A function of my app is to encrypt a file with TripleDES. The problem is that when the app reads the data, encrypts it, and writes it back, the new data is appended. I need it to overwrite the original contents.Here is the code:
Dim
DES As
New
System.Security.Cryptography.TripleDESCryptoServiceProvider[code]............
I am writing an app that reads from the com port, filters the data, then writes to the text box, then immediately starts over. This all takes place in an endless " do while" loop within the "start" button code. I also have a end button too which closes the com port and ends the program. Some other buttons are present also to change the filter settings.Problem is when I click start, data is logged, but none of the other buttons work. Also some of the text boxes are "see through" and dont look like thy have updated with the rest of the form.
View 9 RepliesI should create a program for a Pocket PC that reads & writes data from an MSAccess database located on a desktop computer (pocket PC and desktop one are connected through a Wi-Fi connection).Is that possible?
View 3 RepliesI'm launching my application at the end of installation using custom installer class - Sub oncommited.I'm using vb 2005 setup project.The application main form load event need to read/write values from HKCUSoftwareMyApp registry.The problem is that when the application is launched at the end of installation ,it reads/writes from HKEY_Users.DefaultSoftwareMyApp instead of HKCU though I've written
My .Computer.Registry.CurrentUser.CreateSubKey(RegKey).GetValue("Name","")
When the application is launched through Program files shortcut,it reads/writes properly.I need to exit the application depending on registry values.
I'm currently finishing up a project that reads / writes to an access database. The only issue I'm having is that it needs to have the file path to the database file. EX:
[Code]...
I'm having a bit of trouble with the SerialPort class I'm hoping someone might be able to shed some light on. Specifically, writing to the port appears to work without incident. However, reading data is proving problematic. Initially I thought it was my hardware, but testing suggested the fault lied in software. I was able to confirm this with the installation of a loopback device on the port. It tends to be missing bytes, inserting bad bytes, and shifting bytes randomly.
[Code]...
I am new to VB.net. I want to read and input file and store that data to an SQL Server database. Do you have an sample code that do such?
View 1 RepliesI have a program that currently takes data and writes it to a MS Excel spreadsheet. (automatically opens the program, creates the cells, and fills them with data)
I would like to add an additional feature to my program that offers support for OpenOffice.org's 'Calc' spreadsheet program. (so users without MS Excel can use the application) So I am basically asking if anyone knows how to automate OpenOffice 'Calc' from VB.net. (I am using Visual Studio 2005)
I have searched on the OpenOffice forums but no one seems to know the vb.net code for this. So I was wondering if anyone here has done this, or would know how to do this.
I have two issues I am trying to correct...First am trying to get my listbox1 to be the selected Comport used to do the send data and get data back.
My second issue is its requiring me to send two times to get my read data back as complete data and has odd shapes with the data I get back in front of and after the regular txt.
Beware, I am very new at this so please take it easy on me... Most help I did find was for older versions I only have the 2010 Visual studio Professional...
Public Class Form1
Sub GetSerialPortNames()
End Sub
[CODE]...
I have a situation where I serialized data from a dataset to an xml file as a method of backup.I am trying to get the data deserialized back to the dataset.But for some reason, I cannot get the data to persist back to the DB.I don't receive any error messages either.The first chunk of code is the serialization code and the second chunk is the deserialization code.I can show that the deserialization back to the dataset is complete because this code in the 2nd block DataGridView2.DataSource = Movie_dbDataSet.movie_tb - displays the data in correct form all it is all there in the datagridview2.I call the update method but it does not get persisted back to the db.[code]
View 3 RepliesI have a USB device which creates a Virtual Serial Port on Windows. I am using VB.Net to write and read from the port. My device responds with specific sized set of bytes, but I am finding that SerialPort.Read(byte-array,offset,number-bytes) does not return the full number-bytes but it also does not timeout or generate an exception. Repeated calls return additional fragments (up to 3 calls required). Python code using pySerial does not have the same problem.So, what am I doing wrong here? Am I expecting too much?
Some scenarios are:I write a command to the port and expect to get 4 bytes in response. I get 1 byte first and then 3 bytes on the subsequent call.I write a command and expect 21120 bytes in response. I get 1, 12671 and then 8448 bytes in 3 calls to read from the port.
Here are some excerpts from my code:
Private Sub SetupVirtualSerialPort()
Dim portName As String = "COM" + (m_DeviceContext * -1).ToString
Const baud As Int32 = 9600 '7680000
Const parity As Parity = parity.None
[code]....
I'm trying to make a simple Class that reads data from a SerialPort.The Device returns a number of lines of Strings.[code]However running this code in a Form with one TextBox Control (txtLog) Allways results in the "The operation has timed-out." Exception.[code]
View 3 RepliesI am using VS2008(VB.NET) and SQL Server2000. I want to make an application which reads files and Insert Data into SQL. If first file has some error. Write into log and Move Next file for Proceed. How can I do that.
View 3 RepliesI have the following code, which reads data from xml file and displays it in the datagridview. It all works fine:
[Code]...
Instead of showing read data in datagridview, i'd want to read the data from xml file into one dimensional array: X(Impedances) Or is there a way to read value from this datatable into string variable without getting data from datagridview? The point is: i'd want to scan through all "Impedance" values (which are read from xml file) and compare with value y to catch the nearest value to y. How to do that?
I am using VB.net 2003. I am working on a stand alone windows program that stores data in an Access database via ADO.net via MS jet 4.0 OLEDb. I have progress to the point that I would like to provide the end user the oportunity to back-up the data they have stored and re-install if they choose. I am envisioning a menu item for "maintenance" with sub-items for "back-up" and "restore". I can create the menu items, but I can not find any information on how the back-up should be done.
