嗯，这似乎是一个重复的老问题，但我找不到任何解决方案。我正在编写一个Web应用程序，它有许多表单都可以与AJAX一起使用，除了一个。此表单有两个查询面板和两个用于添加和编辑项目的部分。一个查询面板用于搜索现有项目，另一个用于帮助添加/编辑过程。整个表单ASP.NET代码是：
<%@ Page Title="" Language="vb" AutoEventWireup="false" MasterPageFile="~/Masters/Forms.Master" CodeBehind="EditBrands.aspx.vb" Inherits="PharmaManageWeb.EditBrands" %>
<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="server">
<title>ویرایش برندها</title>
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="PageContent" runat="server">
<asp:ScriptManagerProxy runat="server" ID="PageScriptsProxy">
</asp:ScriptManagerProxy>
<asp:Table runat="server" CssClass="formtable">
<asp:TableRow runat="server">
<asp:TableCell runat="server">
<asp:UpdatePanel runat="server" ID="AddPanel" UpdateMode="Conditional">
<ContentTemplate>
<asp:Table runat="server" ID="AddTable" CssClass="formtable">
<asp:TableRow runat="server">
<asp:TableCell runat="server" ColumnSpan="2">
افزودن برند:
</asp:TableCell>
</asp:TableRow>
<asp:TableRow runat="server">
<asp:TableCell runat="server">
نام:
</asp:TableCell>
<asp:TableCell runat="server">
<asp:TextBox runat="server" ID="AddName" CssClass="rtlinput" Width="250px"></asp:TextBox>
</asp:TableCell>
</asp:TableRow>
<asp:TableRow runat="server">
<asp:TableCell runat="server">
کد ژنریک:
</asp:TableCell>
<asp:TableCell runat="server">
<asp:TextBox runat="server" ID="AddCode" CssClass="ltrinput" Width="100px"></asp:TextBox>
</asp:TableCell>
</asp:TableRow>
<asp:TableRow runat="server">
<asp:TableCell runat="server">
نام ژنریک:
</asp:TableCell>
<asp:TableCell runat="server">
<asp:TextBox runat="server" ID="AddGName" CssClass="ltrinput" Width="250px" Enabled="false"></asp:TextBox>
</asp:TableCell>
</asp:TableRow>
<asp:TableRow runat="server">
<asp:TableCell runat="server"> </asp:TableCell>
<asp:TableCell runat="server">
<asp:Label runat="server" ID="AddErrMsg" ForeColor="Red"></asp:Label>
</asp:TableCell>
</asp:TableRow>
<asp:TableRow runat="server">
<asp:TableCell runat="server"> </asp:TableCell>
<asp:TableCell runat="server" CssClass="buttoncell">
<asp:Button runat="server" ID="SubmitAdd" Text="ارسال" OnClick="DoAdd" />
</asp:TableCell>
</asp:TableRow>
</asp:Table>
</ContentTemplate>
</asp:UpdatePanel>
<br />
<asp:UpdatePanel runat="server" ID="EditPanel" UpdateMode="Conditional">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="SubmitAdd" EventName="Click" />
</Triggers>
<ContentTemplate>
<asp:Table runat="server" ID="EditTable" CssClass="formtable">
<asp:TableRow runat="server">
<asp:TableCell runat="server" ColumnSpan="2">
ویرایش برند:
</asp:TableCell>
</asp:TableRow>
<asp:TableRow runat="server">
<asp:TableCell runat="server">
نام:
</asp:TableCell>
<asp:TableCell runat="server">
<asp:TextBox runat="server" ID="EditName" CssClass="rtlinput" Width="250px"></asp:TextBox>
</asp:TableCell>
</asp:TableRow>
<asp:TableRow runat="server">
<asp:TableCell runat="server">
کد ژنریک:
</asp:TableCell>
<asp:TableCell runat="server">
<asp:TextBox runat="server" ID="EditCode" CssClass="ltrinput" Width="100px"></asp:TextBox>
</asp:TableCell>
</asp:TableRow>
<asp:TableRow runat="server">
<asp:TableCell runat="server">
نام ژنریک:
</asp:TableCell>
<asp:TableCell runat="server">
