Display SQL query result on VB form - vb.net

I am facing a problem displaying the result of my "select *" query on the form . Here is my code:
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
myconnection = New SqlConnection("server=PARTH-PC\SQLEXPRESS;uid=sa;pwd=parth;database=college")
myconnection.Open()
mycommand = New SqlCommand("SELECT * from [demo3]",myconnection)
Dim mySqlDataAdapter As New SqlDataAdapter(mycommand)
Dim mydsStudent As New DataSet()
DataGridView2.DataSource = mydsStudent
Me.Controls.Add(DataGridView2)
ra = mycommand.ExecuteNonQuery()
MessageBox.Show("Data displayed" & ra)
myconnection.Close()
End Sub
But when I write this code and run my form I am not able to see any records present in my database tables being displayed on my form. I have inserted a DataGridView on my form . What changes should I do to my code ? Can Anyone help me ?
Thanks in advance

When you are working with a DataAdapter, you need to call the Fill() method for it to fill a DataSet/DataTable. After you initialize the DataSet, make this call:
mySqlDataAdapter.Fill(mydsStudent)
Also, take out your ExecuteNonQuery() call.
EDIT: Try something like this.
Dim myconn As New SqlConnection(yourConnectionStringHere)
Dim myTable As New DataTable()
Dim myCmd As New SqlCommand()
myCmd.Connection = myconn
myCmd.CommandText = "select * from demo3"
Dim myAdapater As New SqlDataAdapter(myCmd)
myAdapter.Fill(myTable)
DataGridView2.DataSource = myTable

Related

How to feed results of SQL statement into a GridView, not the SQL statement itself?

This has got to be close, but it's been a long day and I'm tired now so I can;t really see what the problem is. Basically, I have a table in SQL Server with 2 columns; one has the names of reports and the other has some SQL Scripts that I want to pass into a GridView, based on what a user selects from a ListBox. Here is my code.
Imports System.Data.SqlClient
Public Class Form1
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Try
Dim sqlConn As New SqlClient.SqlConnection("Data Source=EXCEL-PC\SQLEXPRESS;Initial Catalog=Test;Integrated Security=True")
sqlConn.Open()
Dim cmd As New SqlClient.SqlCommand("Select ReportName From [Table_1] order by ReportName", sqlConn)
Dim dsColumns As New DataSet
Dim daAdapter As New SqlClient.SqlDataAdapter(cmd)
daAdapter.Fill(dsColumns)
If dsColumns.Tables(0).Rows.Count > 0 Then
ListBox1.Items.Clear()
For i As Integer = 0 To dsColumns.Tables(0).Rows.Count - 1
ListBox1.Items.Add(dsColumns.Tables(0).Rows(i)(0).ToString())
Next
End If
Catch ex As Exception
End Try
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim connetionString As String
Dim SqlStr As String
Dim connection As SqlConnection
Dim adapter As SqlDataAdapter
Dim ds As New DataSet
Dim myItem As String
connetionString = "Data Source=EXCEL-PC\SQLEXPRESS;Initial Catalog=Test;Integrated Security=True"
connection = New SqlConnection(connetionString)
'Dim iIndex As Integer = ListBox1.SelectedIndex
myItem = ListBox1.SelectedItem
SqlStr = "select SqlScript from [Table_1] Where ReportName = '" & myItem & "'"
Try
connection.Open()
adapter = New SqlDataAdapter(SqlStr, connection)
adapter.Fill(ds)
connection.Close()
DataGridView1.DataSource = ds.Tables(0)
Catch ex As Exception
MsgBox(ex.ToString)
End Try
End Sub
End Class
I guess the problem is passing the SQL to the GridView. When I select the first Item, I see this in my GridView.
SELECT [OrderID]
,[CustomerID]
,[EmployeeID]
,[OrderDate]
,[RequiredDate]
,[ShippedDate]
,[ShipVia]
,[Freight]
,[ShipName]
,[ShipAddress]
,[ShipCity]
,[ShipRegion]
,[ShipPostalCode]
,[ShipCountry]
FROM [Test].[dbo].[Orders]
That's pretty close, but I want to get that SQL fed into the GridView, and get the results of the SQL displayed in the GridView, not eh SQL statement itself.
This is what I see now.
I want to see something more like this.
Finally, I am curious to know of the GridView can be made dynamic, so if I stretch out the window the GridView shows more columns. Now, if I stretch out the form window, the GridView stays static.
You need to actually run the retrieved Sql statement:
sqlstr = "select SqlScript from [Table_1] Where ReportName = '" & myItem & "'"
Try
connection.Open()
Dim cmd As New SqlCommand(sqlstr, connection)
Dim sqlstr_report As String = CStr(cmd.ExecuteScalar())
cmd.Dispose()
adapter = New SqlDataAdapter(sqlstr_report, connection)
adapter.Fill(ds)
connection.Close()
DataGridView1.DataSource = ds.Tables(0)
Use the .Anchor property of the DataGridView to make it resize with the form

