C# Discussion Boards - CodeProject

Re: Rectangle selection control

9-Apr-03 20:00

Is there some control or DLL that facilitates rectange selection, as found on the Windows Desktop and many paint/presentation programs? Ideally it would help select child controls.

Or is this something that must be coded from scratch on a custom basis?

For instance, let's pretend that I wanted to simulate the Windows Desktop and wanted to be able to select icons by dragging a mouse to form a rectangle selection. Without any special DLL help, I would have to manage the drawing of the rectangle via mouse events, check for controls within the rectangle's area, and select the controls, perhaps by highlighting them in some way. Or I could also change the selections list by clicking on controls with the Control key.

Smitha Nishant9-Apr-03 20:09

Smitha Nishant

9-Apr-03 20:09

Try ControlPaint.DrawReversibleFrame Method.

Regards
Smitha

It is better to be hated for what you are than to be loved for what you are not.
-- Andre Gide

Re: Rectangle selection control

Arun Bhalla9-Apr-03 20:13

9-Apr-03 20:13

Yeah, that's definitely part of what I'd need to do if I have to do it from scratch.

I was hoping since this seems to be a common enough task for applications that there would be more OS or Framework support for it.

XmlTextWriter query

Nish Nishant9-Apr-03 17:00

Nish Nishant

9-Apr-03 17:00

Guys

can we use the XmlTextWriter class to open an existing xml file and add some stuff to it? or is it only for creating fresh xml files?

Nish

p.s. if you cant, then how do you add some stuff to an existing xml file?

Author of the romantic comedy

Summer Love and Some more Cricket [New Win]

Review by Shog⁹
Click here for review[NW]

Arun Bhalla9-Apr-03 19:14

9-Apr-03 19:14

XmlTextWriter writes forward-only streams. You should use XmlDocument if you want to manipulate the XML file.

XmlTextWriter would probably work okay if you just wanted to append to the end of the XML file, but XmlDocument will save you the trouble of having to worry about the formatting on a low level.

Nish Nishant9-Apr-03 20:00

Nish Nishant

9-Apr-03 20:00

Thanks Arun. I will look up XmlDocument

BTW XmlTextWriter will overwrite the file Frown | :-(

So even appending is not possible.

Nish

Author of the romantic comedy

Summer Love and Some more Cricket [New Win]

Review by Shog⁹
Click here for review[NW]

Arun Bhalla9-Apr-03 20:02

9-Apr-03 20:02

Nishant S wrote:
BTW XmlTextWriter will overwrite the file So even appending is not possible.

I wonder if that's true, if you get the XmlTextWriter's underlying stream and seek to a certain position in the file. I was able to do that when using an XmlTextWriter with a MemoryStream.

Question about multiple threads

Nish Nishant9-Apr-03 20:05

Nish Nishant

9-Apr-03 20:05

Arun Bhalla wrote:
I wonder if that's true, if you get the XmlTextWriter's underlying stream and seek to a certain position in the file. I was able to do that when using an XmlTextWriter with a MemoryStream.

Ah okay, that's an idea. But it'd still be sorta impossible or at least very difficult to write proper xml I guess. I'll look up XmlDocument as you had suggested.

Nish

Author of the romantic comedy

Summer Love and Some more Cricket [New Win]

Review by Shog⁹
Click here for review[NW]

macros in C#

TigerNinja_9-Apr-03 14:55

TigerNinja_

9-Apr-03 14:55

can you write macros in c# ? if so how to begin ? can you reference a link or example plz.

tia

R.Bischoff | C++

.NET, Kommst du mit?

Re: macros in C#

TigerNinja_10-Apr-03 2:53

TigerNinja_

10-Apr-03 2:53

Yes you can, however, the ms docs have tons of examples all in VB.NET Frown | :(

I am going towards writing an add-in instead. The add-in wizard get's you started.

R.Bischoff | C++

.NET, Kommst du mit?

