dnn URLControl 上传文件重名 如何不覆盖？

问题如题.  别人也有提过，LOOK：

overwrite files 

I have a column in UDT, type "download".  So, when I upload file with the same name as existing file, it overwrites the old one.

How can I avoid this? I don't want users to change uploaded files in that way, because I need to see the old version of those files, like an archive.

覆盖了多恐怖啊，之前的文件就不存在了。  意味着可能重要信息丢失。

回复： http://local.dotnetnuke.com/Community/Forums/tabid/795/forumid/56/postid/271990/scope/posts/Default.aspx

 You can't avoid this. UDT uses the URL control of the DNN core, it is the way it handles it.

---

Stefan Cullmann

 

解决方案：

1.添加一个属性

Public Property IsOverWrite() As Boolean
            Get
                If Not ViewState("IsOverWrite") Is Nothing AndAlso Trim(Convert.ToString(ViewState("IsOverWrite"))) <> "" Then
                    IsOverWrite = CType(ViewState("IsOverWrite"), Boolean)
                Else
                    IsOverWrite = False
                End If
            End Get
            Set(ByVal Value As Boolean)
                ViewState("IsOverWrite") = Value
            End Set
        End Property

2.判断一下是否覆盖

 修改文件 Controls\URLControl.vb  中的事件cmdSave_Click

 

Private Sub cmdSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdSave.Click

            cmdUpload.Visible = False

            ' if no file is selected exit
            If txtFile.PostedFile.FileName = "" Then
                Exit Sub
            End If

            Dim ParentFolderName As String
            If PortalSettings.ActiveTab.ParentId = PortalSettings.SuperTabId Then
                ParentFolderName = Common.Globals.HostMapPath
            Else
                ParentFolderName = PortalSettings.HomeDirectoryMapPath
            End If
            ParentFolderName += cboFolders.SelectedItem.Value

            'change by xy 20100407   if the same fileName ,set a new fileName
            Dim strExtension As String = Replace(Path.GetExtension(txtFile.PostedFile.FileName), ".", "")
            Dim rootPath As String = ParentFolderName.Replace("/", "\")
            Dim sourceFileName As String = txtFile.PostedFile.FileName
            Dim strFileName As String = sourceFileName.Substring(sourceFileName.LastIndexOf("\") + 1)
            sourceFileName = rootPath & strFileName
            If FileFilter <> "" And InStr("," & FileFilter.ToLower, "," & strExtension.ToLower) = 0 Then
                ' trying to upload a file not allowed for current filter
                lblMessage.Text = String.Format(Localization.GetString("UploadError", Me.LocalResourceFile), FileFilter, strExtension)
            Else
                If IsOverWrite = True Then
                    lblMessage.Text = FileSystemUtils.UploadFile(ParentFolderName.Replace("/", "\"), txtFile.PostedFile, False)
                Else
                    If File.Exists(sourceFileName) = True Then
                        Dim _now As String = System.DateTime.Now.ToString("yyyyMMddHHmmss", System.Globalization.CultureInfo.InvariantCulture)
                        Dim extension As String = "." + strExtension
                        strFileName = strFileName.Replace(extension, "") & _now & extension
                        sourceFileName = rootPath & strFileName
                        lblMessage.Text = FileSystemUtils.UploadFile(ParentFolderName.Replace("/", "\"), txtFile.PostedFile, sourceFileName, False)
                    Else
                        lblMessage.Text = FileSystemUtils.UploadFile(ParentFolderName.Replace("/", "\"), txtFile.PostedFile, False)
                    End If
                End If
            End If

            If lblMessage.Text = String.Empty Then
                cboFiles.Visible = True
                cmdUpload.Visible = ShowUpLoad
                txtFile.Visible = False
                cmdSave.Visible = False
                cmdCancel.Visible = False

                Dim Root As New DirectoryInfo(ParentFolderName)
                cboFiles.Items.Clear()
                cboFiles.DataSource = GetFileList(False)
                cboFiles.DataBind()

                'modify by xy
                'Dim FileName As String = txtFile.PostedFile.FileName.Substring(txtFile.PostedFile.FileName.LastIndexOf("\") + 1)
                If Not cboFiles.Items.FindByText(strFileName) Is Nothing Then
                    cboFiles.Items.FindByText(strFileName).Selected = True
                End If

                If cboFiles.SelectedIndex >= 0 Then
                    ViewState("LastFileName") = cboFiles.SelectedValue
                Else
                    ViewState("LastFileName") = ""
                End If
            End If

            _doRenderTypeControls = False 'Must not render on this postback
            _doRenderTypes = False
            _doChangeURL = False
            _doReloadFolders = False
            _doReloadFiles = False
        End Sub

 3.前台控件即可灵活配置是否覆盖

 <Portal:url id="ctlAttachment" runat="server" IsOverWrite="False" UrlType="F" />

 

 Well Done!