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With the help of a workmate, I've resolved the issue. The quirk was in the Add method of the DataColumnCollection class (which holds the cells for the rows). The writers of the method, in their infinite wisdom, convert the input value to a string before adding it. This is default behaviour. It can be overridden by creating a custom DataColumn to hold the type of the input data. I'm including the code which now works.
using System;<br />
using System.Data;<br />
using System.Collections;<br />
class CastTest {<br />
const string COL = "test";<br />
static void Main() {<br />
Console.WriteLine("CastTest");<br />
ArrayList list = new ArrayList();<br />
string str = "Hello world";<br />
list.Add(str); <br />
Console.WriteLine("arrayList created"); <br />
DataTable table = new DataTable();<br />
DataColumn dC = new DataColumn(COL, list.GetType());<br />
table.Columns.Add(dC);<br />
DataRow row = table.NewRow();<br />
table.Rows.Add(row);<br />
row[COL] = list;<br />
Console.WriteLine("table created"); <br />
object resultObj = table.Rows[0][COL]; <br />
Console.WriteLine("resultObj type: " + resultObj.GetType()); <br />
ArrayList resultList = (ArrayList) resultObj; <br />
string resultStr = (string)resultList[0];<br />
Console.WriteLine(resultStr);<br />
}<br />
}
I guess I should be reading the documentation more closely so that I would be more aware of "features" like this 
Thanks for the replies. Regards,
Michael
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Can somebody tell me how to escape the semicolan character in C#.
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Use the @ character before the opening double-quote of a string, such as:
string myName = @"My name is ; Ashok Dhamija";
label1.Text = myName;
This will correctly show the string alongwith the semi-colon character. Once you use the @ character as above, there is no need to further add any escape characters in the string.
Edited on 25 April:
The @ character will obviate the need for using the escape character while defining a string with any sort of characters used in it (whatsoever, whether otherwise requiring an escape character or not)including semi-colon (though a semi-colon does not require an escape character as pointed out by leppie in the next message)
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Connection.close and Connection.dispose, which one is better?
Can someone tell me which one should I use?
Thanks in advance.
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Assume nothing. If you want to close it, close it. If you want to dispose of it, close it and then dispose it. Better yet, the using keyword will dispose of it for you.
Christian Graus - Microsoft MVP - C++
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Neither. The methods are used for different purposes entirely.
Calling .Close() will close the connection, but leave the object available so it can be reopened.
Calling .Dispose() will close the connection and destory the object, tagging it for GC.
RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome
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Destroy the object and tagging it for GC? I don't agree, Dispose can only release managed/unmanaged resources, how does it make it eligible for GC? GC only checks for the reachability of objects, AFAIK and calling Dispose doesn't help in getting it GC'ed.
Generally, Close and Dispose are supposed to do the same thing. What connection object are you talking about? In case it is an SqlConnection, the MSDN doc clearly says "If the SqlConnection goes out of scope, it is not closed. Therefore, you must explicitly close the connection by calling Close or Dispose."
BTW, remember about the other thread where we were discussing about connection pooling. The MSDN doc for the Close method says "It then releases the connection to the connection pool, or closes the connection if connection pooling is disabled.". So obviously, if you use connection pooling, pooled database connections remain open.
Regards
Senthil
_____________________________
My Blog | My Articles | WinMacro
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My mistake! RectalCranial Inversion...
In connection pooling, you're right, the connection remains open. But it has it's appropriate uses. A single user application is not one of them. In the case of a Web Site, on the other hand, connection pooling is a beautiful thing, because connections must be recycled quickly to maintain performance for thousands of page fetches and database accesses per second. A single user application simply doesn't need that kind of performance, (and I'll add the obligitory "except in special cases" here.)
RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome
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Senthil,
Is connection pooling turned on by default?
On the other hand, use the Close method or the "using" would be the right way, according to MSDN doc. Am I right?
I find something else from MSDN "Dispose method calls Close, and returns the SqlConnection to the connection pool"
It is very confusing.
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Yes, connection pooling is turned on by default.