Johan de Koning9-Apr-03 10:40

Johan de Koning

9-Apr-03 10:40

I have the following situtation

In my program i want to do request an dns lookup for several servers. How many servers are variable and are listed in a string array. Now i want to request the dns lookup not after each other but i want to do them in threads. So that not one dns lookup is waiting before the other is ready.

From each dns lookup thread i want the IPaddress as return value. And after all i want my program to continue after all threads are stopt.

So a quick summary

- Program start
- List of servers is in array list (for example 10)
- Starts 10 threads with the server to check as parameter
- Get response of the threads (and keep them in memory)
- Continue with program after all threads are done

I hope someone can help me with this. I search a lot about Threads but havend found a clear solutions for this problem. And if you think you had an other/better solution without threads, please reply also.

Thanx

Re: Question about multiple threads

TigerNinja_9-Apr-03 13:53

TigerNinja_

9-Apr-03 13:53

If your using threads I highly recommend using the ThreadPool class. Caution, there is an error with the ThreadPool with WebRequests, but I am not sure if it applies to Dns class.

R.Bischoff | C++

.NET, Kommst du mit?

Key mappings

CP039-Apr-03 9:26

CP03

9-Apr-03 9:26

Can I map key combinations (like Alt-2) to form methods in C#.

I should mention, Windows Forms apps...

Database filtering quandries

RB@Emphasys9-Apr-03 9:07

RB@Emphasys

9-Apr-03 9:07

Hello people,

I have a quick question for you. I am currently importing data into an access database and i need to check each field and make sure that it does not exceed the maximum lenth of the fields in our database. So.... I create a DataSet, the a DataTable, and then use the column collection to try and find the max length of the field, something like this:

oDataTable.Columns[k].MaxLength

All I ever seem to get is a -1 for the maxlength, although all the other data shows up great. I was wondering if anyone had a suggestion as to what Im doing wrong.

Thanks so much!
Ryan

C# Equiv to WITH in VB.NET

Dato9-Apr-03 6:57

Dato

9-Apr-03 6:57

I was wondering if there is a C# equivalent to the 'with' stmt in vb.net ..
I have some code that sure needs it!
thks in advance .

Daniel Turini9-Apr-03 7:09

Daniel Turini

9-Apr-03 7:09

Dato wrote:
I was wondering if there is a C# equivalent to the 'with' stmt in vb.net ..
No, there isn't, and some people think that there should not be, I'll explain why below.

Dato wrote:
I have some code that sure needs it!
So, put this code in a method in this object.

It's not the fall that kills you: it's the sudden stop - Down by Law, Jim Jamursch (1986)

J. Dunlap9-Apr-03 8:31

J. Dunlap

9-Apr-03 8:31

I came up against this problem, too, and no, you can't always put the code in a method of the object. I don't see any reason not to have a with block statement, except that C++ didn't have one, which is a very poor excuse!

"Do unto others as you would have them do unto you." - Jesus

"An eye for an eye only makes the whole world blind." - Mahatma Gandhi

Roger Alsing10-Apr-03 3:13

Roger Alsing

10-Apr-03 3:13

so what is the problem?
if you are going to set props on a something down a hirarchy like:

MyBlah.SomeBluh.LastWow.Gnu.BackColor=color.red;<br />
MyBlah.SomeBluh.LastWow.Gnu.ForeColor=color.green;<br />
MyBlah.SomeBluh.LastWow.Gnu.Text="hello you!"

it would be very simple to just make a temp holder for gnu:

GnuType g=MyBlah.SomeBluh.LastWow.Gnu;<br />
g.BackColor=color.red;<br />
g.ForeColor=color.green;<br />
g.Text="hello you!"

that would do the exact same thing . ok . you would have to type "g" infront of every prop , but thats about it...

//Roger

Member 26118811-Apr-03 1:14

Member 261188

11-Apr-03 1:14

I think that using a temporary holder (many times) floods the memory untill the garbage collector comes. And how would you release the resources used by g?