I have created my own object, wich contains a SerialPort. I have a sub in my object wich handles the .DataRecieved-event. I'm trying to access my DataSet from that sub, but for some reason I'm unable to do that. It keeps telling me that my tables contains 0 rows, but I'm 100% sure that they contains several rows.
View 10 Replies
I am unable to access the TableLayoutPanel feature inside the toolbox in Microsoft Visual Basic Express 2010, I was wondering if this is a feature that is excluded from this package or is it something that I need to download.
View 1 Replies[Code] Somewhere my system haves a function that returns a DataSet with the books of a certain subject and all the Authors that wrote such books. I need to show the book's attributes in some textboxes inside a Form. I use a BindingSource to display the ISBN, Name and Subject of the books in a textbox, yet I don't know how to display the author name of the book I am currently viewing in a TextBox, taking into account I already fetched the Author into the DataSet.
Its pretty much the Child/Parent display problem somewhere discussed in the codebank, but kinda backwards, the thing is that I;m navigating through the CHILD records here, not the parent, yet i have all the data needed in my Dataset.
I am trying to make a new data connection to an Access DB using the Server Explorer. The connection test OK then when I click on the OK button to finish I get the following error message.
Unable to add data connection. Index was outside the bounds of the array.
I am using VS2010 and the 4.0 .Net Framework. I have found several posts on this but done have worked out.
I am using Access 2010 and VB in VS2010.I have created a DB and have several tables. 1 table in particular called Employers, has the normal AutoNumber Primary key. Everything in Access runs fine. I used Access to develop a basic model application of the full version I am developing in VS.My VB front end contains a dataset linked to the employers table. I have dragged onto my form the "detail" view of this DataSet, not the DataGridView. The usual controls are in place such as the EmployerBindingSource, EmployerTableAdapter, TableAdapterManager and a EmployerBindingSourceBindingNavigator.On my VB form Scrolling through the record set is fine and all works well.My problem is after I click the "Add" record button on the EmployerBindingSourceBindingNavigator. The form fields go blank as expected awaiting user input. However, the field that is bound to the employer_id field (the Employer table's primary key) shows a value of -1.The insert command works no problem, and having looked at the database the table contains the new record with a correctly incremented PK
[Code]...
I have a DataList inside another DataList. I want to access the child DataList "dlQuestion" events, ItemDataBound event. Also, I'm tring to find the control LableControl "lblQuestion" in the child datalist. How do I do that? Here's the mark-up:
<asp:DataList ID="dlSection" runat="server" Width="100%">
<ItemTemplate>
<div>
[code].....
I have a dataset and inside of it theres two(2) datatable. Is it possible to do this kind of query.
"SELECT DATATABLE1.NAME FROM DATATABLE1 INNER JOIN DATATABLE2 ON DATATABLE1.ID = DATATABLE2.ID"
am developing a project and i am trying to use this code with my table which is under microsoft access 2010
View 3 RepliesI 'm a beginner and have a project that I'm using to turn lights on and off. I need to use separate forms for display on remote monitors. My problem is each form needs the same serial port open to work and the port won't open unless it's closed in the previous form. Using a module works for opening and closing the port, but only for one round. If I try to revisit a form I already accessed it doesn't work.
Public Sub sp1(byval SerialPort1)If Form2.SerialPort1.IsOpen = TrueThen Form1.SerialPort1.Close() If Form3.SerialPort1.IsOpen = TrueThen Form3.SerialPort1.Close() Form1.SerialPort1.Open() end sub
Public Sub sp2(byval SerialPort1) If Form1.SerialPort1.IsOpen = TrueThen Form1.SerialPort1.Close() If Form3.SerialPort1.IsOpen = TrueThen Form3.SerialPort1.Close() Form2.SerialPort1.Open() EndSub
Public Sub sp3(byval SerialPort1) If Form1.SerialPort1.IsOpen = TrueThen Form1.SerialPort1.Close() If Form2.SerialPort1.IsOpen = TrueThen Form3.SerialPort1.Close() Form2.SerialPort1.Open() EndSub
end Module
So I just spent the last 4 hours trying to find out what was wrong with my code, just to find out that there's a bug in this version or I just don't have enough knowledge of VB2010 (I'm coming from VB6, this is my first program on 2010)I removed the rest of the code just to point out the problem, here it simply tries to enable the Timer1 when you receive data in the SerialPort1
Private Sub SerialPort1_DataReceived(ByVal sender As Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles SerialPort1.DataReceived
If Me.Timer1.Enabled = False Then
[code]....
