vb.net Data Gridview REfresh - vb.net

Question

i am having some issues updating a table that i have in a VB.net Windows Forms in VS 2012
i have setup the database from a service Data base, it just need a small amount of data stored locally
what i am trying to do when i create a new user it update the data grid view
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
BDate1.Format = DateTimePickerFormat.Custom
BDate1.CustomFormat = "MM/dd/yyyy"
If fname.Text <> "" And lname.Text <> "" Then
If Not cn.State = ConnectionState.Open Then
cn.Open()
End If
' cn1.Open()
If rb1.Checked Then
gen = rb1.Text.ToString
ElseIf rb2.Checked Then
gen = rb2.Text.ToString
End If
cmd.CommandText = "INSERT INTO StudentTB (FirstName,LastName,Birthday,Avatar,Gender,Grade) values('" & fname.Text & "', '" & lname.Text & "', '" & BDate1.Text & "', '" & AvtarNM.Text & "', '" & gen & "', '" & TxtGrade.Text & "')"
Dim dt As New DataTable
dt.Load(cmd.ExecuteReader())
DataGridView1.DataSource = dt
' cmd.ExecuteNonQuery()
cn.Close()
fname.Text = ""
lname.Text = ""
the issue is that i can clear the table and reload it with button but it does not show the updated values with out closing the application then reopening it, i have tried a few thing and nothing seems to refresh the connection and or update the database. any help would help.
thanks
Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click
'DataGridView1.DataSource = Nothing
Database1DataSet1.StudentTB.Clear()
' Database1DataSet1.refresh()
' Dim myda As String
' cmd.Dispose()
' cmd.Connection = cn
'Me.Database1DataSet1.Clear()
Me.StudentTBTableAdapter.Fill(Me.Database1DataSet1.StudentTB)
' 'myda = New SqlDataAdapter(cmd)
End Sub
here is the full code
Imports System
Imports System.Data
Imports System.Data.SqlClient
Imports System.Data.SqlClient.SqlDataReader
Imports System.Windows.Forms
Public Class Student
Dim cn As New SqlConnection("Data Source=(LocalDB)\v11.0;AttachDbFilename=C:\Users\Nate\documents\visual studio 2012\Projects\WindowsApplication9\WindowsApplication9\Database1.mdf;Integrated Security=True")
Dim cmd As New SqlCommand
Dim dr As SqlDataReader
Private dataAdapter As New SqlDataAdapter()
Dim gen As String
Dim bs As New BindingSource
Dim dt As New DataTable
Private Sub Student_Load(sender As Object, e As EventArgs) Handles MyBase.Load
'TODO: This line of code loads data into the 'Database1DataSet1.avTable' table. You can move, or remove it, as needed.
Me.AvTableTableAdapter.Fill(Me.Database1DataSet1.avTable)
'TODO: This line of code loads data into the 'Database1DataSet1.StudentTB' table. You can move, or remove it, as needed.
Me.StudentTBTableAdapter.Fill(Me.Database1DataSet1.StudentTB)
cmd.Connection = cn
Form1.Hide()
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
If AvTableBindingSource.Position + 1 < AvTableBindingSource.Count Then
AvTableBindingSource.MoveNext()
Button7.PerformClick()
' Otherwise, move back to the first item.
Else
AvTableBindingSource.MoveFirst()
Button7.PerformClick()
End If
' Force the form to repaint.
Me.Invalidate()
End Sub
Private Sub Button7_Click(sender As Object, e As EventArgs) Handles Button7.Click
PictureBox1.Image = System.Drawing.Bitmap.FromFile(ID.Text)
End Sub
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
BDate1.Format = DateTimePickerFormat.Custom
BDate1.CustomFormat = "MM/dd/yyyy"
If fname.Text <> "" And lname.Text <> "" Then
If Not cn.State = ConnectionState.Open Then
cn.Open()
End If
' cn1.Open()
If rb1.Checked Then
gen = rb1.Text.ToString
ElseIf rb2.Checked Then
gen = rb2.Text.ToString
End If
cmd.CommandText = "INSERT INTO StudentTB (FirstName,LastName,Birthday,Avatar,Gender,Grade) values('" & fname.Text & "', '" & lname.Text & "', '" & BDate1.Text & "', '" & AvtarNM.Text & "', '" & gen & "', '" & TxtGrade.Text & "')"
cmd.ExecuteNonQuery()
dt.Load(cmd.ExecuteReader())
bs.DataSource = dt
DataGridView1.DataSource = bs
cn.Close()
fname.Text = ""
lname.Text = ""
End If
End Sub
Private Sub genPCI()
If rb1.Checked Then
gen = rb1.Text.ToString
ElseIf rb2.Checked Then
gen = rb2.Text.ToString
End If
End Sub
Public Function ChangeFormat(ByVal dtm As DateTime, ByVal format As String) As String
Return dtm.ToString(format)
End Function
Private Sub Closestudent_Click(sender As Object, e As EventArgs) Handles Closestudent.Click
Form1.Show()
Me.Close()
End Sub
Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click
bs.EndEdit()
dataAdapter.Update(dt)
DataGridView1.DataSource = dt
' dt.Load(Command.ExecuteReader())
'Database1DataSet1.Reset()
'DataGridView1.Columns.Clear()
' DataGridView1.DataSource = Nothing
' Me.StudentTBTableAdapter.Fill(Me.Database1DataSet1.StudentTB)
' StudentTBBindingSource.ResetBindings(True)
' Database1DataSet1.refresh()
' Dim myda As String
' cmd.Dispose()
' cmd.Connection = cn
' StudentTBBindingSource.ResetBindings(False)
'Database1DataSet1.StudentTB.Clear()
' 'myda = New SqlDataAdapter(cmd)
' DataGridView1.DataSource = Database1DataSet1.StudentTB
End Sub
End Class