Filtering Data within a DataGridView in VB.NET

How would I add a filtration function to my program so when I begin typing into a text box, it filters the results in the DataGridView? Just to clarify, this code loads a linked Access database into the DataGridView on form load and allows me to add, remove and update the data contained with in.
I'm relatively new to Visual Basic and I have ran out of ideas in regards to what to in order to get it to work. Thank you in advance for any help provided!
Imports System.Data.OleDb
Public Class frmDatabase
Dim con As New OleDbConnection
Dim ds As New DataSet
Dim dt As New DataTable
Dim da As New OleDbDataAdapter
Private Sub frmDatabase_Load(sender As Object, e As EventArgs) Handles MyBase.Load
con.ConnectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\Users\Joe\Documents\Visual Studio 2012\Projects\school database viewer\school database viewer\dbSchoolDatabase.mdb"
con.Open()
ds.Tables.Add(dt)
da = New OleDbDataAdapter("Select * from tableStudentDetails", con)
Dim cb = New OleDbCommandBuilder(da)
cb.QuotePrefix = "["
cb.QuoteSuffix = "]"
da.Fill(dt)
dgvStudentDetails.DataSource = dt.DefaultView
con.Close()
End Sub
Private Sub cmdSave_Click_1(sender As Object, e As EventArgs) Handles cmdSave.Click
da.Update(dt)
End Sub

VB.Net OleDBConnection code to update access database from DataGridView

I have a simple userform with a DataGridView and I would like to use OleDB code to update the accdb database based on any entries made in the gridview. The load button works fine, but the save button produces this error:
Update requires a valid UpdateCommand when passed DataRow collection with modified rows.
Here is my code:
Imports System.Data.OleDb
Public Class Form1
Dim myConString As String
Dim con As OleDbConnection = New OleDbConnection
Dim Dadapter As OleDbDataAdapter
Dim DSet As DataSet
Dim DSet2 As DataSet
Dim ConCMD As OleDb.OleDbCommand
Private Sub load_btn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles load_btn.Click
myConString = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=\\Psmccsfs01\snd\PRODUCTION\Licensed\Reporting\FTO Adjustment Tools\FTO_Log_DB.accdb;"
con.ConnectionString = myConString
con.Open()
Dadapter = New OleDbDataAdapter("select * from FTO_Log", con)
DSet = New DataSet
Dadapter.Fill(DSet, "FTO_Log")
DataGridView1.DataSource = DSet.Tables("FTO_Log")
con.Close()
End Sub
Private Sub save_btn_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles save_btn.Click
Using con = New OleDbConnection(myConString)
con.Open()
Dadapter.Update(DSet, "FTO_Log")
End Using
End Sub
End Class
dataAdpater.UpdateCommand = new SqlCommand(
"UPDATE Categories SET CategoryName = #CategoryName " +
"WHERE CategoryID = #CategoryID", connection);
notice the typo in the code above, straight from the msdn site ;p
short and simple: http://msdn.microsoft.com/en-us/library/33y2221y%28v=vs.110%29.aspx

