ApplicationFactory.HasVstoObject Method (_Worksheet)

Returns a value that indicates whether a Microsoft.Office.Tools.Excel.Worksheet host item exists for the specified Excel worksheet object.

Namespace:  Microsoft.Office.Tools.Excel
Assembly:  Microsoft.Office.Tools.Excel (in Microsoft.Office.Tools.Excel.dll)

Syntax

'Declaration
Function HasVstoObject ( _
    worksheet As _Worksheet _
) As Boolean

bool HasVstoObject(
    _Worksheet worksheet
)

Parameters

• worksheet
  Type: Microsoft.Office.Interop.Excel._Worksheet
  The native worksheet object to test. Although this parameter is of type Microsoft.Office.Interop.Excel._Worksheet, you typically pass a Microsoft.Office.Interop.Excel.Worksheet object to this method.

Return Value

Type: System.Boolean
true if a Microsoft.Office.Tools.Excel.Worksheet host item exists for the specified Microsoft.Office.Interop.Excel.Worksheet object; otherwise, false.

Remarks

You can call this method in an application-level add-in to test for the existence of managed controls that you want to persist before closing or saving the Excel worksheet.

Examples

The following code example checks whether worksheets in the current workbook have an associated host item. To use this code, run it from the ThisAddIn class in an Excel add-in project that targets the .NET Framework 4.

Private Sub Application_WorkbookBeforeSave( _
    ByVal Wb As Microsoft.Office.Interop.Excel.Workbook, _
    ByVal SaveAsUI As Boolean, _
    ByRef Cancel As Boolean) Handles Application.WorkbookBeforeSave

    If Globals.Factory.HasVstoObject(Wb) = True Then
        For Each interopSheet As Excel.Worksheet In Wb.Worksheets
            If Globals.Factory.HasVstoObject(interopSheet) = True Then
                Dim vstoSheet As Worksheet = Globals.Factory.GetVstoObject(interopSheet)
                If vstoSheet.Controls.Count > 0 Then
                    System.Windows.Forms.MessageBox.Show( _
                        "The VSTO controls are not persisted when you" _
                        + " save and close this workbook.", _
                        "Controls Persistence", _
                        System.Windows.Forms.MessageBoxButtons.OK, _
                        System.Windows.Forms.MessageBoxIcon.Warning)
                    Exit For
                End If
            End If
        Next
    End If
End Sub

void Application_WorkbookBeforeSave(
    Microsoft.Office.Interop.Excel.Workbook Wb, bool SaveAsUI, 
    ref bool Cancel)
{            
    if (Globals.Factory.HasVstoObject(Wb) == true)
    {                
        foreach (Excel.Worksheet interopSheet in Wb.Worksheets)
        {
            if (Globals.Factory.HasVstoObject(interopSheet) ==  true)
            {
                Worksheet vstoSheet = Globals.Factory.GetVstoObject(interopSheet);
                if (vstoSheet.Controls.Count > 0)
                {
                    System.Windows.Forms.MessageBox.Show(
                        "The VSTO controls are not persisted when you"
                        + " save and close this workbook.",
                        "Controls Persistence",
                        System.Windows.Forms.MessageBoxButtons.OK,
                        System.Windows.Forms.MessageBoxIcon.Warning);
                    break;
                }
            }
        }
    }
}

.NET Framework Security

• Full trust for the immediate caller. This member cannot be used by partially trusted code. For more information, see Using Libraries from Partially Trusted Code.

See Also

Reference

ApplicationFactory Interface

HasVstoObject Overload

Microsoft.Office.Tools.Excel Namespace