老师，我想问下这个修改图片的怎么保存，这段代码是修改信息的代码，图片我已经上传过了，然后进入这个修改界面，点确定的时候图片字段的内容就回被清除，只有重新添加的图片才能保存

Dim e As RequestEventArgs = args(0)

Dim wb As New WeUI

Dim bh As String = e.GetValues("id")

Dim ls As new List(Of String)

If e.PostValues.Count = 0 Then

    Dim r As DataRow = DataTables("房产信息").Find("房产编号 = \'" & bh & "\'")

    wb.AddForm("","form1","fyxg.htm?id=" & bh)

        With wb.AddInputGroup("form1","ipg7","增加图片")

        Dim lst As List(of String) = r.Lines("图片")

        With .AddUploader("图片","图片",True) \'True表示允许上传多个文件

            .AllowDelete = True \'允许删除

            .Incremental = True \'允许 重复选择文件或连续拍照

            For Each s As String In lst

                .AddImage("./images/fcs/" & s,"./images/fcs/" & s)

            Next

        End With

    End With

    With wb.AddButtonGroup("form1","btg1",True)

        .Add("btn1", "确定", "button").Attribute= "" \'调用js函数上传

    End With

    wb.AddToast("","tst1", "正在上传",1)

    wb.AddToast("","tst2", "上传成功",0)

    With wb.AddDialog("","dlg1", "提示","信息修改成功!") \'增加订单成功提示框

        .AddButton("btnYes","确定","fyxx.htm?id=" & bh ).Kind = 1

    End With

    wb.AddToast("","tst3", "上传失败",0).Icon= "warn"

    wb.AppendHTML("<script src=\'./lib/ajaxform.js\'></script>") \'引入脚本文件

    e.WriteString(wb.Build) \'生成网页

Else

    Dim nms() As String = {"区域"} \'不能为空的列名数组

    Dim dr As DataRow = DataTables("房产信息").Find("房产编号 = \'" & bh & "\'")

    For Each nm As String In nms

        If e.PostValues.ContainsKey(nm) Then

            dr(nm) = e.PostValues(nm)

        End If

    Next

    Dim i As Integer = 0

    Dim a As String 

    For Each key As String In e.Files.Keys

        For Each fln As String In e.Files(key)

            i = i + 1

            a = dr("房产编号") & "-" & i & ".jpg"

            e.SaveFile(key, fln , ProjectPath & "Attachments\\web\\images\\fcs\\" & a)

            ls.add(a)

        Next

    Next

    dr.Lines("图片") = ls

    \'保存并生成增加成功提示页面

    dr.save()

    With wb.AddMsgPage("","msgpage","增加成功", "好好学习,天天向上") \'生成成功提示页

        .AddButton("btn1","继续增加","fyxz.htm")

    End With

    e.WriteString(wb.Build)

End If

    If e.PostValues.ContainsKey("up1_deleted") Then

        MessageBox.Show(1)

    End If