<asp:TextBox runat="server" ID="EditGName" CssClass="ltrinput" Width="250px" Enabled="false"></asp:TextBox>
</asp:TableCell>
</asp:TableRow>
<asp:TableRow runat="server">
<asp:TableCell runat="server"> </asp:TableCell>
<asp:TableCell runat="server">
<asp:Label runat="server" ID="EditErrMsg" ForeColor="Red"></asp:Label>
</asp:TableCell>
</asp:TableRow>
<asp:TableRow runat="server">
<asp:TableCell runat="server"> </asp:TableCell>
<asp:TableCell runat="server" CssClass="buttoncell">
<asp:Button runat="server" ID="SubmitEdit" Text="ارسال" OnClick="DoEdit" Enabled="false" />
</asp:TableCell>
</asp:TableRow>
</asp:Table>
</ContentTemplate>
</asp:UpdatePanel>
<br />
<asp:UpdatePanel runat="server" ID="QueryPanel" UpdateMode="Conditional">
<ContentTemplate>
<asp:Table runat="server" ID="QueryTable" CssClass="formtable">
<asp:TableRow runat="server">
<asp:TableCell runat="server" ColumnSpan="3">
جستجوی برندها:
</asp:TableCell>
</asp:TableRow>
<asp:TableRow runat="server">
<asp:TableCell runat="server" Width="20px">
نام:
</asp:TableCell>
<asp:TableCell runat="server" Width="150px">
<asp:TextBox runat="server" ID="QueryName" CssClass="rtlinput" Width="250px"></asp:TextBox>
</asp:TableCell>
<asp:TableCell runat="server" CssClass="buttoncell">
<asp:Button runat="server" ID="SubmitQuery" Text="ارسال" OnClick="DoQuery" />
</asp:TableCell>
</asp:TableRow>
<asp:TableRow runat="server">
<asp:TableCell runat="server" ColumnSpan="3">
<asp:Label runat="server" ID="QueryErrMsg" ForeColor="Red"></asp:Label>
</asp:TableCell>
</asp:TableRow>
<asp:TableRow runat="server">
<asp:TableCell runat="server" ColumnSpan="3">
<asp:Table runat="server" ID="QueryResults" CssClass="resulttable">
</asp:Table>
</asp:TableCell>
</asp:TableRow>
</asp:Table>
</ContentTemplate>
</asp:UpdatePanel>
</asp:TableCell>
<asp:TableCell runat="server">
انتخاب کدهای ژنریک:<br />
<br />
<asp:UpdatePanel runat="server" ID="GQueryPanel" UpdateMode="Conditional">
<ContentTemplate>
<asp:Table runat="server" ID="GQueryTable" CssClass="formtable">
<asp:TableRow runat="server">
<asp:TableCell runat="server" ColumnSpan="3">
جستجوی کدها:
</asp:TableCell>
</asp:TableRow>
<asp:TableRow runat="server">
<asp:TableCell runat="server" Width="20px">
نام:
</asp:TableCell>
<asp:TableCell runat="server" Width="150px">
<asp:TextBox runat="server" ID="GQueryName" CssClass="ltrinput" Width="250px"></asp:TextBox>
</asp:TableCell>
<asp:TableCell runat="server" CssClass="buttoncell">
<asp:Button runat="server" ID="GSubmitQuery" Text="ارسال" OnClick="DoGQuery" />
</asp:TableCell>
</asp:TableRow>
<asp:TableRow runat="server">
<asp:TableCell runat="server" ColumnSpan="3">
<asp:Label runat="server" ID="GQueryErrMsg" ForeColor="Red"></asp:Label>
</asp:TableCell>
</asp:TableRow>
<asp:TableRow runat="server">
<asp:TableCell runat="server" ColumnSpan="3">
<asp:Table runat="server" ID="GQueryResults" CssClass="resulttable">
</asp:Table>
</asp:TableCell>
</asp:TableRow>
</asp:Table>
</ContentTemplate>
</asp:UpdatePanel>
</asp:TableCell>
</asp:TableRow>
</asp:Table>
</asp:Content>
背后的代码：
Public Class EditBrands
Inherits System.Web.UI.Page
Private Sub Re_CreateQueryResults(ByVal dbc As SqlConnection)
Dim qry As Base.Brands = Base.Brand.QueryBrands(dbc, Session("BrandQueryVal"))
