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I have a simple question, but i don't know how to do it.
I have a collection of data, and would like to query it using LINQ. Then, i want to modify the resultant collection, which updates the original collection
For example
i have the following collection
int[] data = { 0, 1, 2, 3, 4, 5 };
I want to select all data larger than 3 (thus 4 and 5), and then modify them by multiplying them with 10.
My final collection should look like this. (This is a simple example, in reality, i will be using a complex object)
data = {0, 1, 2, 3, 40 , 50};
I tried this; but doesn't update the original collection. Does ToList() return a copy of the collection?
How do i go about doing this?
int[] data = { 0, 1, 2, 3, 4, 5 };
var a = from n in data
where n > 3
select n;
List<int> b = a.ToList();
for (int i = 0; i < b.Count(); i++)
{
b[i] = 10*b[i];
Console.WriteLine(b[i]);
}
for (int i = 0; i < data.Count(); i++)
Console.WriteLine(data[i]);
Data still contains 0,1,2,3,4,5 instead of 0,1,2,3,40,50,which is what i want.
Please help, many thanks.
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LINQ is not designed for that sort of thing. LINQ is designed to be "functional" in that it aims to provide methods that do not affect the state from which they are queried.
You will need to do a for loop yourself to do this.
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On top of what Gideon said, you don't have any code that modified the array at all. You mode changes to your "b" list (which is a seperate object from the "data" array), but then you displayed the original data list.
Oh, and BTW. Array's in .NET are immutable. You cannot change the size of an array once it's created.
Your LINQ query returned a List object containing 2 integers, 4 and 5. It does NOT return the source array you are querying. Then you multiplied the two integers in that List by 10 and over-wrote the values in the List with the new values. You didn't touch the original Array of numbers at all, but then you displayed them.
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Thanks, now i understand.
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I need an open source C# program that can receive SMTP messages (sends "250 OK" etc.) and save them in MailMessage (and sends messages, but this is optional since I found a lot of those..)
What protocol does it use? POP3 or SMTP?
thanks in advance 
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This article, A POP3 Client in C# .NET[^], looks like what you want; not too far away either.
txtspeak is the realm of 9 year old children, not developers. Christian Graus
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From a client point of view:
POP3 and IMAP are the main protocols for receiving email.
SMTP is for sending email.
Dave
Binging is like googling, it just feels dirtier. (Pete O'Hanlon)
BTW, in software, hope and pray is not a viable strategy. (Luc Pattyn)
Why are you using VB6? Do you hate yourself? (Christian Graus)
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I am working on a school project which calls for a random number based on user input and unfortunately I cannot seem to find how to do this. My book does not offer a very good explanation of this and when I search for this online I get some very confusing results. Here is the problem in a nutshell:
I am creating a math game to be used by children. They need to provide which operator they want and choose the maximum numbers to use when generating the problems.
My random generator needs to be based on what the maximum numbers are. For example:
User input:
maxNumber1: 5
maxNumber2: 10
random generated problem:
5+10 (or any other problem using 1-5 and 1-10)
I am not asking for anyone to solve my problem for me but I would appreciate a little direction as to where I can find the answer that would pertain to this scenario.
Thanks in advance!
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Without negative values? I guess you should look at Random.Next(int)[^]
Don't forget to only create 1 instance of Random, don't make a new one every time (ok I know it's not like it will really matter in this case, but it's still bad practice to do it)
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For instance:
Random RandomClass = new Random();
// The Next method should be called with two arguments: the minimum value and the maximum value.
int RandomNumber = RandomClass.Next(maxNumber+1, maxNumber+2);
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Dear all,
I have some ComboBox column in DataGridView. In order to user-friendly, when user focus in ComboBoxCell they drop down automatically
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Neat! How'd you do it? 
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please tell me that how change buttons messagebox
i want have buttons with other caption in messagebox
please insert source code to c#.net 2005.
my mail is : simon.thirteen@gmail.com
modified on Wednesday, March 24, 2010 12:33 PM
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Amin shamooni wrote: please insert source code to c#.net 2005
Code requests are not entertained here.
Look at the constructors of the MessageBox class. It has few options. If that does not suites, create your own.
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The MessageBox is a build in Windows dialogue, not even really .net. You can't change the button text, though there are many combinations of buttons you can show.
You will have to replicate it with your own Form and then you have total control over the buttons.
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CodeProject is a beautiful website. It has many features. One of the most important features is "SEARCH".
A simple search for message box could easily have given you some suggestions for your answer.
Amin shamooni wrote: please insert source code to c#.net 2005
Noone is going to give you a source code. If you show some proof that you have done some work, people here will help you.
In any case, have a look at this Article on CodeProject: XMessageBox - A reverse-engineered MessageBox()[^]
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my mail is :simon.thirteen@gmail.com
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I am having an issue with a Fax component. It works when installed on a WinXP machine, but has an exception on Server 2003.
Here is my exception:
The COM class factory for component with CLSID {D73733C8-CC80-11D0-B225-00C04FB6C2F5} failed due to the following error: 80040154.
I found a couple of articles stating that this is a problem seen in 64-bit operating systems. I have personally confirmed that neither system is 64-bit, yet the problem persists (no exception in XP, exception in server 2003).
This is my first time using FAXCOMLib, so if I am making some rookie mistake please let me know. Thank you!
Here is the section of code that is failing:
FAXCOMLib.FaxServer faxServer = new FAXCOMLib.FaxServerClass();
faxServer.Connect(Environment.MachineName);
FAXCOMLib.FaxDoc faxDoc = (FAXCOMLib.FaxDoc)faxServer.CreateDocument(file.FullName);
faxDoc.RecipientName = recipientName;
faxDoc.FaxNumber = faxNumber;
faxDoc.DisplayName = displayName;
faxDoc.Send();
faxServer.Disconnect();
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It should be easy to fix it:
It means that your module is not registered, so you have certainly copied the library to your target system without registring it.
* regsvr32 xxxx.dll if you have an error use a tool to check if a missing dependency is not missing (dependency [^]
Keep update us.
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OK, the COM problem is fixed - the Windows Fax service was not configured on the account the prog is using. (Apparently Windows fax must be configured for each account?)
However, a different exception is being thrown by the same code block:
Access is denied. (Exception from HRESULT: 0x8007005 (E_ACCESSDENIED))
So apparently, it has permissions issues in reaching the Fax service...
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The difference maybe in UAC control which may prevent to load the DLL or to access a specific resource.
Look at this policy explainations for more details:
http://www.15seconds.com/Issue/040121.htm[^]
Because, remotely it will be difficult to find any potential security reasons. Depending on the installation and the way you have installed your software. 
Good luck. Keep us updated.
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Hi,
I created setup and deployment to my project and would like to provide license agreement for the installation. Please guide me. Thanks in advance
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There is a License agreement dialog which can be added to the set up project. Try that.
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Hei,
Is there any option to change the rows color of datagrid on some condition,
like i wan to change the alternate color of the dg like this
conditionalcolumn color
1 Blue
1 Blue
2 white
3 blue
4 Blue
5 Blue
6 Blue
7 Blue
8 Blue
9 Wite
Thanks
Syed Shahid Hussain
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