Buongiorno !
sto utilizzando VS 2008 e in particolare l'oggetto del datagridview; devo utilizzarlo successivamente con un database;
Sto sfruttando l'esempio di MSDN e con il seguente codice :
--->
Imports System
Imports System.Drawing
Imports System.Windows.Forms

Public Class Form1
Inherits System.Windows.Forms.Form

Private buttonPanel As New Panel
Private WithEvents songsDataGridView As New DataGridView
Private WithEvents addNewRowButton As New Button
Private WithEvents deleteRowButton As New Button

Private Sub Form1_Load(ByVal sender As System.Object, _
ByVal e As System.EventArgs) Handles MyBase.Load

SetupLayout()
SetupDataGridView()
PopulateDataGridView()

End Sub

Private Sub songsDataGridView_CellFormatting(ByVal sender As Object, _
ByVal e As System.Windows.Forms.DataGridViewCellFormattingEventArgs) _
Handles songsDataGridView.CellFormatting

If Me.songsDataGridView.Columns(e.ColumnIndex).Name = _
"Release Date" Then

If e IsNot Nothing Then
If e.Value IsNot Nothing Then
Try
e.Value = DateTime.Parse(e.Value.ToString()) _
.ToLongDateString()
e.FormattingApplied = True
Catch ex As FormatException
Console.WriteLine("{0} is not a valid date.", e.Value.ToString())
End Try
End If
End If

End If

End Sub

Private Sub addNewRowButton_Click(ByVal sender As Object, _
ByVal e As EventArgs) Handles addNewRowButton.Click

Me.songsDataGridView.Rows.Add()

End Sub

Private Sub deleteRowButton_Click(ByVal sender As Object, _
ByVal e As EventArgs) Handles deleteRowButton.Click

If Me.songsDataGridView.SelectedRows.Count > 0 AndAlso _
Not Me.songsDataGridView.SelectedRows(0).Index = _
Me.songsDataGridView.Rows.Count - 1 Then

Me.songsDataGridView.Rows.RemoveAt( _
Me.songsDataGridView.SelectedRows(0).Index)

End If

End Sub

Private Sub SetupLayout()

Me.Size = New Size(600, 500)

With addNewRowButton
.Text = "Add Row"
.Location = New Point(10, 10)
End With

With deleteRowButton
.Text = "Delete Row"
.Location = New Point(100, 10)
End With

With buttonPanel
.Controls.Add(addNewRowButton)
.Controls.Add(deleteRowButton)
.Height = 50
.Dock = DockStyle.Bottom
End With

Me.Controls.Add(Me.buttonPanel)

End Sub

Private Sub SetupDataGridView()

Me.Controls.Add(songsDataGridView)

songsDataGridView.ColumnCount = 5
With songsDataGridView.ColumnHeadersDefaultCellStyle
.BackColor = Color.Navy
.ForeColor = Color.White
.Font = New Font(songsDataGridView.Font, FontStyle.Bold)
End With

With songsDataGridView
.Name = "songsDataGridView"
.Location = New Point(8, 8)
.Size = New Size(500, 250)
.AutoSizeRowsMode = _
DataGridViewAutoSizeRowsMode.DisplayedCellsExceptHeaders
.ColumnHeadersBorderStyle = DataGridViewHeaderBorderStyle.Single
.CellBorderStyle = DataGridViewCellBorderStyle.Single
.GridColor = Color.Black
.RowHeadersVisible = False

.Columns(0).Name = "Release Date"
.Columns(1).Name = "Track"
.Columns(2).Name = "Title"
.Columns(3).Name = "Artist"
.Columns(4).Name = "Album"
.Columns(4).DefaultCellStyle.Font = _
New Font(Me.songsDataGridView.DefaultCellStyle.Font, FontStyle.Italic)

.SelectionMode = DataGridViewSelectionMode.FullRowSelect
.MultiSelect = False
.Dock = DockStyle.Fill
End With

