I have a data reader "dr " that returns a row fo data, Assume dr returns values of 6 columns I need to create an instance of DatarRow using "dr", so that later I can create a collection of datarow objects that I will be adding to a table. However, how do I create a DataRow using dr object?
View 1 RepliesI have two Combo-Boxes like this
I need to create an auto-fill feature for the 1st Combo-Box. It should list the EmployeeID if Search-By Field is specified as Employee-Number. Similarly it should list Employee First Name along with Last Name if the Search-By Field is Employee-Name.
How can I do this? I have no clue, I am doing this for the first time. I am using SQLite, Visual Studio 2010.
Dim mySelectQuery As String = "SELECT " & Search & " FROM EmployeeTable WHERE Status LIKE '" & Status & "'"
Dim myConnString As String = "Data Source=" & Application.StartupPath & "DatabaseSimpleDB.db3"
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how to pull/fetch data from SQL DB using Data Reader and loding to XML file.
After that I will have write code to read XML file and download to CSV file and Test files.
can data reader be used as a data source for a grid control?
View 5 RepliesI was create Access database with Access 2003. I create VB project with Visual Studio 2005 Standard With connection wizzard I create coonect with this Access database, select all tablesI see this database inside Data sources and inside Server explorer Test connection is OK When I drag and drop table from Data sources, Wizzard don't create DataGridView, DataSourceBinding etc .. and I see popup window with mesage: Object reference not set to an instance of an object and then "game over"
View 2 RepliesI want to create a class is it where I can do...
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How do I do this? Do i create a class and create a instance of CarData? but how do I add Color and Year etc to it?
I'm trying to write a simple game ui, it is grid/tile based, and i have the grid built using grid column and row definitions and I'm successfully placing objects in various grid locations. I am currently stuck as trying to build the player object. I want a single object reference to represent the various components of the players piece.
Currently I am using a polygon to represent the piece on the grid. Eventually I want to replace this with images or something. I want to add in properties for what weapon and armor it has equipped I want properties for health
Essentially in code i want something like this
dim player1 as new playerobject
player1.polygon.points = 0,0 60,30 0,60
player1.health = 100
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I can instantiate all this as separate variables etc, but I'd like to have a singular reference that contains all the variables, properties, objects, controls etc.
I'm using vb .net in vs 2010 (and no, I'm not looking to write in something else)
I'm trying to write a simple game ui, it is grid/tile based, and i have the grid built using grid column and row definitions and I'm successfully placing objects in various grid locations.I am currently stuck as trying to build the player object. I want a single object reference to represent the various components of the players piece.
Currently I am using a polygon to represent the piece on the grid. Eventually I want to replace this with images or something.I want to add in properties for what weapon and armor it has equipped I want properties for health Essentially in code i want something like this
dim player1 as new playerobject
player1.polygon.points = 0,0 60,30 0,60
player1.health = 100
player1.weapon = "axe"
etc
I can instantiate all this as separate variables etc, but I'd like to have a singular reference that contains all the variables, properties, objects, controls etc.I'm using vb .net in vs 2010.
I'm working in VS2010 on a visual basic application. It takes in serial port data, writes it to an access database, and then graphs the data.The data only comes in once every minute, so it's not like I'm building an oscilloscope. Right now, the chart is reading from the database using a table adapter and graphing just fine, so long as I keep the number of records in the database low.If I add too many records to the database, the chart shows a red "X" through it. I've played with changing the axes, but it is still a problem.I don't really need to graph the whole database.The twenty most recent records would suffice.How can I make a chart series with only a small subset of the database in it.Perhaps it cold be populated with a query?
View 1 RepliesI'm using VB 2008 and accessing my SQL Compact Db using the following code:
mSQLceCMD = New SqlCeCommand
mSQLceCMD.Connection = New SqlCeConnection(mStrConn)
mSQLceCMD.Connection.Open()
mSQLceCMD.CommandText = strSQL
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Currently i am using this code
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How do I really use data reader in vb.net. I'm using odbc to connect mysql and vb.net. Function I declared on a module:
Public Function form2search(ByVal drugname As String) As OdbcDataReader
cmd.CommandText = "SELECT * FROM drug WHERE Drug_name LIKE'%" & drugname & "' "
Return cmd.ExecuteReader
End Function
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I see a result, but it only loads the first item on the database. I've put this code in the text_changed event. What's the proper way of doing this? And what's wrong with the 2nd code, why is it only loading the first data. As you can see the con is the module where I declared the function. Then I created an object of it in the form.
I am using SQl data reader to get value from SQL database.Language VB.NET.After getting data into reader, i run a while loop
While reader.Read
If reader.HasRows() Then
/* Proessing of data *[code]....
Are there any examples on how to implement a datareader? I have try copying the code from MSDN but;--"Dim reader as SQLDataReader = command. ExecuteReader()"Where it is placed? As a declariton at the beggining of a form? or as as VB resource?and then how those it bind a to a dataGridView? How can I loop through each rows once is bind to use the contents of the column/row?I can perform the above function easly inside of MS Access using VBA. I have gone through various books from WROX but none of them show a clear example or the code is obsolete.
