Public Overloads Function IsExcelFile( _
   ByVal fileName As String, _
   ByRef workbookType As ExcelWorkbookType _
) As Boolean

Dim instance As FpSpread
Dim fileName As String
Dim workbookType As ExcelWorkbookType
Dim value As Boolean
 
value = instance.IsExcelFile(fileName, workbookType)

public bool IsExcelFile( 
   string fileName,
   ref ExcelWorkbookType workbookType
)

string s = "c:\\test.xls";
bool b = fpSpread1.IsExcelFile(s, FarPoint.Excel.ExcelWorkbookType.BIFF);
if (b)
{
fpSpread1.OpenExcel(s);
}

Dim s As String = "c:\test.xls"
Dim b As Boolean = FpSpread1.IsExcelFile(s, FarPoint.Excel.ExcelWorkbookType.BIFF)
If b Then
FpSpread1.OpenExcel(s)
End If