Answer 1

You can try like this
Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click
bs.EndEdit()
dataadapter.Update(dt)
DataGridView1.DataSource = dt
End Sub
UPDATE
or you can use bindingdatasource and delare it on your form class
Dim bs As New BindingSource
and in datagridview .. in button1_click
Dim dt As New DataTable
dt.Load(cmd.ExecuteReader())
bs.DataSource = dt
DataGridView1.DataSource = bs
So, if updated then will show after button4_click

Answer 2

Datagridview1.datasource = nothing
Dataset.reset
dim cmd as new sqldataadapter
cmd = "SELECT * FROM YOUR_DATABSE", con
con.open
cmd.fill(Dataset)
datagridview1.datasource = dataset(0).defaultview
Add these code to you button insert

Answer 3

okay after a lot of playing around this seem to fix my issue http://msdn.microsoft.com/en-us/library/fbk67b6z.aspx well all i can say it is working no idea why but it works.
Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click
Me.DataGridView1.DataSource = Me.StudentTBBindingSource
GetData("select * from StudentTB")
End Sub
Private Sub GetData(ByVal selectCommand As String)
Try
' Specify a connection string. Replace the given value with a
' valid connection string for a Northwind SQL Server sample
' database accessible to your system.
Dim connectionString As String = "Data Source=(LocalDB)\v11.0;AttachDbFilename=C:\Users\Nate\documents\visual studio 2012\Projects\WindowsApplication9\WindowsApplication9\Database1.mdf;Integrated Security=True"
' Create a new data adapter based on the specified query.
Me.dataAdapter = New SqlDataAdapter(selectCommand, connectionString)
' Create a command builder to generate SQL update, insert, and
' delete commands based on selectCommand. These are used to
' update the database.
Dim commandBuilder As New SqlCommandBuilder(Me.dataAdapter)
' Populate a new data table and bind it to the BindingSource.
Dim table As New DataTable()
table.Locale = System.Globalization.CultureInfo.InvariantCulture
Me.dataAdapter.Fill(table)
Me.StudentTBBindingSource.DataSource = table
' Resize the DataGridView columns to fit the newly loaded content.
' Me.DataGridView1.AutoResizeColumns( _
' DataGridViewAutoSizeColumnsMode.AllCellsExceptHeader)
Catch ex As SqlException
MessageBox.Show("To run this example, replace the value of the " + _
"connectionString variable with a connection string that is " + _
"valid for your system.")
End Try
End Sub

Answer 4

By Using ComboBox To Search
sql = " select * from english_language where lang=' " & ComboBox2.Text & " ' "
da = New OleDb.OleDbDataAdapter(sql, con)
Dim dt As New DataTable
da.Fill(dt)
DataGridView1.DataSource = dt
DataGridView1.Refresh()

Answer 5

Try this code to btnClear.
DataGridView.DataSource = 0
Press clear button. After that click the reload button that you coded.
I think it will reset and reload the data in data grid view.