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I am not sure this is the right place for this question but here it is:
Has anyone else had problems with the SqlCeReader.Read() ? Mine doesn't like reading type int from the database and i had to write the query like this (in order to avoid Data conversion failed. [ OLE DB status value (if known) = 2 ]):
SELECT OfficialRegNo, TransponderID FROM BasicAnimal UNION SELECT CAST(FilterObjectType AS nchar), Caption FROM Filter
so, before it was:
SELECT OfficialRegNo, TransponderID FROM BasicAnimal UNION SELECT FilterObjectType, Caption FROM Filter
Anyone knows why?
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You have a data type problem in your database. It would appear that you're trying to put a number is a string field or some other implicit conversion. Did you change a data type somewhere??
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Hi! The datatype in the DB is int and I am only doing a Select query. Only way I could get the Read() method to work was to typecast the int to a nChar. The problem table with an int is FilterObjectType. So I am not trying to insert anything here.
Well, no I haven't changed datatypes anywhere, only this query to the DB.
BTW, I am quering a Sql Server Ce .sdf DB in this case. Not the Express here (was a bit confused when writing prev mess).
This is the only code I have written for this so far is this:
SqlCeConnection conn = new SqlCeConnection();
conn.ConnectionString = "Data Source=todos.sdf;Persist Security Info=False";
SqlCeCommand comm = new SqlCeCommand("SELECT OfficialRegNo, TransponderID FROM BasicAnimal UNION SELECT CAST(FilterObjectType AS nchar), Caption FROM Filter", conn);
conn.Open();
SqlCeDataReader myReader = comm.ExecuteReader();
do
{
Console.WriteLine("\t{0}\t{1}", myReader.GetName(0), myReader.GetName(1));
while (myReader.Read())
Console.WriteLine("\t{0}\t{1}", myReader.GetString(0), myReader.GetString(1));
} while (myReader.NextResult());
myReader.Close();
conn.Close();
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If officialRegNo and filterObjectType are not implicitly convertible you will get this error in all versions of SQL Server.
Need custom software developed? I do C# development and consulting all over the United States.
If you don't ask questions the answers won't stand in your way.
Doing a job is like selecting a mule, you can't choose just the front half xor the back half so when you ask me to do a job don't expect me to do it half-assed.
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Is there a simple way of sorting a BindingList by the given object element?
A code example of the OrderBy function would be very helpful!
Thank you!
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I did, it does seem like an overkill since the BindingList has an OrderBy function. I just don't know how yo use it.
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If you want to support sorting, you have to derive your own class from BindingList. This[^] MSDN article explains why you should do that and how. Please read carefully, especially the "BindingList<t>: What's Missing" section.
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riddick_86 wrote: Please read carefully
Well that's an extremely high expectation round here.  Reading carefully is also considered overkill by most our members. Magic is preferred, or when not available a copy paste solution will do. 
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Thanks I'll check it out!
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riddick_86 wrote: you have to derive your own class from BindingList
Turns out there was a simple way after all.
listOfObjects = listOfObjects.OrderByDescending(c => c.NameAndSurname).ToList();
That was a list, then I just convert it back to a BindingList.
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Is "listOfObjects" a BindingList to begin with? If it is then you can't use this trick to sort the list as ToList() gives a generic list which cannot be converted to a BindingList, or am I missing something?
Rafique Sheikh
"The truth will set you free but first it will piss you off".
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Rafique Sheikh wrote: Is "listOfObjects" a BindingList to begin with? If it is then you can't use this trick to sort the list as ToList() gives a generic list which cannot be converted to a BindingList, or am I missing something?
Took some digging in our SVN to find that code.
"listOfObjects" is a normal List<>, which I sort as explained in my previous post.
I simply convert it back to a BindingList using a foreach loop, adding each object to the new BindingList one-by-one. I think it has a slight speed penalty, but it works great and I had no better workable solution at the time.
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Thanks for the reply. I see, that's what I thought. Actually the OrderByDesceending and OrderBy, both return an IEnumerableOrdered array which you can iterate over to do the same. I was trying to avoid because of the penalty and also for cleaner code. It is too bad that when you call OrderBy on a BindingList or any other such object the actual list is not ordered but rather you are returned an ordered list. I have the same frustration with this as I have with functions like Remove, Replace for strings etc. Why don't they change the object on which we perform those actions?
Anyway, I think I will have to derive from BindingList<t> and write my own SortableBindingList class!!
Rafique Sheikh
"The truth will set you free but first it will piss you off".
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BindingList<MyClass> b = new BindingList<MyClass>();
b = new BindingList(b.OrderBy( m => m.MyPropertyFromMyClass).ToList()));
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hello..
i have to send data i mean collection of5 string variables over the tcp connection using a socket. but the problem is that each time i have to ecode the string to byte and send. can i send all the strings as a collection of bytes or array and decode the sequence at the destination i.e the rciever... thans for any advices.... bye
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Yes, you can use the Encoding.GetBytes[^] method for encoding the strings into bytes,
then you can use Encoding.GetString[^] at the destination to decode the bytes into strings.
Edit: Sorry, I misread your post. What you want to do is to collect all strings, convert them into bytes and send them all at the same time - then decode them at the receiver. Let's say you have an array with the strings - use a StringBuilder and a foreach loop to build the strings into one big string. Remember to apply a seperator after each string:
builder.Append(theString + seperator);
The strings would then come out as (assuming semi-colon ( ; ) is the seperator):
hello;goodbye;hi;
At the receiver application you would then split the string (after decoding it of course) into an array to get each string.
I hope you could understand what I tried to say, otherwise ask.
![Green Alien | [Alien]](https://www.codeproject.com/script/Forums/Images/alien.gif) Kristian Sixhoej
"You can always become better." - Tiger Woods
modified on Wednesday, February 18, 2009 10:37 AM
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that was fine i got it... thank you for the keen interest.... have a gud day..
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You're welcome. 
Good day to you as well.
Kristian Sixhoej
"You can always become better." - Tiger Woods
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I have tried to follow a few, including some for here I believe, but I didn't find any explanations on the actual description of the logic of the implementation of the event, delegates and sender objects. Basically I'm looking for something that has both code and theory wrapped in an easy to digest package.
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[ShamelessPlug]I've just updated one of mine here[^].
Most of the theory is gradually introduced in logical, practical steps throughout the article, but the real deep stuff/theory is exluded and left to the other articles you've probably already found.[/ShamelessPlug]
DaveBTW, in software, hope and pray is not a viable strategy. (Luc Pattyn)Visual Basic is not used by normal people so we're not covering it here. (Uncyclopedia)
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thanks Davey, your tutorial looks fairly accessible to a non-pro such as myself.
I'll print it out fur further reading.
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