将CreateObject（＆＃34; PowerPoint.Application＆＃34;）结果赋予变量时键入不匹配错误

Question

我尝试从Excel模块中的VBA代码运行Power Point应用程序。我首先选择了Microsoft Power Point对象库。但是当我运行下面的代码时，我得到了一个

  

错误13（类型不匹配）

符合CreateObject函数。我注意到同样的情况是试图定义其他变量Ppp，Spp和Chrt。你知道这个错误的原因是什么吗？

    Sub Test()
      Dim App As PowerPoint.Application
      Dim Ppp As PowerPoint.Presentation
      Dim Spp As PowerPoint.Slide
      Dim Chrt As PowerPoint.Chart

      'Opens Power Point application
      Set App = CreateObject("PowerPoint.Application")
      'Set App = New PowerPoint.Application
      'Makes the application visible (if necessary)
      App.Visible = True
      'Opens existing power point document
      Set Ppp = App.Presentations.Open("C:\Gap\Charts.pptx")
      'Sets the second slide
      Set Spp = Ppp.Slides(2)
      'Sets the chart named "EmbededChart"
      Set Chrt = Spp.Shapes("EmbededChart").Chart
    End Sub