Dim i As Integer
Dim tr As TableRow
Dim tc As TableCell
Dim bt As Button
QueryResults.Rows.Clear()
tr = New TableRow
tc = New TableCell
tc.Text = "شناسه"
tc.CssClass = "resulttableordercol"
tr.Cells.Add(tc)
tc = New TableCell
tc.Text = "نام"
tc.CssClass = "resulttabledatacol"
tr.Cells.Add(tc)
tc = New TableCell
tc.Text = "ویرایش"
tc.CssClass = "resulttableordercol"
tr.Cells.Add(tc)
QueryResults.Rows.Add(tr)
For i = 0 To qry.Count - 1
tr = New TableRow
tc = New TableCell
tc.Text = qry(i).ID
tc.CssClass = "resulttableordercol"
tr.Cells.Add(tc)
tc = New TableCell
tc.Text = qry(i).Name
tc.CssClass = "resulttabledatacol"
tr.Cells.Add(tc)
tc = New TableCell
bt = New Button
bt.Text = "ویرایش"
bt.ID = "SubmitEdit" & qry(i).ID
AddHandler bt.Click, AddressOf SubmitForEdit
tc.Controls.Add(bt)
tc.CssClass = "resulttableordercol"
tr.Cells.Add(tc)
QueryResults.Rows.Add(tr)
Next
If qry.Count = 0 Then
QueryErrMsg.Text = SystemSys.SysMan.GetSystemMessage(dbc, "NOTHINGFOUND")
QueryResults.Rows.Clear()
End If
End Sub
Private Sub Re_CreateGQueryResults(ByVal dbc As SqlConnection)
Dim qry As StatBookManager.GenericNames = StatBookManager.GenericName.QueryGenericNames(dbc, Session("GenericQueryVal3"))
Dim i As Integer
Dim tr As TableRow
Dim tc As TableCell
Dim bt As Button
GQueryResults.Rows.Clear()
tr = New TableRow
tc = New TableCell
tc.Text = "کد"
tc.CssClass = "resulttableordercol"
tr.Cells.Add(tc)
tc = New TableCell
tc.Text = "نام"
tc.CssClass = "resulttabledatacol"
tr.Cells.Add(tc)
tc = New TableCell
tc.Text = "انتخاب برای"
tc.ColumnSpan = 2
tc.CssClass = "resulttableordercol"
tr.Cells.Add(tc)
GQueryResults.Rows.Add(tr)
For i = 0 To qry.Count - 1
tr = New TableRow
tc = New TableCell
tc.Text = qry(i).Code
tc.CssClass = "resulttableordercol"
tr.Cells.Add(tc)
tc = New TableCell
tc.Text = qry(i).Name
tc.CssClass = "resulttabledatacolltr"
tr.Cells.Add(tc)
tc = New TableCell
bt = New Button
bt.Text = "افزودن"
bt.ID = "SubmitForAdd" & qry(i).ID
AddHandler bt.Click, AddressOf SubmitGForAdd
ScriptManager.GetCurrent(Me.Page).RegisterAsyncPostBackControl(bt)
tc.Controls.Add(bt)
tc.CssClass = "resulttableordercol"
tr.Cells.Add(tc)
tc = New TableCell
bt = New Button
bt.Text = "ویرایش"
bt.ID = "SubmitForEdit" & qry(i).ID
AddHandler bt.Click, AddressOf SubmitGForEdit
ScriptManager.GetCurrent(Me.Page).RegisterAsyncPostBackControl(bt)
tc.Controls.Add(bt)
tc.CssClass = "resulttableordercol"
tr.Cells.Add(tc)
GQueryResults.Rows.Add(tr)
Next
If qry.Count = 0 Then
GQueryErrMsg.Text = SystemSys.SysMan.GetSystemMessage(dbc, "NOTHINGFOUND")
GQueryResults.Rows.Clear()
Else
GQueryErrMsg.Text = ""
End If
End Sub
Protected Sub DoGQuery(ByVal sender As Object, ByVal e As EventArgs)
Dim dbc As SqlConnection = Connectivity.GetConnectionToDB(Session("DatabaseName"))
GQueryErrMsg.Text = ""
If GQueryName.Text.Trim = "" Then
GQueryErrMsg.Text = SystemSys.SysMan.GetSystemMessage(dbc, "NOGENERICNAME")
dbc.Close()
Exit Sub
End If
Session("GenericQueryVal3") = GQueryName.Text
Re_CreateGQueryResults(dbc)
dbc.Close()
End Sub
Protected Sub SubmitGForAdd(ByVal sender As Object, ByVal e As EventArgs)
MsgBox("A")
Dim dbc As SqlConnection = Connectivity.GetConnectionToDB(Session("DatabaseName"))
