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thanx so much for responding to my post.
i cant even figure out if the USB port is empty?
i will tell u in detail what i am supposed to do in my program.
->There are two options in my GUI, Serial Port or USB port. Depending on which port the user selects i must transmit data through that port.
-> If the user selects Serial port it is pretty simple as even the COM port will be selected by the user.
-> As i had mentioned longback that i am using "USB to RS232 converter" which makes USB port look like a COM port and some COM port number(other than the available physical ports) will be allocated to USB port by the software.
->If USB is selected by the user then i must be able to display an error if the cable is not connected and the user is trying to communicate through that.
-> Usually the last valid port will be the COM port allocated to USB port by the software(USB to RS232 converter). The COM port will be allocated to USB port only after a USB cable is plugged in to the USB port.
-> In my program i will be finding out the last valid port available and that port i will be using for communicating through USB.In case if the USB cable is not plugged in then i will assume someother physical port as the one allocated for USB port.To avoid this error i must find a method by which i can find out what is the COM port number allocated by the software to USB. I am not able to find any method for this . So i thought it will be better if i am atleast able to find out whether USB port is plugged in with a USB cable
Hope you got what is my problem
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In that case, don't worry about the USB cable being plugged in. Since your app is communicating over Serial ports only, no matter what the cable medium is, your app doesn't change if the cable changes. So why are you complicating your code over something your code doesn't care about in the first place?
There is nothing that maps COM ports to what cable they're on, if they are simulated, or implemented on hardware other than actual Serial ports. The driver you installed for the cable puts up the illusion of a Serial port, then quietly sits behind it, translating between serial comm and USB.
If the USB cable can be on any COM port, don't mess with USB. Just go through the COM ports and try to communicate with your target app on each one. If you get a response, you've found the port your need. If not, you'll have to rely on the user to tell you which port to use.
RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome
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After looking at msdn and various websites this should work
the sqlcommand object has all the connection info and opens without error
but it fails when trying to execute the reader
With SqlCommand1
.Connection.Open()
'.Parameters.Item(0).Value = TextBox1.Text
.CommandText = "SELECT MATTER_UNO FROM(HBM_MATTER)WHERE (CLNT_MATT_CODE = '" + TextBox1.Text + "')"
.CommandType = CommandType.Text
Dim reader As SqlClient.SqlDataReader = SqlCommand1.ExecuteReader()
'Console.Write(.CommandText)
While reader.Read
Global.Matter_uno = reader(0)
End While
.Connection.Close()
End With
could do with some help
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skippydog wrote: CommandText = "SELECT MATTER_UNO FROM(HBM_MATTER)WHERE (CLNT_MATT_CODE = '" + TextBox1.Text + "')"
You had the right idea starting with the previous line by adding parameters, but you seem to have decided to inject the value from the text box into the SQL directly. You should really read up on some SQL Security, unless you want your server to be 0wn3d: SQL Injection Attacks and tips on how to prevent them.[^]
Now, to your question: What was the error produces. I can see nothing much wrong with the code (apart from the security hole I indicated above)
ColinMackay.net
"Man who stand on hill with mouth open will wait long time for roast duck to drop in." -- Confucius
"If a man empties his purse into his head, no man can take it away from him, for an investment in knowledge pays the best interest." -- Joseph E. O'Donnell
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finaly solved it by putting a return parameter into the parameter collection and executescalar() as all I wanted was one field from one row. for the textbox I can write a validation routine that will check the format of the string to be passed but only when the app gets anywhere near to being tested by someone.
thanks for the input
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skippydog wrote: but only when the app gets anywhere near to being tested by someone.
Surely you are someone and you are testing the application all the time. Security is not something to be tagged on at the end. It is something that should be in up front at the start or development and stays all the way through to the end.
ColinMackay.net
"Man who stand on hill with mouth open will wait long time for roast duck to drop in." -- Confucius
"If a man empties his purse into his head, no man can take it away from him, for an investment in knowledge pays the best interest." -- Joseph E. O'Donnell
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I use DirectX.AudioVideoPlayback to play video, which require any control to be an "owner" in which it plays video. Now I selected to play video in Panel control & wanted to save snapshot/picture of any paused frame. Thats taking picture from movie.
Tell me how can I do this (please include coding if possible)
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AudioVideoPlayback is no longer supported, and won't come out in future versions for .NET 2.0 at least. However, you should be able to render to a texture, which you can then save.
