主题：[求助]在狐表代码编辑器里不支持Dim app As New Excel.Application

[求助]在狐表代码编辑器里不支持Dim app As New Excel.Application吗？

            Dim app As New Excel.Application
            Dim book As Excel.Workbook = app.Workbooks.Open(ProjectPath & "Attachments\book1.xls"))
            Dim sheet As Excel.Worksheet = book.Sheets（"sheet1"）

            app.Visible = True
            sheet.PrintPreview()
            book.Close()
            app.Quit()
这段代码报错：未定义类型：Excel.Application

要怎么写代码，才能进行excel打印预览？请狐表高手指导，万分感谢！