After this I found that the code inside the Timer1 didn't run when the 100miliseconds passed, so I added a msgbox to see debug.
Private Sub SerialPort1_DataReceived(ByVal sender As Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles SerialPort1.DataReceived
If Me.Timer1.Enabled = False Then
[code]....
I am working on a simple vb project to read data from a PC serial port and write that data to a file.The data is ascii sent in Hex format. I used MySerialPort.ReadChar() to read data and MyStreamWriter.Write(MySerialPort.ReadChar()) to write it to a file.
I copied my code below, sorry about the format.The trouble is: MySerialPort.ReadChar() acts the same as MySerialPort.ReadByte() , both takes the Hex data input and returns data in decimal format.I tried to use Convert.ToChar(MySerialPort.ReadChar()) to covert decimal to char, but it's too slow.I tried decimal.ToChar(MySerialPort.ReadChar()), but VB doesn't recognize decimal.ToChar, even after I installed .NET4.
Did I do something wrong? how to make MySerialPort.ReadChar() to read Hex data and return char?
[Code]...
I'm trying to incorporate TransactionScope into my code and am failing at the first hurdle. I am unable to open a connection inside TransactionScope block. I get exception Connection Not Open.
Public Sub PerformDBWork()
Dim cnA As New OleDbConnection(My.Settings.DB_CONN_BUSINESS)
Try
cnA.Open()
[code].....
My cnA.Open() fires as expected but my call to cnBusinessDB.Open() fails.
I'm trying to create a Report. In my Solution I have a form with Report Viewer in it, a RDLC file and a DataSet. When I run the solution the report is populate OK no errors. I would like the User to be able to filter the DataSet so only the required data will populate the report. My DataSet contains the following columns Customer, Address, Orders. I have tried the following code but the Report is not filtered nor I get any errors.
[Code]...
I have a DGV which I am laying out in code as it is unbound. The problem I have is when it is inside a group box, it moves outside the group box to the top of the form.
If the DGV is not enclosed in a group box it stays put. I have tried docking the DGV to the group box but that does not work. If I have a dataset bound to the DGV, then there are no problems.
How can I keep the DGV inside the group box when it is not bound to a dataset?
I am trying (without success) to import a single dataset and apply various symbols to the mapped locations.The command 'objDataSet.Symbol' returns a single symbol for the entire dataset and I can't figure out how to parse through the records and assign a symbol based on the value of a specific field within the dataset. I have searched through the MSDN site [code]...
View 2 RepliesI am developing an application which uses a database that holds the information about a company and it's personnel. but when I try to edit already existing data in the dataset it just won't update it. I've tried all the method the MS sites provided me, but it just won't. the code looks like this: (notice this code wasn't complete)
[Code]...
i am making a table through vb.net code (htmltablecell, htmltablerow..) no this table populates with an sql query and works perfectly. but inside this table in one tablecell, i need to add a dropdownlist which shall require a completely differernt query and shall run on its own on each row. so the code is as follows
Sql = "..."
rd = ExecuteReader(SqlCnn, Sql)
Dim newcounter As Integer = 0
While rd.Read()
[code]....
the ??? in the code is where the dropdownlist shall get populated each time with its own datareader and while loop and query.
I wanna access the literal1 text which is placed inside panel 1 and panel1 is placed inside datalist1 ...
i wanna retrieve literal1 text on page load event using VB.NET
I have the following
Private ReportAdapter As OleDbDataAdapter 'used for controlling database
Private ReportTable As DataTable
Private ReportManager As CurrencyManager
[code].....