Issue with Comobox on DataGridView

I am using VB.NET to pull some data from an SQL database into a Datagridview.
I then want the user to be able to modify the information and save it back to the database, which I have working fine.
What I need to be able to do now is to restrict the values, but way of a combobox for the field Tarrif.
I have configured a DataSource called Tarrif1 and I am using the below code.
I have a couple of issues/questions.
Firstly the dropdown shows a single value of "System.Data.DataViewManagerListItemTypeDescriptor" not the Tarrif1 values.
Secondly, I now have 2 columns on my datatable called Tarrif, the original database one and the one I have added - How can I get the ComboBox to right back to the appropriate Tarrif database field.
Here is my code:
Imports System.Data.SqlClient
Imports System.Data.Common
Public Class ViewCustomersForm
Dim ds As DataSet = New DataSet()
Dim connStr As String = "server=barry-laptop\SQLEXPRESS; database=BillingReferenceData; integrated security=yes"
Dim sql As String = "SELECT * FROM Customers"
Dim conn As SqlConnection = New SqlConnection(connStr)
Dim comm As SqlCommand = New SqlCommand(Sql, conn)
Dim dataadapter As SqlDataAdapter = New SqlDataAdapter(comm)
Private Sub ViewCustomersForm_Load(sender As Object, e As EventArgs) Handles MyBase.Load
'---open the connection and fill the dataset---
conn.Open()
dataadapter.Fill(ds, "Customers_table")
conn.Close()
DataGridView1.DataSource = ds
DataGridView1.DataMember = "Customers_table"
'---create a combobox column---
Dim comboBoxCol As New DataGridViewComboBoxColumn
'---set the header---
comboBoxCol.HeaderText = "Tarrifs"
'---data bind it---
comboBoxCol.DataSource = Tarrifs1
'comboBoxCol.DisplayMember = "Tarrif" // when I add these rows the new Tarrif column is not visible
'comboBoxCol.ValueMember = "Tarrif" // when I add these rows the new Tarrif column is not visible
'---add a combobox column to the DataGridView control---
DataGridView1.Columns.Add(comboBoxCol)
End Sub
Private Sub Button_Click_1(sender As Object, e As EventArgs) Handles Button1.Click
Dim sqlCmdBuilder As New SqlCommandBuilder(dataadapter)
sqlCmdBuilder.GetUpdateCommand()
dataadapter.Update(ds.Tables("Customers_table"))
End Sub
Private Sub DataGridView1_CellContentClick(sender As Object, e As DataGridViewCellEventArgs) Handles DataGridView1.CellContentClick
End Sub
End Class
Hope that makes sense. Any help greatly appreciated.
A few things in this code:
dataadapter.Fill(ds, "Customers_table")
conn.Close()
DataGridView1.DataSource = ds
DataGridView1.DataMember = "Customers_table"
'---create a combobox column---
Dim comboBoxCol As New DataGridViewComboBoxColumn
'---set the header---
comboBoxCol.HeaderText = "Tarrifs"
'---data bind it---
comboBoxCol.DataSource = Tarrifs1
First, I'm not sure what happens whenever the code attempts to fill a DataSet that already has data in it. In my code, I never assume, so I always reinitialize it each time unless I need it:
ds = new DataSet()
Next, you are setting the DataSource for comboBoxCol as Tarrifs1, but I do not see that defined anywhere. You might want to look into that.
Finally, about the SQL: Dim sql As String = "SELECT * FROM Customers" I don't know what columns are in your Customers table. Is Tarrif an actual column?
I figured half my issue out.
I configured a second data connection to pull the Tarrif drop down from the Tarrifs table and display this as part of the customer data table.
My outstanding issues now, is that I need to write the select Tarrif value back to the Customers table.
All the other updated values save, just not sure how to write the Tarrif dropdown back to my SQL table
Here is my latest code.
Imports System.Data.SqlClient
Imports System.Data.Common
Public Class ViewCustomersForm
Dim ds As DataSet = New DataSet()
Dim connStr As String = "server=barry-laptop\SQLEXPRESS; database=BillingReferenceData; integrated security=yes"
Dim sql As String = "SELECT [Customer ID] ,[Customer Name] ,[Address] ,[City] ,[County] ,[Post Code] FROM [BillingReferenceData].[dbo].[Customers]"
Dim conn As SqlConnection = New SqlConnection(connStr)
Dim comm As SqlCommand = New SqlCommand(Sql, conn)
Dim dataadapter As SqlDataAdapter = New SqlDataAdapter(comm)
Dim con As New System.Data.SqlClient.SqlConnection("server=barry-laptop\SQLEXPRESS; database=Test; integrated security=yes")
Dim strSQL As String = "SELECT * FROM Tarrifs"
Dim da As New System.Data.SqlClient.SqlDataAdapter(strSQL, con)
Private Sub ViewCustomersForm_Load(sender As Object, e As EventArgs) Handles MyBase.Load
'---open the connection and fill the dataset---
conn.Open()
dataadapter.Fill(ds, "Customers_table")
conn.Close()
DataGridView1.DataSource = ds
DataGridView1.DataMember = "Customers_table"
'---create a combobox column---
Dim comboBoxCol As New DataGridViewComboBoxColumn
'---set the header---
comboBoxCol.HeaderText = "Tarrifs"
'---data bind it---
da.Fill(ds, "Tarrifs")
comboBoxCol.DataSource = ds.Tables("Tarrifs")
comboBoxCol.DisplayMember = "Tarrif"
comboBoxCol.ValueMember = "Tarrif"
'---add a combobox column to the DataGridView control---
DataGridView1.Columns.Add(comboBoxCol)
End Sub
Private Sub Button_Click_1(sender As Object, e As EventArgs) Handles Button1.Click
Dim sqlCmdBuilder As New SqlCommandBuilder(dataadapter)
sqlCmdBuilder.GetUpdateCommand()
dataadapter.Update(ds.Tables("Customers_table"))
dataadapter.Update(ds.Tables("Tarrifs"))
End Sub
Private Sub DataGridView1_CellContentClick(sender As Object, e As DataGridViewCellEventArgs) Handles DataGridView1.CellContentClick
End Sub
End Class