View 5 RepliesI'm switching over from PHP to vb.net. And some of the concepts are a bit different. Mainly I struggle with concepts and keywords, so it hard to look stuff up. Currently I'm creating a dashboard and needs to run a lot of different sql queries. But I see where I should be able to minimize my code. But things that I have tired don't work. Example below of two chunks of code that I should be able to put in some type of loop and increment a value for my sqlstring and textbox output.
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i have create a procedure to return data reader value, but it not return and returning null reference?
'Public Shared Sub GetData(ByVal Tablename As String, ByVal queryfield As String, ByVal Id As String, ByVal lblmsg As Label)
' Try
' Dim Cons As OleDb.OleDbConnection = DBHelper.GetConnection
' Dim Com As OleDb.OleDbCommand = New OleDb.OleDbCommand("Select * FROM [" & Tablename & "] WHERE [" & queryfield & "]=" & Val(Id), Cons)
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I'm using VB 2008 to received data from serial port (RFID Reader). below is the coding that i used. the problem's, the RFID Tag number does not display on the textboxt. [code]....
View 11 RepliesHow can i check if some value exists in the data reader
View 7 RepliesI have the first form and create 5 checkboxes which are connected to my db. Whichever checkbox is checked and the value will be inserted into the db (value: 1; data type: tinyint).And now, the second form will pull out the data base on the which checkbox is checked when the button is clicked. But for somehow i got stucked at the following code.
The first form:
Dim nValue As Boolean
If chkbox5.Checked = True Then
nValue = 1
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I have a column ("Notes") in a sqlexpress database as nvarchar(1000). It will basically hold notes. It is pulled froma richtextbox control.[code]...
View 2 RepliesI'm having a bit of trouble developing my login page! Currently i have 2 text boxes which a user can input a username and password. My form should then check whether this data relates to the data in the database and either grant or deny access.The error i'm receiving occurs at the line "If theDataReader.HasRows Then"It says 'The data reader has been used before it is assigned a value"
Here is my code:
Imports
System.Data.SqlClient
Partial
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How to populate a combo box using SQL Data Reader in DAL, BAL and UI atmosphere. Please find below my code snippets and correct me if I'm wrong anywhere in this code.
'DAL Code
Public Function PopulateComboBox() As SqlDataReader
_cnCon = New SqlConnection(_conString)
_cnCon.Open()
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What should be the UI code? Is the code specified in DAL and BAL is correct? I knoiw how to fill the combo box with values from SQL Data Reader. But I dont know how this can be done in 3 Tier application.
I have a table in my database and I want to return the rows in a data reader and retrieve them in variables. I can do that well but I can only return the last record. The reader doesn't process all the rows.
Try
Dim myconecction As String
myconecction = My.Settings.DataSource
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I'm using the following function to generate a list of users connected to a selected database. How would I change this to a single line for multiple identical results?For example: "sa (3) - MYCOMPUTER" rather than listing "sa - MYCOMPUTER" three times?
Function ConnectedUsers(ByVal SelectedDatabase As String, ByVal SelectedInstance As String)
Dim myCommand As SqlCommand
Dim dr As SqlDataReader
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I've set up a stream reader to get data from a serial file, functionality for that is already set up.
My problem is that the program seems to be missing out every other line of code in the file, which kinda defeats the point of a serial file. [code]...
how to use the VS 2010 IDE tools in a way the Microsofties didn't specifically intend. But since this is something I immediately tried without success.
I have defined a .NET 4.0 WPF Application project with a simple class that looks like this:
Public Class Class1
Public Property One As String = "OneString"
Public Property Two As String = "TwoString"
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The expected result was that "OneString" would appear next to "One" and "TwoString" next to "Two" in the running window.
The question is: Why didn't this work? What will work instead? If I put bindings in a DataTemplate, it works. Blend, with its sample data stuff, implied that this should work, but it doesn't.
I want to create a textbox which contents are validated every time the text in it changes. And an image is displayed beside the textbox if it is correct and another image shows up if its not correct. Pretty much like ajax.
Heres the method which I called from the class.
Public Sub read1()
cmd.CommandText = "SELECT * FROM testdb WHERE Name='" & name & "'"
Try
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Problem is, the method seems to be only called once. And the first image that was displayed stays the same even after inputting a data which does not exist in the database. I'm connecting this program to a mysql database using odbc.
I exported xlxs files to sql server using oledb data reader. I'm using visual studio 2005. [code]
View 3 RepliesI am trying to use the eID SDK (for using the belgian ID-card) in VB. It's supported but I can't get it to work. I have never worked with sdk's before. I did manage to get it to work in c++ in console but I really need it in visual basic. Also the VB examples that come with the sdk are made in an older version of visual studio and when my version tries to convert them they don't work. I want to use the sdk to see when a card is inserted into the reader and to read out the data. (both i got to work in c++ console).
View 2 RepliesI have a string which gets data from mssql server, reader collects data (among others also "person) SQLStr = "select * from tablename order by id desc command = New System.Data.SqlClient.SqlCommand(SQLStr, connection) reader = command.ExecuteReader() While reader.Read() ListView1SelectedItem = reader.Item("PERSON") List view contains list of persons (with IDs), including "person" from the reader. What I want is that item from reader.Item("PERSON") is selected/highlighted in the listview.
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