End Sub

Private Sub PopulateDataGridView()

Dim row0 As String() = {"11/22/1968", "29", "Revolution 9", _
"Beatles", "The Beatles [White Album]"}
Dim row1 As String() = {"1960", "6", "Fools Rush In", _
"Frank Sinatra", "Nice 'N' Easy"}
Dim row2 As String() = {"11/11/1971", "1", "One of These Days", _
"Pink Floyd", "Meddle"}
Dim row3 As String() = {"1988", "7", "Where Is My Mind?", _
"Pixies", "Surfer Rosa"}
Dim row4 As String() = {"5/1981", "9", "Can't Find My Mind", _
"Cramps", "Psychedelic Jungle"}
Dim row5 As String() = {"6/10/2003", "13", _
"Scatterbrain. (As Dead As Leaves.)", _
"Radiohead", "Hail to the Thief"}
Dim row6 As String() = {"6/30/1992", "3", "Dress", "P J Harvey", "Dry"}

With Me.songsDataGridView.Rows
.Add(row0)
.Add(row1)
.Add(row2)
.Add(row3)
.Add(row4)
.Add(row5)
.Add(row6)
End With

With Me.songsDataGridView
.Columns(0).DisplayIndex = 3
.Columns(1).DisplayIndex = 4
.Columns(2).DisplayIndex = 0
.Columns(3).DisplayIndex = 1
.Columns(4).DisplayIndex = 2
End With

End Sub


<STAThreadAttribute()> _
Public Shared Sub Main()
Application.EnableVisualStyles()
Application.Run(New Form1())
End Sub

End Class

-------------->
voglio che questo componente venga visualizzato in una form al momento che mi serve passando poi (successivamente dei parametri), pertanto, ho in inserito quasi tutto il codice nella classe component1 (appositamente creata) nel seguente modo:

Imports System
Imports System.Drawing
Imports System.Windows.Forms
Imports WProva2


<Microsoft.VisualBasic.ComClass()> <System.Serializable()> Public Class Component1

Public buttonPanel As New Panel
Public WithEvents songsDataGridView As New DataGridView
Public WithEvents addNewRowButton As New Button
Public WithEvents deleteRowButton As New Button

Sub accetta()

SetupLayout()
SetupDataGridView()
PopulateDataGridView()
End Sub

Private Sub songsDataGridView_CellFormatting(ByVal sender As Object, _
ByVal e As System.Windows.Forms.DataGridViewCellFormattingEventArgs) _
Handles songsDataGridView.CellFormatting
' Inherits System.Windows.Forms.Form
If Me.songsDataGridView.Columns(e.ColumnIndex).Name = _
"Release Date" Then

If e IsNot Nothing Then
If e.Value IsNot Nothing Then
Try
e.Value = DateTime.Parse(e.Value.ToString()) _
.ToLongDateString()
e.FormattingApplied = True
Catch ex As FormatException
Console.WriteLine("{0} is not a valid date.", e.Value.ToString())
End Try
End If
End If

End If

End Sub

Private Sub addNewRowButton_Click(ByVal sender As Object, _
ByVal e As EventArgs) Handles addNewRowButton.Click

Me.songsDataGridView.Rows.Add()

End Sub

Private Sub deleteRowButton_Click(ByVal sender As Object, _
ByVal e As EventArgs) Handles deleteRowButton.Click

If Me.songsDataGridView.SelectedRows.Count > 0 AndAlso _
Not Me.songsDataGridView.SelectedRows(0).Index = _
Me.songsDataGridView.Rows.Count - 1 Then

Me.songsDataGridView.Rows.RemoveAt( _
Me.songsDataGridView.SelectedRows(0).Index)

End If

End Sub

Private Sub SetupLayout()

DataGridView1.Size = New Size(600, 500)

With addNewRowButton
.Text = "Add Row"
.Location = New Point(10, 10)
End With

With deleteRowButton
.Text = "Delete Row"
.Location = New Point(100, 10)
End With

