• VB.net删除节点,数据库,文件


    Private Sub mnuDel_Click()
    '删除节点
    Dim sKey As String
    'Dim sFile As String
    Dim oFS As FileSystemObject
    Dim sPathFile As String
    Dim sIndex As String
    Dim sFlag As String
    Set oFS = New FileSystemObject
    On Error Resume Next
    If MsgBox("确定要删除此类别[" & TreeView1.SelectedItem.Text & "]", vbYesNo, "静态信息") = vbYes Then
        sKey = TreeView1.SelectedItem.Key
        sIndex = TreeView1.SelectedItem.Index
    '    sFile = sContentPath & sKey & "*" & ".htm"
    '    sFlag = Check(sIndex)
        sFlag = Len(sKey) - 1
        If RemoveInfo(sKey) Then
            TreeView1.Nodes.Remove TreeView1.SelectedItem.Index
            sPathFile = Dir(sContentPath)
            While (sPathFile <> "")
                If Mid(sPathFile, 2, sFlag) = Right(sKey, Len(sKey) - 1) Then
    '                oFS.DeleteFile sPathFile, True
                    Kill sContentPath & sPathFile
                End If
                sPathFile = Dir
            Wend
            If TreeView1.SelectedItem.Children = 0 Then
               TreeView1.SelectedItem.Image = "closed"
            End If
        End If
    End If
    End Sub

     补充函数Dir用法,Dir(Path)遍历指定目录下的所有文件,第一次返回第一个文件,如果不想重复遍历,下一次调用时不要加参数。

    函数Kill用法,Kill(Path&file)删除绝对路径下的文件,不可以缺少目录(或者只写文件名)。

    While....Wend循环,类似于C语言的While循环。

    If嵌套调用,If...Then...Elseif..Then....EndIf。

    Private Function RemoveInfo(sSearch As String) As Boolean
    Dim sSQL As String
    Dim objDataAccess As clsDataAccess
    RemoveInfo = False
    On Error GoTo errHandle
    '    sSQL = "Delete From BCCB_Info Where Id=" & Right(sSearch, Len(sSearch) - 1)
        sSQL = "Delete From BCCB_Info Where Id like '" & Right(sSearch, Len(sSearch) - 1) & "%'"
        Set objDataAccess = New clsDataAccess
        If objDataAccess.ExecSQL(sSQL) Then RemoveInfo = True
       
        Set objDataAccess = Nothing
    Exit Function
    errHandle:
        RemoveInfo = False
        Call WriteLog(DEBUG_LEVEL, "frmBCCBInfo.RemoveInfo Error" & err.Description)
        Set objDataAccess = Nothing
    End Function

    补充语法:

    操作数据库过程:

    声明一个连接,建立或者实例化一个连接,准备好SQL数据库语句,执行语句,释放连接(适用于Access)。

    声明一个连接,建立或者实例化一个连接,声明一个数据集,建立或者实例化一个数据集,准备SQL数据库语句,执行数据库语句,释放数据集,释放连接(适用于ADO.RecordSet)。

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  • 原文地址:https://www.cnblogs.com/gyc19920704/p/5259264.html
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