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• WARNING #6022

WARNING #6022

The CommonDialog CancelError property is not supported in Visual Basic .NET.

Description 

The property CommonDialog.CancelError is not currently supported by VBUC, nevertheless it is possible get a similar behavior or functionality by using .NET properties. 

Recommendations 

Understand how the CommonDialog.CancelError property is used in the VB6 source code and apply a manual change in order to emulate the behavior in the .NET platform. 

In .NET, the CommonDialog.ShowDialog() method shows the Dialog and after the dialog is closed, returns the information of the Dialog button that was pressed by the user. This returning value must be compared against the members of the System.Windows.Forms.DialogResult Enumeration 

Sample VB6 

Private Sub cmdColour_Click()
    On Error GoTo errhandler
    CommonDialog1.CancelError = True

    ' Display the Colour dialog box
    CommonDialog1.ShowColor
    ' Set the forms background colour to the one selected
    Me.BackColor = CommonDialog1.Color
    Exit Sub
errhandler:
    Select Case Err
    Case 32755 ' Dialog Canceled
         MsgBox "You canceled the dialog box"
    Case Else
         MsgBox "Unexpected error. Err " & Err & " : " & Error
    End Select
End Sub

Target VB.NET 

PrivateSub cmdColour_Click(ByVal eventSender AsObject, ByVal eventArgs As EventArgs) Handles cmdColour.Click 
OnErrorGoTo errhandler 
'UPGRADE_WARNING: (6022) The CommonDialog CancelError property is not supported in Visual Basic .NET. 
CommonDialog1.CancelError = True 
' Display the Colour dialog box 
CommonDialog1Color.ShowDialog()
' Set the forms background colour to the one selected 
Me.BackColor = CommonDialog1Color.Color 
ExitSub 
errhandler:
SelectCase Information.Err().Number 
Case 32755 ' Dialog Canceled 
MessageBox.Show("You canceled the dialog box", Application.ProductName) 
CaseElse 
MessageBox.Show("Unexpected error. Err " & Information.Err().Number & " : " & Conversion.ErrorToString(), Application.ProductName) 
EndSelect 
EndSub 

Expected VB.NET 

PrivateSub cmdColour_Click(ByVal eventSender AsObject, ByVal eventArgs As EventArgs) Handles cmdColour.Click
OnErrorGoTo errhandler
'UPGRADE_WARNING: (6022) The CommonDialog CancelError property is not supported in Visual Basic .NET.
'CommonDialog1.CancelError = True
' Display the Colour dialog box
'CommonDialog1Color.ShowDialog()
If (System.Windows.Forms.DialogResult.Cancel <> CommonDialog1Color.ShowDialog()) Then
' Set the forms background colour to the one selected
Me.BackColor = CommonDialog1Color.Color
ExitSub
EndIf
errhandler:
SelectCase Information.Err().Number
Case 32755 ' Dialog Canceled
MessageBox.Show("You canceled the dialog box", Application.ProductName)
CaseElse
MessageBox.Show("Unexpected error. Err " & Information.Err().Number & " : " & Conversion.ErrorToString(), Application.ProductName)
EndSelect
EndSub

Target C# 

privatevoid cmdColour_Click( Object eventSender, EventArgs eventArgs)
{
try
{
//UPGRADE_WARNING: (6022) The CommonDialog CancelError property is not supported in Visual Basic .NET.
CommonDialog1.CancelError = true;
// Display the Colour dialog box
CommonDialog1Color.ShowDialog();
// Set the forms background colour to the one selected
this.BackColor = CommonDialog1Color.Color;
}
catch
{
//UPGRADE_WARNING: (1041) Err.Number has a new behavior.
switch(Information.Err().Number)
{
case 32755 : // Dialog Canceled
MessageBox.Show("You canceled the dialog box", Application.ProductName);
break;
default:
//UPGRADE_WARNING: (1041) Err.Number has a new behavior.
MessageBox.Show("Unexpected error. Err " + Information.Err().Number.ToString() + " : " + Conversion.ErrorToString(), Application.ProductName);
break;
}
}
}

Expected C# 

privatevoid cmdColour_Click( Object eventSender, EventArgs eventArgs)
{
try
{
//UPGRADE_WARNING: (6022) The CommonDialog CancelError property is not supported in Visual Basic .NET.
//CommonDialog1.CancelError = true;
// Display the Colour dialog box
//CommonDialog1Color.ShowDialog();
if (System.Windows.Forms.DialogResult.Cancel != CommonDialog1Color.ShowDialog())
{
// Set the forms background colour to the one selected
this.BackColor = CommonDialog1Color.Color;
}
}
catch
{
//UPGRADE_WARNING: (1041) Err.Number has a new behavior.
switch(Information.Err().Number)
{
case 32755 : // Dialog Canceled
MessageBox.Show("You canceled the dialog box", Application.ProductName);
break;
default:
//UPGRADE_WARNING: (1041) Err.Number has a new behavior.
MessageBox.Show("Unexpected error. Err " + Information.Err().Number.ToString() + " : " + Conversion.ErrorToString(), Application.ProductName);
break;
}
}
}

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