Christian Graus - Microsoft MVP - C++
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"However, you should be able to render to a texture, which you can then save."
Please tell me how can I do this in VB.NET with .NET Framework v1.1.
Also whats new in .NET Framework v2.0 about saving pictures from movies.
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Iftikhar Ali wrote: Please tell me how can I do this in VB.NET with .NET Framework v1.1.
I've never done it, I've just read the docs
Iftikhar Ali wrote: Also whats new in .NET Framework v2.0 about saving pictures from movies.
The AudioVideoPlayback namespace is gone. There's nothing new that's good that I know of.
Christian Graus - Microsoft MVP - C++
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Christian Graus wrote: I've just read the docs
Please tell me the source of docs.
Christian Graus wrote: The AudioVideoPlayback namespace is gone. There's nothing new that's good that I know of.
Thats really bad, but I think some other namespace will replace it but it cannot be completely removed.
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Iftikhar Ali wrote: Please tell me the source of docs.
They are in the SDK, but I also bought a book.
Iftikhar Ali wrote: Thats really bad, but I think some other namespace will replace it but it cannot be completely removed.
My fear is the new SDK will be WPF, which only runs on XP and higher.
Christian Graus - Microsoft MVP - C++
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Ok I'll search in the SDK, Please confirm me, you are talking about DirectX SDK?
Christian Graus wrote: My fear is the new SDK will be WPF, which only runs on XP and higher
Thats Microsoft policy to eliminate usage of old versions of Windows.
Tell me what WPF stands for?
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Iftikhar Ali wrote: you are talking about DirectX SDK?
Yes
Iftikhar Ali wrote: Tell me what WPF stands for?
Windows Presentation Foundatin AKA Avalon
Christian Graus - Microsoft MVP - C++
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Thanx
I know WPF as Avalon.
If possible tell me the link from which I can get my answer to this question.
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Private Sub txt_ord_qty_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles txt_ord_qty.KeyPress
If IsNumeric((e.KeyChar)) = False Then
MsgBox("ENTER ONLY NUMERIC VALUE")
End If
End Sub
I M USING THIS CODE BUT AFTER MESSAGE IT INSERT VALUE IN TEXTBOX
HOW CAN I PREVENT STRING VALUE IN TEXTBOX
PLEASE HELP ME
asdf
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Have you check if there's a cancel property available under e?
Otherwise strip last char in the text property.
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did u tried
return
after the msgbox in the if condition
abhinav
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hi vivek
the code that i m giving u will definately help u
in the key press event of the textbox write the following code
if char.isNumber(e.keyChar) = false then
e.handled=true
end if
karan jain(Vinit Jain)
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System.Data.OleDb.OleDbException: The statement has been terminated. Cannot insert the value NULL into column 'bcId', table 'ForumVB.dbo.forumTopics'; column does not allow nulls. INSERT fails. at System.Data.OleDb.OleDbDataReader.NextResults(IMultipleResults imultipleResults, OleDbConnection connection, OleDbCommand command) at System.Data.OleDb.OleDbCommand.ExecuteReaderInternal(CommandBehavior behavior, String method) at System.Data.OleDb.OleDbCommand.ExecuteNonQuery() at dotForumTopicAdd.addTopic.submitter_update(Object sender, CommandEventArgs e)
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It seems that the message tells the story.
Or you set a non null value for bcId or you make it nullable in the DB.
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yup, i set non null value for bcId, but i forget 2 set it automatic generate number because i use bcId is primary key and is not get the value from user keyin.... So after i set bcId to auto generate number in database then my erorr was solve already
anyway thanks for reply n all d best 2 u
-- modified at 6:06 Tuesday 17th January, 2006
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Hi. I think that I saw on a site that I can display Master and Details in the same grid with "+" on the left of each Master's row. and if I click on the "+" so it open the details rows in the same grid with few left margin increment.
can anybody help me please... I forgot where I can find this article
OmarMallat
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I have a picturebox for view some jpg file.
However, the jpg is always larger than the picture box view.
By default,
<br />
pictureBox.SizeMode = PictureBoxSizeMode.StretchImage<br />
after a button is clicked, it change to
<br />
pictureBox.SizeMode = PictureBoxSizeMode.Normal<br />
How can I view the whole 1:1 picture by the control of verticle and horizontal scrolling bar?
Any example/article for this?
Thank you!
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