Dim itm As New StatBookManager.GenericName(dbc, Val(CType(sender, Button).ID.Substring(12)), StatBookManager.GenericName.IdentifyBy.ID)
AddCode.Text = itm.Code
AddGName.Text = itm.Name
AddPanel.Update()
dbc.Close()
End Sub
Protected Sub SubmitGForEdit(ByVal sender As Object, ByVal e As EventArgs)
MsgBox("E")
Dim dbc As SqlConnection = Connectivity.GetConnectionToDB(Session("DatabaseName"))
Dim itm As New StatBookManager.GenericName(dbc, Val(CType(sender, Button).ID.Substring(13)), StatBookManager.GenericName.IdentifyBy.ID)
EditCode.Text = itm.Code
EditGName.Text = itm.Name
EditPanel.Update()
dbc.Close()
End Sub
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
If Not Page.IsPostBack Then
If Session("GenericQueryVal3") IsNot Nothing Then
Session.Remove("GenericQueryVal3")
Exit Sub
End If
End If
Dim dbc As SqlConnection = Connectivity.GetConnectionToDB(Session("DatabaseName"))
If Page.IsPostBack AndAlso (Session("BrandQueryVal") IsNot Nothing) AndAlso (AJAXUtils.GetAsyncPostBackControlID(Me.Page).EndsWith("$QueryPanel")) Then
Re_CreateQueryResults(dbc)
If QueryName.Text = "" Then QueryName.Text = Session("BrandQueryVal")
End If
If Page.IsPostBack AndAlso (Session("GenericQueryVal3") IsNot Nothing) AndAlso (AJAXUtils.GetAsyncPostBackControlID(Me.Page).EndsWith("$GQueryPanel")) Then
Re_CreateGQueryResults(dbc)
If GQueryName.Text = "" Then GQueryName.Text = Session("GenericQueryVal3")
End If
dbc.Close()
End Sub
Protected Sub DoAdd(ByVal sender As Object, ByVal e As EventArgs)
Dim dbc As SqlConnection = Connectivity.GetConnectionToDB(Session("DatabaseName"))
AddErrMsg.Text = ""
If AddName.Text.Trim = "" Then
AddErrMsg.Text = SystemSys.SysMan.GetSystemMessage(dbc, "NOBRANDNAME")
dbc.Close()
Exit Sub
End If
If AddCode.Text.Trim = "" Then
AddErrMsg.Text = SystemSys.SysMan.GetSystemMessage(dbc, "NOGENERICCODE")
dbc.Close()
Exit Sub
End If
Dim itm As New Base.Brand
If Not itm.GenericName.Load(dbc, Val(AddCode.Text), StatBookManager.GenericName.IdentifyBy.Code) Then
AddErrMsg.Text = SystemSys.SysMan.GetSystemMessage(dbc, "GENERICNOTFOUND")
dbc.Close()
Exit Sub
End If
itm.Name = AddName.Text
itm.Register(dbc)
AddName.Text = ""
AddCode.Text = ""
AddGName.Text = ""
EditName.Text = ""
EditCode.Text = ""
EditGName.Text = ""
SubmitEdit.Enabled = False
dbc.Close()
End Sub
Protected Sub DoEdit(ByVal sender As Object, ByVal e As EventArgs)
Dim dbc As SqlConnection = Connectivity.GetConnectionToDB(Session("DatabaseName"))
Dim itm As New Base.Brand(dbc, Session("BrandEditID"))
EditErrMsg.Text = ""
If EditName.Text.Trim = "" Then
EditErrMsg.Text = SystemSys.SysMan.GetSystemMessage(dbc, "NOBRANDNAME")
dbc.Close()
Exit Sub
End If
If EditCode.Text.Trim = "" Then
EditErrMsg.Text = SystemSys.SysMan.GetSystemMessage(dbc, "NOGENERICCODE")
dbc.Close()
Exit Sub
End If
If Not itm.GenericName.Load(dbc, Val(EditCode.Text), StatBookManager.GenericName.IdentifyBy.Code) Then
EditErrMsg.Text = SystemSys.SysMan.GetSystemMessage(dbc, "GENERICNOTFOUND")
dbc.Close()
Exit Sub
End If
itm.Name = EditName.Text
itm.Save(dbc)
EditName.Text = ""
EditCode.Text = ""
EditGName.Text = ""
SubmitEdit.Enabled = False
Re_CreateQueryResults(dbc)
QueryPanel.Update()
dbc.Close()
End Sub
