in a list view. it works most of the times except the first time.

For the first time when i click start button the list view goes blank. after that it works properly.

can any one help me?

Re: list view goes blank

Dave Kreskowiak22-Mar-05 4:45

Dave Kreskowiak

22-Mar-05 4:45

That depends entirely on how your filling the ListView while your capturing packets. Are you letting the ListView update itself after filling it with data? Is your packet capture process running on the same thread of the UI? If so, then you're going to have to call Application.DoEvents to let the Window and it's controls redraw themselves. A better method would be to run the capture process on a seperate thread and have it post calls back to the Window with the ListView telling it to add the data, possibly using an event.

Also, consider that you can't possibly update the ListView fast enough to post every packet that flies by as it does so. You might want to hold off updating the ListView until the capture is finished, then you can populate the ListView however you want.

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

tabs in tree view

Anonymous21-Mar-05 23:05

Anonymous

21-Mar-05 23:05

hi friends,

how can i indent the data ( nodes ) in a tree view using tab. I tried using "\t" in the node string, but it displays a square character in the node instead of indenting.

mahesh

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