有没有办法在嵌套 if 循环中使用“FOR”语句？答案

【问题标题】：Is there a way to have a "FOR" statement within a nested-if loop?有没有办法在嵌套 if 循环中使用“FOR”语句？
【发布时间】：2020-01-06 14:52:45
【问题描述】：

如果工作簿中的工作表与用户输入的值匹配，我将尝试删除它。如果该值不存在，则显示错误消息。有没有比我目前拥有的更好的方法来做到这一点？

最初，我尝试了一个带有多个 if 语句的嵌套 if 循环来获得我所取得的结果，但这没有奏效。下面的代码是我得到的，但它仍然有一些错误。例如，当满足第一个 FOR 条件时，两个 FOR 语句都会出现消息框（这是不正确的）。

Dim ws As Worksheet

Private Sub cmdDeleteProj_Click()
'
'Remove project sheet after project has been completed
'

'Show error message if user input field is blank
If txtRemProjNum.Value = "" Then
    MsgBox "Input valid project number to continue.", vbExclamation, "Required Field Left Blank"
    uf_RemProj.txtRemProjNum.SetFocus
End If

'Delete user defined project sheet if it exists
On Error Resume Next
For Each ws In ActiveWorkbook.Worksheets
    If ws.Name = txtRemProjNum Then
        Application.DisplayAlerts = False
        ws.Delete
        Application.DisplayAlerts = True
        MsgBox "Project removed from inventory tracker."
    End If
Next ws

'Show error message if project does not exist
On Error Resume Next
For Each ws In ActiveWorkbook.Worksheets
    If txtRemProjNum.Value <> "" And ws.Name <> txtRemProjNum Then
        MsgBox "Project number not found." & vbNewLine & "" & vbNewLine & "Input valid project number.", vbCritical, "Out of Range"
        uf_RemProj.txtRemProjNum.Text = ""
        uf_RemProj.txtRemProjNum.SetFocus
    End If
Next ws

End Sub

如果工作表存在，我希望将其删除，但无法使 if 语句和 FOR 循环工作。

【问题讨论】：

标签： excel vba for-loop nested-loops

【解决方案1】：

试一试，如有任何问题，请告诉我。我没有过多评论，因为代码流应该是不言自明的。

Option Explicit

Dim ws As Worksheet

Private Sub cmdDeleteProj_Click()

    'Remove project sheet after project has been completed

    'Show error message if user input field is blank
    If txtRemProjNum.Value = "" Then
        MsgBox "Input valid project number to continue.", vbExclamation, "Required Field Left Blank"
        uf_RemProj.txtRemProjNum.SetFocus
        Exit Sub
    End If

    Dim projectFound As Boolean

    'Delete user defined project sheet if it exists
    For Each ws In ThisWorkbook.Worksheets
        If ws.Name = txtRemProjNum Then
            Application.DisplayAlerts = False
            ws.Delete
            Application.DisplayAlerts = True
            MsgBox "Project removed from inventory tracker."
            projectFound = True
            Exit For
        End If
    Next ws

    If Not projectFound Then
        MsgBox "Project number not found." & vbNewLine & "" & vbNewLine & "Input valid project number.", vbCritical, "Out of Range"
        uf_RemProj.txtRemProjNum.Text = ""
        uf_RemProj.txtRemProjNum.SetFocus
    End If

End Sub

【讨论】：

【解决方案2】：

我认为您看到这两条消息是因为工作表在第一个循环中而不是在第二个循环中。为什么不只循环一次并使用elseif 语句

For Each ws In ActiveWorkbook.Worksheets
    If ws.Name = txtRemProjNum Then
        Application.DisplayAlerts = False
        ws.Delete
        Application.DisplayAlerts = True
        MsgBox "Project removed from inventory tracker."
    ElseIf
        txtRemProjNum.Value <> "" And ws.Name <> txtRemProjNum Then
        MsgBox "Project number not found." & vbNewLine & "" & vbNewLine & "Input 
                valid project number.", vbCritical, "Out of Range"
        uf_RemProj.txtRemProjNum.Text = ""
        uf_RemProj.txtRemProjNum.SetFocus
    End If
Next ws

【讨论】：