With buttonPanel
.Controls.Add(addNewRowButton)
.Controls.Add(deleteRowButton)
.Height = 50
.Dock = DockStyle.Bottom
End With

DataGridView1.Controls.Add(Me.buttonPanel)

End Sub

Private Sub SetupDataGridView()

DataGridView1.Controls.Add(songsDataGridView)

songsDataGridView.ColumnCount = 5
With songsDataGridView.ColumnHeadersDefaultCellStyle
.BackColor = Color.Navy
.ForeColor = Color.White
.Font = New Font(songsDataGridView.Font, FontStyle.Bold)
End With

With songsDataGridView
.Name = "songsDataGridView"
.Location = New Point(8, 8)
.Size = New Size(500, 250)
.AutoSizeRowsMode = _
DataGridViewAutoSizeRowsMode.DisplayedCellsExceptHeaders
.ColumnHeadersBorderStyle = DataGridViewHeaderBorderStyle.Single
.CellBorderStyle = DataGridViewCellBorderStyle.Single
.GridColor = Color.Black
.RowHeadersVisible = False

.Columns(0).Name = "Release Date"
.Columns(1).Name = "Track"
.Columns(2).Name = "Title"
.Columns(3).Name = "Artist"
.Columns(4).Name = "Album"
.Columns(4).DefaultCellStyle.Font = _
New Font(Me.songsDataGridView.DefaultCellStyle.Font, FontStyle.Italic)

.SelectionMode = DataGridViewSelectionMode.FullRowSelect
.MultiSelect = False
.Dock = DockStyle.Fill
End With

End Sub

Private Sub PopulateDataGridView()

Dim row0 As String() = {"11/22/1968", "29", "Revolution 9", _
"Beatles", "The Beatles [White Album]"}
Dim row1 As String() = {"1960", "6", "Fools Rush In", _
"Frank Sinatra", "Nice 'N' Easy"}
Dim row2 As String() = {"11/11/1971", "1", "One of These Days", _
"Pink Floyd", "Meddle"}
Dim row3 As String() = {"1988", "7", "Where Is My Mind?", _
"Pixies", "Surfer Rosa"}
Dim row4 As String() = {"5/1981", "9", "Can't Find My Mind", _
"Cramps", "Psychedelic Jungle"}
Dim row5 As String() = {"6/10/2003", "13", _
"Scatterbrain. (As Dead As Leaves.)", _
"Radiohead", "Hail to the Thief"}
Dim row6 As String() = {"6/30/1992", "3", "Dress", "P J Harvey", "Dry"}

With Me.songsDataGridView.Rows
.Add(row0)
.Add(row1)
.Add(row2)
.Add(row3)
.Add(row4)
.Add(row5)
.Add(row6)
End With

With Me.songsDataGridView
.Columns(0).DisplayIndex = 3
.Columns(1).DisplayIndex = 4
.Columns(2).DisplayIndex = 0
.Columns(3).DisplayIndex = 1
.Columns(4).DisplayIndex = 2
End With

End Sub
<STAThreadAttribute()> _
Public Shared Sub Main()
Application.EnableVisualStyles()
Application.Run(New WProva2.Form1)
End Sub


End Class


---->
e nella form ho il seguente codice:

Imports System
Imports System.Drawing
Imports System.Windows.Forms

Public Class Form1

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

Dim comp As New Component1
comp.accetta()

End Sub


End Class
------>

purtroppo sebbenne mi manda tutto in esecuzione, non capisco come mai, la Form è tutta bianca e non esegue nulla ! (scusate ma non sono molto esperto)
Come mai ? Mi potete aiutare ? Come posso fare diversamente ?
Altra cosa : dove posso trovare altri esempi con l'oggetto Datagridview ?
Mi postate eventualmente il link ?
Grazie.

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Modificato da navigatore65 il 26 ottobre 2008 09.55 -