如何在PostBack上保存FileUpload？ [英] How do I save FileUpload on PostBack?
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问题描述
无法弄清楚这一点。
这是我的代码：
<％@ 页 语言 = vb AutoEventWireup = false CodeBehind = WebForm2.aspx.vb 继承 = PDFRequesting.WebForm2 ％>
< ！DOCTYPE html >
< html xmlns = http： //www.w3.org/1999/xhtml\">
< head runat = 服务器 >
< title > < / title >
< / head >
< body >
< 表格 id = form1 runat = server >
< ajaxToolkit：ToolkitScriptManager ID = ToolkitScriptManager1 runat = server > < / ajaxToolkit：ToolkitScriptManager >
< div < span class =code-keyword>>
< asp ：标签 ID = Label1 runat = server 文字 = 标签 > < / asp：Label >
< asp：TextBox ID = TextBox1 runat = 服务器 > < / asp：TextBox >
< ajaxToolkit：AsyncFileUpload ID = AsyncFileUpload1 runat = server / >
< asp：按钮 ID = Button1 runat = server 文本 = 按钮 / >
< / div >
< / form >
< / body >
< / html >
这是我的代码背后：
Imports AjaxControlToolkit
公共 类 WebForm2
继承 System.Web.UI.Page
Dim VerifyError < span class =code-keyword> As Boolean
Pro tected Sub Page_Load（ ByVal sender As 对象， ByVal e 作为 System.EventArgs）句柄 我 .Load
' 如果第一次提交页面并且我们在FileUpload控件中有文件而在会话中没有文件
' 将值存储到SEssion对象
如果（（会话（ FileUpload23） Nothing ） AndAlso AsyncFileUpload1.HasFile）然后
会话（ FileUpload23）= AsyncFileUpload1
Label1.Text = AsyncFileUpload1.FileName
' 下次提交和会话有值，但FileUpload为空白
< span class =code-comment>' 将值从会话返回到FileUpload
ElseIf （（不（会话（ FileUpload23 ）） Nothing ） AndAlso 不 AsyncFileUpload1.HasFile）然后
AsyncFileUpload1 = CType （会话（ FileUpload23），AsyncFileUpload）
Label1.Text = AsyncFileUpload1.FileName
' 现在，当Session有文件但用户想要更改文件时，可能会有另一个问题
' 在这种情况下，我们必须更改会话对象中的文件
ElseIf AsyncFileUpload1.HasFile 然后
会话（ FileUpload23）= AsyncFileUpload1
Label1.Text = AsyncFileUpload1.FileName
结束 如果
结束 Sub
受保护的 Sub Button1_Click（发件人作为 对象，e As EventArgs）句柄 Button1.Click
如果验证（）然后
否则
Label1.Text = 错误
AsyncFileUpload1 = Session（ FileUpload23）
结束 如果
结束 Sub
< span class =code-keyword>受保护的 功能验证（）作为 布尔
验证= True
如果 TextBox1.Text = 没有 然后
验证= 错误
结束 如果
返回验证
结束 功能
结束 Class
我在网上看过这个例子但是我无法让它发挥作用。每次我点击按钮并找到错误（文本框中没有文本）页面刷新，我在AsyncFileUpload中丢失了我的文件。我尝试过使用旧的FileUpload并得到相同的结果。
我缺少什么？
谢谢
解决方案
你需要在OnUploadedComplete事件上保存文件，
参考下面的教程使用ASP.Net AJAX控件工具包AsyncFileUpload控件 [ ^ ]
和CP文章： AsyncFileUpload控件 - Ajax控件工具包中的新控件 [ ^ ]
Can't figure this out.
Here is my code:
<%@ Page Language="vb" AutoEventWireup="false" CodeBehind="WebForm2.aspx.vb" Inherits="PDFRequesting.WebForm2" %>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<ajaxToolkit:ToolkitScriptManager ID="ToolkitScriptManager1" runat="server"></ajaxToolkit:ToolkitScriptManager>
<div>
<asp:Label ID="Label1" runat="server" Text="Label"></asp:Label>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
<ajaxToolkit:AsyncFileUpload ID="AsyncFileUpload1" runat="server" />
<asp:Button ID="Button1" runat="server" Text="Button" />
</div>
</form>
</body>
</html>
And here is my code behind:
Imports AjaxControlToolkit
Public Class WebForm2
Inherits System.Web.UI.Page
Dim VerifyError As Boolean
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
'If first time page is submitted and we have file in FileUpload control but not in session
' Store the values to SEssion Object
If ((Session("FileUpload23") Is Nothing) AndAlso AsyncFileUpload1.HasFile) Then
Session("FileUpload23") = AsyncFileUpload1
Label1.Text = AsyncFileUpload1.FileName
' Next time submit and Session has values but FileUpload is Blank
' Return the values from session to FileUpload
ElseIf ((Not (Session("FileUpload23")) Is Nothing) AndAlso Not AsyncFileUpload1.HasFile) Then
AsyncFileUpload1 = CType(Session("FileUpload23"), AsyncFileUpload)
Label1.Text = AsyncFileUpload1.FileName
' Now there could be another sictution when Session has File but user want to change the file
' In this case we have to change the file in session object
ElseIf AsyncFileUpload1.HasFile Then
Session("FileUpload23") = AsyncFileUpload1
Label1.Text = AsyncFileUpload1.FileName
End If
End Sub
Protected Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
If Verify() Then
Else
Label1.Text = "Error"
AsyncFileUpload1 = Session("FileUpload23")
End If
End Sub
Protected Function Verify() As Boolean
Verify = True
If TextBox1.Text = Nothing Then
Verify = False
End If
Return Verify
End Function
End Class
I have seen this example on the net but I can't get it to work. Every time I click on the button and an error is found(No Text in the Textbox) the page refreshes and I lose my file in the AsyncFileUpload. I have tried with the old FileUpload and the I get the same results.
What am I missing?
Thank you
解决方案
you need to save file on OnUploadedComplete event,
refer below tutorial Using ASP.Net AJAX Control Toolkits AsyncFileUpload Control[^]
and CP article : AsyncFileUpload Control - New Control in Ajax Control ToolKit[^]
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