View 4 RepliesI am writing an automation program for an associated research HYPOT tester and one of my current problems is trying to split the data i recieve back from the box.Currently i have two commands i use TD? and SALL? both do the same thing but return different data. TD? when sent to the box will return the test results and of course there is no auto return when test is complete so i have to either set some kinda of timer to get the data after the test is complete or just keep pinging the box tell the test returns with either a pass or fail.my problem is when i ping the box with TD? it returns
"M11,ACW,test results{pass|fail},1.50,10.00,10ms"
What I am trying to do is use a split command to split that line into strings based off "," as my dilimeter. Currently i am useing this set up
dim resultstring as string = main.serialport1.readexisting
dimresultarray as string = split(resultstring, ",",6)
txtTestResult.Text = resultarray(2)
for the most part is does return the test results but other times it will either error out saying that resultarray(2) is out side the index or it will display one of the other strings (acw or 1.50).Is there a more accurate way to do this.I am also printing the full string pulled from the buffer into a text doc as a data log.
Here's the function I'm a bit mystified by(Little rusty bitwise operators)
void two_one(unsigned char *in,int in_len,unsigned char *out)
{
unsigned char tmpc;
int i;
[CODE]...
I marked the two places that I don't quite understand. How to convert those pieces to Vb.Net.
Update: So this is what I came up with, but it's not quite giving me back the right data...Anything look wrong here?
Public Function TwoOne(ByVal inp As String) As String
Dim temp As New StringBuilder()
Dim tempc As Char
[code].......
I have an xbap application that connects to a webservice to run different stored procedure. The webmethod loads the data into a data table and returns it to my xbap application. My program gives the user the option to manipulate the data. What is the best option for saving the data back to the database?
View 6 RepliesI am having a problem with an application that displays data in datagridview depending on a selection from a combo box.The problem occurs when I want to write the data back to the database.
I get the following error:"Update unable to find TableMapping['Product'] or DataTable 'Product'."
Is this because the table in the dataset is filled in a private sub? If so how do I make it public?
Any ideas what is wrong. Code is as follows:
[Code]...
I have a hardware which sends out packets containing 17 bytes to the comport in bursts of 3. the little test VB that I have written receives and displays the bytes in a line of 17 bytes long and works fine until it gets to around 170th packet, then it starts to mix up (looks like shifting the data left) the bytes shift mostly by one digit sometimes by two. then it will continue to give almost a packet correct and a packet shifted for about 50 packets. Then it will correct itself for a long while, but then the speed at which it receives drops. All the packets are sent 3 times, and before things go wrong (within the first 170 packets) the packet counter shows that it receives 3 packet each time but after the problem it goes to 2 packet per burst and then to one.
If i close my VB monitoring program say at packet 165 and immediately open it again, it wont go wrong for another 170 packets, this points the finger at VB. I have check my hardware, there is no problem with that.The program reads port - waits for 17 bytes - once 17 has been received it will go and buffer the packet in an array. In fact they are 2 arrays but printing fro either results in the same problem.I have tried whatever i could think of but to no avail, i am wondering if some kind of house keeping needs to be done to clear something... I am sorry the program is a bit messy but I have been making many changes to find out what the problem is - my code below:[code]
I'm currently working on a program that would take the binary data from my access database and convert it back into jpeg format so I can store the images in a folder. I'm really new to VB so right now I'm pretty much stumped.
Code:
Option Explicit On
Public Class Form1
Private cn As ADODB.Connection
[Code]....
I just need to edit one field on a datarow and save the changes back to the database. My database is SQL Compact 3.5
I tried many methods but change is not saved to database.
Me.taSet.Fill(Me.Dsset.tblQuestions)
Dsset.tblQuestions.Rows(1).BeginEdit()
Dsset.tblQuestions.Rows(1).Item("ExamID") = "EDITED"
Dsset.tblQuestions.Rows(1).AcceptChanges()
taSet.Update(Dsset.tblQuestions)
I have an existing WSDL which returns information to remote devices using SOAP. However, I'm writing a new app with Android which doesn't support SOAP so I can't use the existing WSDL and have had to code a new app which looks for a querystring from the Android app and returns the data in a JSON packet. I've coded the module which receives the data okay but I'm unsure how to send the data back in JSON forma
View 1 RepliesIn a threadpooling situation is it possible for a modal form to be opened and data from that form to be passed back to the thread that opened it ?
View 1 RepliesVB.NET i have only one colum in back end database that is roll. .. Now i want to update a particular data .. the data types is integer.. i has a data like 12 and i ant to update it 13 how can i do..
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I need to send data back to my Apache web server so it can be updated in it's MySQL database, I've looked at NuSOAP as it's written in PHP but man that's hard. I'm lost, is there a more simply way to send it back? even to call a webpage and send data into it?
View 4 RepliesBasically I have:
vb
Public WithEvents PingReply As System.Diagnostics.Process
Public Sub Ping()
Dim PingServer = New Diagnostics.ProcessStartInfo
[code]....
But the event never gets called?
I want to change the back color of a row in a data grid view while the program is running.
View 2 RepliesI have store the variable in
Dim Lastname, Surname, Middlename, age As String
and the data are saved in notepad. how can I put them back in their exact label.one of my lable is
lbl_surname.Text
Using 2008 VB.Net trying to do serial communications. I have a Scantron scanner I can send data to it, but I can not get read data back sent to my serial port. I have tried ReadLine, ReadByte, etc. but i'm not capturing anything, and I don't understand the DataReceived event. [Code]
View 15 Replies