You don't need to worry about it though, you just call Close or Dispose on the connection, either direcly or through the "using" statement. The framework takes care of putting the object back to the pool (if connection pooling is on) or really closing the connection (if connection pooling is off).
Regards
Senthil
_____________________________
My Blog | My Articles | WinMacro
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Hey!
I have the folowing string
"\nHEY\r\nThis Test\r\n\nTest running in OS\r\n\nRE: Test 38"
When adding this to a richTextBox it shold look somthing like this
-- START --
HEY
This Test
Test running in OS
Re: Test 38
-- END OF STRING --
But instead it ends up like this
-- START --
HEY
This
Test
Test runnin
g in OS
RE:
Test 38
-- END OF STRING --
How is this posible?
The string is added by using invoke to the richtext box
<br />
rtIncomeLogg.Invoke(new DelegateAddDataToLogg(addData), new object[] { this, data });<br />
data is the string.
<br />
private void addData(object inSender, string inData)<br />
{<br />
try<br />
{<br />
rtIncomeLogg.AppendText(inData);<br />
<br />
rtIncomeLogg.Focus();<br />
rtIncomeLogg.Select(rtIncomeLogg.TextLength, 1);<br />
rtIncomeLogg.Select();<br />
<br />
}<br />
catch (Exception ex)<br />
{<br />
MessageBox.Show("Error in " + this.ToString() + " - addData : " + ex.Message);<br />
}<br />
}<br />
<br />
Any ide?
Best Regards
SnowJim
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It's because both \r and \n are converted in the richtextbox to a linebreak.
You only need to use either \n or \r. If you use both, as in CRLF, it will convert them into two linebreaks.
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Okay, but if you look at my ex so can you see that a line break acures in the midle of a word with out any /r och /n, how cand this be?
The richtext box is big enouth so it have nothing to do with wraping i think.
Best Regards
Jimmy
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Have trayed to place the string in a file instead but its the same problem.
Pleas help!
BestRegards
SnowJim
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it is fixed, thanks anyway.
Apperently i was using writeline when i was writing to my stream, and this writeline is adding \n on the end of the data.
Best Regards
SnowJim
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trying to match a pattern for an application that I working on for my self and can't seem to grasp this pattern in the regex fashion
so the pattern I am trying to match
kbfi ksea sea bfi
([a-zA-Z0-9]{4})|([a-zA-Z0-9]{3}) sorta works but it doesn't work if I put in the (\s) to catch the space so it splits incorrectly. Pattern should match something with 3-4 letters like above anything more than 3-4 letters without a space should be ignored so no garbage like this
asdfkjasdf aodf
Also it should be able to match a single set without spaces
kbfi
should be detected as well. As for correctness of the actual data in the string it will be verified against data stored in db tables
Thx
Morgan
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I am trying to convert over a Crystal Reports report from using a database to using a dataset. That part seems to have gone along just fine. I followed the instruction Microsoft gives for doing that and also for creating an XSD dataset (which is how I was able to convert the report). I'm sure to most of you, the solution to my problem is simple.
Here's my problem: I don't know how to get data into that dataset. I can't use the standard method of creating an OdbcDAtaAdapter and doing a Fill into the DataSet. I've tried, it doesn't work. I keep getting the following error if I try:
Fill: SelectCommand.Connection property has not been initialized.
Here's the command that generates the error:
daDalyORHED.Fill(dsDalyData1, "orhed");
Here are the relevent parts of the code:
daDalyORHED = new OdbcDataAdapter("SELECT * FROM PUB.orhed orhed WHERE OrdNum = '" + strOrdNum + "'", connDaly);
connDaly = new OdbcConnection("DRIVER=MERANT 3.60 32-BIT Progress SQL92 v9.1D;UID=userid;HOST=siifpa001;PORT=apluslvsv;DB=apluslv;PWD=password");
dsDalyData dsDalyData1 = new dsDalyData();
Obviously, dsDalyData is the name of my XSD dataset.
Can anybody please help me get my DataSet populated? It's kinda useless without that. 
--In a world without fences, who needs Gates?
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It not the typed dataset's fault... something is wrong with your connection.
Try to put connDaly = new... before the first line you posted (... new OdbcDataAdapter).
