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SQL Command:
-------------------------------------------------
USE MyDB
SELECT SUBSTRING(HEXTEXT, 1, 100) AS HEXTEXT
FROM MyTable
WHERE MyID=200
-------------------------------------------------
In SQL 2005, this returns:
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0x680065006C006C006F002100
the Hex representation of 'hello!'
-------------------------------------------------
I try to get it back into my VB.NET app using:
------------------------------------------------------------------------------------------------
ConnectionString = "Provider=" + Provider + "Driver=" + Driver + "Server=" + Server + "; Database=" + DB + "; UID=" + Username + "; PWD=" + Password + ";Trusted_Connection=yes;"
Dim queryString As String = "SELECT SUBSTRING(HEXTEXT, 1, 100) AS HEXTEXT FROM MyTable WHERE MyID=200"
Try
Using connection As New OdbcConnection(ConnectionString)
Dim command As New OdbcCommand(queryString, connection)
connection.Open()
Dim reader As OdbcDataReader = command.ExecuteReader()
While reader.Read()
MsgBox(reader(0).ToString)
End While
connection.Close()
reader.Close()
End Using
Catch ex As Exception
MsgBox("Something database related screwed up.")
Exit Sub
End Try
-------------------------------------------------
When I run this i do not get any errors, i get 'System.Byte[]' in my message box? What gives? 
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You get that because you called the ToString method on an Array. This will NOT automatically convert the numbers in the array to characters or to a string of numbers.
What's the output you're looking for? Provide an example of what you want it to look like.
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I would be more than happy with my datareader returning the hex characters to me. If possible, converting it to the ascii would be even better, but hex would be a great place to start!
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svanwass wrote: I would be more than happy with my datareader returning the hex characters to me.
It looks like you stored a string in the database, that looks like "0x680065006C006C006F002100". So, you're looking to convert this string of characters into an array of numbers?? Like "0x6800" would become an integer 6800h, and so on down the line?
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The information was stored as data type 'image'. 0x680065006C006C006F002100=hello! in ascii. Does that make more sense?
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That would explain why it's being returned as an array of bytes.
Ascii is a set of characters numbered 0 thru 128. An extended set goes to 255. What you have in this array is UniCode. Every other byte is 0x00, giving it away. What the Reader returned was equivilent to:
Dim bytes() As Byte = {&H68, &H00, &H65, &H00, &H6C, &H00, &H6C, &H00, &H6F, &H00, &H21, &H00}
You can convert this array of bytes to a string using:
Imports System.Text
.
.
.
Dim str As String = Encoding.Unicode.GetString(bytes)
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Rock out! I changed it up to
Dim str As String = Encoding.Unicode.GetString(reader(0))
and it works!
On a side note, I DID scour the MSDN articles, CodeProject, and Google but never found what i was looking for. This is more than likely because i am not sure what topic i would need. Knowing where i fell down, any suggestions on topics to read up on?
THANKS A MILLION!
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Well, that's the hardest part about learning the .NET Framework. It's massive collection of thousands of classes, containing tens-of-thousands of methods and properties. It involves LOTS of reading  and experimentation.
About 6 years ago, when I got my hands on the Beta for .NET 1.0, I started by reading whatever documentation I could find in the MSDN Library, evaluating which namespaces were going to help me the fastest and built from there.
Today, I probably suggest picking up a beginners book on VB.NET and start reading through the clas documentation in the following namespaces:
System.Collections
System.Data (stick to OleDb for now)
System.IO (just the root, not the child namespaces under it!)
System.Text
System.Windows.Forms (just the root, not the child namespaces under it!)
Then start adding other stuff like System.Xml and System.Runtime.Serialization.
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I seem to have run into a second problem that seems to be related. For my sample data, I have
"
hello!
GOODBYE!
hello!
GOODBYE!
BONJOUR!
HALLO!
NOWAY!
"
in the cell that i am pulling from with your code. When i run it, i only get this much:
"
hello!<cr><lf>
GOODBYE!<cr><lf>
hello!<cr><lf>
GOODBYE!<cr><lf>
BONJOUR!<cr><lf>
HALL
"
As you can see, there is some missing text (O!<cr><lf>NOWAY!).
Could this be related to Encoding.Unicode.GetString(reader(0))?
I am storing the result in a string so I do not think that it is getting chopped on that end.
The While reader.Read() does not execute a second time (my first thought was that there was a limit to how much it could take).
If you have the time or the patience, your help would be greatly appreciated.
-Steve
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It's possible. Two 0x00 characters in a row would normally denote the end of a string.
Why are you using a binary data type for storing string data?
I really can't tell you what's wrong. There's a bunch of different places this can fail, such as what the code looks like that stored the data, if the data get stored properly, if the encoding is consistent throughout the data, ...
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I found a fix for it. I changed from using System.Data.ODBC to System.Data.SQLClient. That does not limit me at all.
