“对象变量或With块变量未设置”的异常

“对象变量或With块变量未设置”的错误
Public Function FindSheet(sheetName As String) As Worksheet

  Dim name As String
  For I = 0 To ThisWorkbook.Sheets.Count - 1
  name = ThisWorkbook.Sheets(I + 1).name
  If name = sheetName Then
  FindSheet = ThisWorkbook.Sheets(I)
  Exit Function
  End If
  Next I
  FindSheet = ThisWorkbook.Sheets(1) '运行到这一句时出现 “对象变量或With块变量未设置”的错误
End Function

------解决方案--------------------------------------------------------

VB code

Public Function FindSheet(sheetName As String) As Worksheet  Dim name As String  For I = 0 To ThisWorkbook.Sheets.Count - 1    name = ThisWorkbook.Sheets(I + 1).name    If name = sheetName Then        Set FindSheet = ThisWorkbook.Sheets(I)        Exit Function    End If  Next I  Set FindSheet = ThisWorkbook.Sheets(1) '运行到这一句时出现 “对象变量或With块变量未设置”的错误End Function