It should work.
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first drag n drop sqldataadpter component on ur form
then one wizard will be shown
click on the next option then it will ask for the server name
give . for local host
if u r using sql server authentication select that radio button
else
select windows authentication
if u select sql server then give user name and password
u acan leave password blank by checking allow blank password
after that u give the database name u want to use
and click on test connection
if it give one message window with "TEST SUCCEED" then click
ok
and
next
there it will show u one query6 builder button click on it
it will give u a list of ur tables in the database
select tables from the list and add
after rhat click next
and then click on finish
it will automatically create a sql connection for u
then right click on sqldataadapter pasted on ur form
one menu will be shown to u
choose generate dataset
use typed dataset
and click ok
after that drag n drop one datagrid on ur form
write the following code in the page load event
sqlDdataAadapter.Fill(dataset name);
DataGrid1.Databind();
set properties OF
DATA GRID
DATASOURCE NAME
DATATEXT FIELD
TRY IT IT WILL SURELY WORK
BEST OF LUCK
TripathiH
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hi,
i have a problem regarding this piece of code it throw an exception ("time out expired ") can anyone tell me why
<br />
try<br />
{<br />
Stream reqStream = webRequest.GetRequestStream();<br />
reqStream.Write(requestBytes,0,requestBytes.Length);<br />
reqStream.Close();<br />
HttpWebResponse webResponse=(HttpWebResponse)webRequest.GetResponse();<br />
if (webRequest.HaveResponse)<br />
{<br />
foreach(Cookie retCookie in webResponse.Cookies)<br />
{<br />
bool cookieFound = false;<br />
<br />
foreach(Cookie oldCookie in ccContainer.GetCookies(destination))<br />
{<br />
if (retCookie.Name.Equals(oldCookie.Name))<br />
{<br />
oldCookie.Value = retCookie.Value;<br />
cookieFound = true;<br />
}<br />
}<br />
if (!cookieFound)<br />
ccContainer.Add(retCookie);<br />
<br />
} <br />
if ((webResponse.StatusCode == HttpStatusCode.Found) || <br />
(webResponse.StatusCode == HttpStatusCode.Redirect) ||<br />
(webResponse.StatusCode == HttpStatusCode.Moved) ||<br />
(webResponse.StatusCode == HttpStatusCode.MovedPermanently))<br />
{ <br />
WebHeaderCollection headers = webResponse.Headers;<br />
return SendRequestTo(requestBytes,new Uri(headers["location"]),credential); <br />
}<br />
StreamReader stream = new StreamReader(webResponse.GetResponseStream());<br />
string responseString = stream.ReadToEnd();<br />
stream.Close();<br />
return responseString;<br />
}<br />
throw new ApplicationException("No response received from host.");<br />
}<br />
catch(WebException e)<br />
{<br />
Trace.WriteLine("Exception occured " + e.Message);<br />
throw new ApplicationException("Exception occured while sending request.",e);<br />
}
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If "time out expired" is the exception text, then that is the reason your code has a problem. Try changing "e.Message" to "e.ToString()" so you know which line had the problem (you might get a little bit more information, too).
Some of the basic reasons for a timeout are that the server isn't up, you have a bad address, or your connection to the server has been interrupted somewhere along the way.
John
"You said a whole sentence with no words in it, and I understood you!" -- my wife as she cries about slowly becoming a geek.
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Hey!
If i create a byte[] like this
<br />
byte[] tmpData = new byte[1024];<br />
tmpData will have 1024 elements, all set to "0"
The data i will add to this byte array could be 0 how do i now what place i shold write on next time?
ex
first write
element 0 1 2 3 4 5 6 7 8 9 10 11 12 13
data 24 0 5 21 6 4 14 2 9 18 0 5 4 0
if i then whant to add more data to this byte[], how do i know that element 14 is the next place to add data if a regular element in the byte[] is 0?
Maby i could set all elements to -1 on creation, and then test against this, but this will be alot of test(preformance).
I could also store a extra int that keeps track of where to write the next turn, but this will be som extra class and vaibels.
Is there another way to do this?
Best Regards
SnowJim
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