vba怎么用if函数来进行计算？

我从家里学了自动加入公式的代码，因为数据很多，难住了。特请大家帮忙!

对数据格式都不够了解啊！
Private Sub Worksheet_Change(ByVal Target As Range)
Dim h As Integer
Dim i As Integer
With Target
h = .Row
If h <= 6 Then Exit Sub
If .Column = 1 Then
For i = .Row To .Row + .Rows.Count - 1
If Cells(i, 1) = "" Then
Range(Cells(i, 2), Cells(i, 26)).ClearContents
Else
Cells(i, 10).Value = "=iif(month(cells(i,3)>=9,date(year(cells(i,3))+7,9,1),date(year(cells(i,3))+6,9,1)"
End If
Next
End If
End With
End Sub

你好，好像还是没有用。什么原因，望告知!

用了vba 就没必要用太多公式了吧。。。

请您看看我的附件，如果要得出J列的数据，该如何做？

工作表J列先设置日期格式

Private Sub Worksheet_Change(ByVal Target As Range)
Dim h As Integer
Dim i As Integer
Dim x As Integer

With Sheets("sheet1")
x = .[a:a].Find("*", , , , , xlPrevious).Row
End With

With Target
h = .Row
If h <= 6 Then Exit Sub
If .Column = 1 Then
For i = .Row To x
If Cells(i, 1) = "" Then
Range(Cells(i, 2), Cells(i, 26)).ClearContents
Else
Cells(i, 10) = "=if(month(R" & i & "C3)>=9,date(year(R" & i & "C3)+7,9,1),date(year(R" & i & "C3)+6,9,1))"
End If
Next
End If
End With
End Sub