Protected Sub DoQuery(ByVal sender As Object, ByVal e As EventArgs)
Dim dbc As SqlConnection = Connectivity.GetConnectionToDB(Session("DatabaseName"))
QueryErrMsg.Text = ""
If QueryName.Text.Trim = "" Then
QueryErrMsg.Text = SystemSys.SysMan.GetSystemMessage(dbc, "NOBRANDNAME")
dbc.Close()
Exit Sub
End If
Session("BrandQueryVal") = QueryName.Text
Re_CreateQueryResults(dbc)
dbc.Close()
End Sub
Protected Sub SubmitForEdit(ByVal sender As Object, ByVal e As EventArgs)
Dim dbc As SqlConnection = Connectivity.GetConnectionToDB(Session("DatabaseName"))
Dim itm As New Base.Brand(dbc, Val(CType(sender, Button).ID.Substring(10)))
Session("BrandEditID") = itm.ID
EditName.Text = itm.Name
EditCode.Text = itm.GenericName.Code
EditGName.Text = itm.GenericName.Name
SubmitEdit.Enabled = True
EditPanel.Update()
Re_CreateQueryResults(dbc)
dbc.Close()
End Sub
Private Sub EditBrands_PreRender(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.PreRender
If Page.IsPostBack AndAlso (Session("GenericQueryVal3") IsNot Nothing) Then
Dim dbc As SqlConnection = Connectivity.GetConnectionToDB(Session("DatabaseName"))
Re_CreateGQueryResults(dbc)
dbc.Close()
End If
End Sub
End Class
动态添加/编辑按钮添加在Re_CreateGQueryResults（）子例程中。如你所见，我添加了两个MsgBox语句，说＆＃34; A＆＃34;单击动态添加按钮时，＆＃34; E＆＃34;单击动态编辑按钮时。问题就出在这里：当我点击一个动态添加按钮时，MsgBox（＆＃34; A＆＃34;）可以工作，但只适用于第一个！进一步点击不会导致任何进一步的消息框（并且不会对AddName，AddCode，AddGName的内容进行任何更改），并且其他动态编辑按钮也不会起作用，直到会话到期（例如，在ASP.NET Development Server上重建）。首次点击动态编辑按钮时会出现类似的行为（没有其他消息框，既不是通过编辑按钮也不是添加按钮）。
问题出在哪里？
修改
我通过将页面加载代码移动到页面初始化事件并将每个动态添加和编辑按钮的AsyncPostBackTriggers添加到GQueryPanel的触发器集合来解决了这个问题（尽管Microsoft明确表示这不会起作用;但是为我工作！）。现在，还有另一个问题：SubmitGForAdd（）和SubmitGForEdit（）子例程没有按预期工作。在此之前，首次单击时，AddCode和AddGName文本框将获取其值，并且这些值将显示在浏览器上。但现在，它们总是空着的。我测试了代码运行和itm变量是否正确加载了它的数据。我相信这些文本框取其价值，但它们在浏览器的路上消失了！任何人都可以解释原因吗？
答案 0 :(得分：0)
我通过将页面加载代码移动到页面初始化事件并将每个动态添加和编辑按钮的AsyncPostBackTriggers添加到GQueryPanel的触发器集合来解决了这个问题（尽管Microsoft明确表示这不会起作用;但是为我工作！）。这是确切的代码差异：
In：Re_CreateGQueryResults（）
...
Dim trg as AsyncPostBackTrigger
...
For i = 0 To qry.Count - 1
...
AddHandler bt.Click, AddressOf SubmitGForAdd
trg = New AsyncPostBackTrigger
trg.ControlID = bt.ID
trg.EventName = "Click"
GQueryPanel.Triggers.Add(trg)
...
AddHandler bt.Click, AddressOf SubmitGForEdit
trg = New AsyncPostBackTrigger
trg.ControlID = bt.ID
trg.EventName = "Click"
GQueryPanel.Triggers.Add(trg)
...
和
Protected Sub Page_Init(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Init
If Not Page.IsPostBack Then
If Session("GenericQueryVal3") IsNot Nothing Then
Session.Remove("GenericQueryVal3")
Exit Sub
End If
End If
Dim dbc As SqlConnection = Connectivity.GetConnectionToDB(Session("DatabaseName"))
If Page.IsPostBack AndAlso (Session("BrandQueryVal") IsNot Nothing) AndAlso (AJAXUtils.GetAsyncPostBackControlID(Me.Page).EndsWith("$QueryPanel")) Then
Re_CreateQueryResults(dbc)
If QueryName.Text = "" Then QueryName.Text = Session("BrandQueryVal")
End If
If Page.IsPostBack AndAlso (Session("GenericQueryVal3") IsNot Nothing) AndAlso (AJAXUtils.GetAsyncPostBackControlID(Me.Page).EndsWith("$GQueryPanel")) Then
Re_CreateGQueryResults(dbc)
If GQueryName.Text = "" Then GQueryName.Text = Session("GenericQueryVal3")
End If
dbc.Close()
End Sub
此致