I have things set up so that the program is ready to start logging ,only when Recieving=true.This is controlled with Button1. So I click button1,Serial port is open and waiting for some signals from the Dyno.When 1 signal come it put a "1" in TextBox1 ,and for the second a "2" and so on. Thing is sometimes it starts right away, like I want it to,and sometimes it lags a fraction of a second, even though the Port is open.When it lags there are already 5 to 10 signals gone by before it starts logging 1,2,3,...and so on. Sometimes it don't start at all.Then I have to close and re-open the form and it works,but with lagging on the first "set"
"Textbox1 > 0 then" triggers a timer (not seen in this code)that samples Textbox1 once pre interval and writes the value to a listbox. On the upside as soon as a "1" is displayed in textbox1 the timer starts like it's supposed to.I noticed this behaviour before I added the timer and besides the timer has nothing to do with the signals coming from the SerialPort. I have my form setup so I can run "sets".Run one "set"...save...reset...run another "set" ...and compare.It's always the first "set" thats off.If I run multiple "sets" the first one is completely "whacked", and the rest are consistent.
Think this could be the SerialPort lagging,or code problems?
Public Class Form1
Dim resetValues As Boolean = False
Dim RPM As Double
[CODE]...
actually when I edit float value in datagridcell , I want only two numbers to be displayed after point(.)....i.e 2.35 instead 2.34567 more over am getting it but the actual thing is that value is not getting update in the dataset , but when I reload the form it shows like 2.34567 only instead i want 2.35...
[Code]...
I have a form that has 1 text box and has 2 queries that locate the data. One is by customer ID and the other is by customer last name. They both work but when the code works and the user enters a customer ID and the query locates it then enters a customer last name it also locates it. If the user enters the same customer id again the query seems to fail. This is why I'm sure I need to add some kind of code to reset the Dataset.
Here's the code in the load sub procedure:
EditBoxSearch.Focus()
' Start out clean.
[code].....
I have a dataset (WW1Dataset) with one data table(WW1).(database used in an access database) I'm trying to filter the dataset e.g a user wants to filter by a chosen surname (SurnameTextBox.text) so the datset is filtered to display only those records wherethe surname column in the dataset matches SurnameTextBox.text.
View 1 RepliesI'm using Visual Studio 2005 Team System For Software Developers. When I try to add a new DataSet to any kind of project, I cannot get to the visual DataSet designer. Rather, I get the following error (all the time no matter what the type project actually is - Windows app, Web site, etc.): The custom tool 'MSDataSetGenerator' failed. Unable to convert input xml file content to a DataSet. Data at the root level is invalid. Line 1, position 1.
View 3 RepliesHow can I access rep_DataSimilarToBacthid ? I need to bind the GridView and call GridView RowDataBound or InitializeRow
[Code]...
I am using VB.Net with Framework Version 2.0.
I am trying to utilize the access database, but I'm getting an error message: Value cannot be null. Parameter name: dataSet
[Code]...
That's the code I'm using, why I'm getting this error?
I"m developing a small app in silverligh with VB
I created an :SQL Database , ADO.Net model and a Domin service
The code was auto generated for me.
All im trying to is access the class and call my query.[code]....
I found this for Access Automation: How To Automate Microsoft Access From Visual Basic .NET
BUT, the "Imports" statement given on that page doesn't work in VB.NET Express 2008, so far as I have found. Imports Microsoft.Office.Interop
Why is this? Is there a way around it, without buying Crystal Reports or Visual Studio Pro?
[code] the part way at the end where it uses .elements(mySearchInput).Value = "bob" I get a compile error it says object variable not set? my guess is this text box is inside a frame called "mainframe" so how would I access an element inside of a web frame? it works fine on another site without frames?
View 1 RepliesI've got 2 DataTemplates defined for a Listbox Control. 1 Template is for the UnSelected State and the other one is for the Selected State(showing more detail than the UnSelected State).[url]...
about how to access the Elements inside the DataTemplates from Code behind.
I get it right, but it only finds and returns an element of the UnSelected DataTemplate. But when i search for an element in the Selected DataTemplate i get a NullReferenceException.