How To Populate a DropDown List From a DataSet?

I am trying to populate an ASP dropdown list in vb.net with the results from a stored procedure returned in a data set. I was wondering if anyone knew the vb.net code to populate the dropdown list?
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles Me.Load
Dim connString As String = "Server=MYCOMPUTER\SQLEXPRESS;Database=scales;Trusted_Connection=True"
Dim myConn As New SqlConnection(connString)
myConn.Open()
Dim da As New SqlDataAdapter("select scaleName from scales", myConn)
Dim dt As New DataTable
da.Fill(dt)
ComboBox1.DisplayMember = "scaleName"
ComboBox1.DataSource = dt
myConn.Close()
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles Me.Load
IF Not IsPostback then
PopulateDropdown()
End IF
End Sub
Private Sub PopulateDropDown()
Dim connString As String = "Server=MYCOMPUTER\SQLEXPRESS;Database=scales;Trusted_Connection=True"
Dim myConn As New SqlConnection(connString)
myConn.Open()
Dim da As New SqlDataAdapter("select ScaleId, scaleName from scales", myConn)
Dim dt As New DataTable
da.Fill(dt)
Me.ComboBox1.DataTextField = "scaleName "
Me.ComboBox1.DataValueField = "ScaleId"
Me.ComboBox1.DataSource = dt
Me.ComboBox1.DataSourceID = String.Empty
Me.ComboBox1.DataBind()
myConn.Close()
End Sub
In order to show the data in the DropDownList control, you can use the following Code. To use the results of a Stored Procedure, you need to create the SELECT command:
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles Me.Load
If Not Page.IsPostBack Then
Dim dt As New DataTable
Dim connString As String = "Server=MYCOMPUTER\SQLEXPRESS;Database=scales;Trusted_Connection=True"
Using myConn As New SqlConnection(connString)
myConn.Open()
Using cmd = myConn.CreateCommand()
cmd.CommandType = CommandType.StoredProcedure
cmd.CommandText = "dbo.uspMyStoredProc"
cmd.Parameters.AddWithValue("#MyInputParam", 123)
Using da As New SqlDataAdapter(cmd)
da.Fill(dt)
End Using
End Using
End Using
ComboBox1.DisplayMember = "scaleName"
ComboBox1.DataSource = dt
ComboBox1.DataBind()
End If
' ...
End Sub
I've adjusted the following things:
Usually you only need to bind the data on the initial request. Therefore, the if statement at the beginning checks the IsPostBack property.
In order to close and dispose the connection and the data datapter reliably, I've added some using statements.
In order to access the stored procedure, I've created a SqlCommand and set the CommandType to StoredProcedure. The CommandText is set to the name of the Stored Procedure. In the sample, I've also added a parameter named MyInputParam that is sent to the Stored Procedure.