Dim myConnection As SqlConnection
Dim myCommand As SqlCommand
myConnection = New SqlConnection("server=" + Server + ";uid=" + Username + ";pwd=" + Password + ";database=" + DB + ";Trusted_Connection=yes;")
'establishing connection. you need to provide password for sql server
Try
myConnection.Open()
'opening the connection
myCommand = New SqlCommand("SELECT *FROM MYTABLE WHERE MYID='" + MYTHING.ToString + "'", myConnection)
Dim dr As SqlDataReader = myCommand.ExecuteReader()
While dr.Read()
'mystr = dr.GetString(0)
'reading from the datareader
MsgBox(Encoding.Unicode.GetCharCount(dr(0)))
mystr = Encoding.Unicode.GetString(dr(0))
MsgBox(mystr)
'displaying data from the table
End While
dr.Close()
myConnection.Close()
Catch
End Try
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Does anyone know how to do the following:
If listbox2 contains recycle.wav do not add recycle.wav to listbox1.
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Why not just enumerate the items in the ListBox, comparing the one your searching for to the items in the list?? If you find it, don't add it to ListBox2.
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Hey,
I'm trying to use the DoCmd.SendObject to send an email. The last paramater, it asks for a template file. If I have an .oft (Outlook File Template) saved, can I just put the path into there? I've tried just putting the path in as a string and it doesn't open up the template file. Can anyone please help me out with this?
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Hi all,
I am developing a windows application in VB.Net.
I am using datagrid with direct editing option.
In datagrid, when editing any particular cell, the arrow pointing towards to the edited row in the left side changes to edit mode , i.e., it displays like a pen.
At this time when I change, edited record is not updated.
What event fires when editing a datagrid cell?
Thanks in advance,
Senthil
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Senthil_GeoEdge wrote: At this time when I change, edited record is not updated
What do yot mean by this? Are you saying that you can't change the data in the datagrid or you can't update the data in the database? How are you triggering the code to save the new data? What does the code look like that does the database access?
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I have my project on network which having windows2000 server.
I make a connection in my project.
when i run it without copying it to local machine i get error message,it shows some permission problem.but when i copy same project to my local machine which having xp it give output
my local machine have all the rights for database.i used sql server 2005 and vs 2005.
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So if I get this right...
Ajeet mittal wrote: my local machine have all the rights for database
so your local machine has permissions but the other doesn't.
Ajeet mittal wrote: when i run it without copying it to local machine i get error message,it shows some permission problem
When you run it on the other machine it says you don't have permission.
Ajeet mittal wrote: but when i copy same project to my local machine which having xp it give output
But when you run it on your machine it works fine.
Could it be that it works fine because your machine has permission and the other doesn't?
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Ajeet mittal wrote: I make a connection in my project.
Connection? To what? What code did you use? What's the connection string you used if this is a database? Is this SQL Server 2005 Express Edition?
Ajeet mittal wrote: when i run it without copying it to local machine
Copying WHAT to the local machine?
Ajeet mittal wrote: i get error message
And that would be??? Without knowing this, we're all just wasting our time...
Ajeet mittal wrote: but when i copy same project to my local machine
You already said you did this and it failed! So, which is it?? Did the project work on the local machine and fail when you copied it to another computer??
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Sir,
I make connection with the statement-
dim con as new sqlconnection("Servername with database and uid ,pwd")
I am using sqlexpress edition.also
when i execute my project after coyping complete project to any local machine from server it gives my form without error and if i try to execute same project on the server location it gives permission error.
i also copy bin folder to server from local machine to server location and try to execute it from there,i means to say i try to run exe from server its shows permission error.As this having compiled code.
tell me solution what i have to do for it.
ajeet
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Right, did you read my reply to your original post?
If it's giving you a permissions error its to do with the permissions ... it's pretty easy to work out.
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Ok! So whats your connection string like? By default, SQL 2005 Exp. Ed. only has SM enabled. If you want to use TCP/IP or named pipes, you need to turn it on using the SQL Server Configuration Manager.
My guess is that this all will go over your head. But let me put it this way.
1) You cannot remotely connect to SQL Server Express by default. You need to configure it to accept rmote connections.
2) If your connection string resembles something like this
Data Source=.\SQLEXPRESS;AttachDbFileName=e:\data\aaa.mdf;Integrated Security=True;User Instance=True
Then you're using shared memory to access it.
3) If the above is true, you need to copy the DB file to the "other" machine as well, and I guess it also should have Express Edition installed.
(Or)
If you want to enable remote connections, change your server configuration using the server manager and change your connection string. And that would seem pretty complicated if you do not know what you're doing.
So for a start, start reading the Express Edition documentation.
SG
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And on top of what Simulation said, if you copied the code to a file share and are running the code from that share, you need to take into consideration Code Access Security. Managed code running from ANY non-local source (i.e.: network) runs in a restricted sandbox. If I understand your explaination correctly, this is probably where your "Security Exception" is comming from.
Bascially, the users machine doesn't trust your code. You have to tell it to trust the code. Read[^].
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I'm trying to make windows local users with VB. This is no problem. I'm stuck trying to set the environment settings for that local user. For starting after sign on with RDP. Is this possible anyway? Maybe somebody can put on the right direction.
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