Bonjour,
Je ne me souviens plus comment supprimer un contrôle par le code, quand le contrôle en question a était créer par le code.
Sur ce code aux lignes 51 à 54 j'ai:
Warning Variable 'labelCorner' is used before it has been assigned a value. A null reference exception could result at runtime.
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58 Private Sub AddCorners(ByVal sender As Object, ByVal e As System.EventArgs) Handles TrackPage.Enter Dim numberOfCorner As Integer Dim latestNumberOfCorner As Integer Dim labelCorner As Label Dim labelSpeed As Label Dim cornerName_tbox As TextBox Dim cornerSpeed_tbox As TextBox numberOfCorner = CInt(Me.NumberOfCorners_tbox.Value) If numberOfCorner - latestNumberOfCorner > 1 Then For i = latestNumberOfCorner + 1 To numberOfCorner Step 1 labelCorner = New Label With labelCorner .Text = "Corner " & i.ToString .Font = New System.Drawing.Font("ab", 8, FontStyle.Bold) .Size = New System.Drawing.Size(70, 15) .Location = New System.Drawing.Point(17, 84 + (25 * i - 1)) End With labelSpeed = New Label With labelSpeed .Text = "[km/h]" .Font = New System.Drawing.Font("ab", 8, FontStyle.Bold) .Location = New System.Drawing.Point(362, 84 + (25 * i - 1)) End With cornerName_tbox = New TextBox With cornerName_tbox .Name = "Corner" & i.ToString & "_tbox" .Size = New System.Drawing.Size(200, 20) .Location = New System.Drawing.Point(90, 83 + (25 * i - 1)) End With cornerSpeed_tbox = New TextBox With cornerSpeed_tbox .Name = "Speed" & i.ToString & "_tbox" .Size = New System.Drawing.Size(60, 20) .Location = New System.Drawing.Point(296, 83 + (25 * i - 1)) End With TrackPage.Controls.Add(labelCorner) TrackPage.Controls.Add(labelSpeed) TrackPage.Controls.Add(cornerName_tbox) TrackPage.Controls.Add(cornerSpeed_tbox) Next ElseIf numberOfCorner - latestNumberOfCorner < 1 Then TrackPage.Controls.Remove(labelCorner) TrackPage.Controls.Remove(labelSpeed) TrackPage.Controls.Remove(cornerName_tbox) TrackPage.Controls.Remove(cornerSpeed_tbox) End If latestNumberOfCorner = numberOfCorner End Sub
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