asp.net - 将 session 变量传递给 SQLDataSource 时出错

Question

我正在尝试运行 项目.aspx . Admin.apsx，当单击“查看配置文件”按钮时，应该创建一个 session “project_id”，因此两个 SQLDataSources 从 Session(“project_id”) 中获取 project_id 值。

我收到此错误:



项目.aspx

<%@ Page Title="" Language="VB" MasterPageFile="~/MasterPage.master" AutoEventWireup="false" CodeFile="Project.aspx.vb" Inherits="Project" %>


<%@ Register assembly="System.Web.DataVisualization, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" namespace="System.Web.UI.DataVisualization.Charting" tagprefix="asp" %>



<asp:Content ID="Content3" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server">
    <div id="project-image"><asp:Image ID="Image1" runat="server" Height="124px" Width="93px" />
        <asp:FormView ID="frmViewProject" runat="server" DataKeyNames="project_id" DataSourceID="SqlDataSource1" HorizontalAlign="Justify">
            <EditItemTemplate>
                project_id:
                <asp:Label ID="project_idLabel1" runat="server" Text='<%# Eval("project_id") %>' />
                <br />
                project_type:
                <asp:TextBox ID="project_typeTextBox" runat="server" Text='<%# Bind("project_type") %>' />
                <br />
                project_start:
                <asp:TextBox ID="project_startTextBox" runat="server" Text='<%# Bind("project_start") %>' />
                <br />
                project_finish:
                <asp:TextBox ID="project_finishTextBox" runat="server" Text='<%# Bind("project_finish") %>' />
                <br />
                project_duration:
                <asp:TextBox ID="project_durationTextBox" runat="server" Text='<%# Bind("project_duration") %>' />
                <br />
                project_budget:
                <asp:TextBox ID="project_budgetTextBox" runat="server" Text='<%# Bind("project_budget") %>' />
                <br />
                project_cost:
                <asp:TextBox ID="project_costTextBox" runat="server" Text='<%# Bind("project_cost") %>' />
                <br />
                project_name:
                <asp:TextBox ID="project_nameTextBox" runat="server" Text='<%# Bind("project_name") %>' />
                <br />
                <asp:LinkButton ID="UpdateButton" runat="server" CausesValidation="True" CommandName="Update" Text="Update" />
                &nbsp;<asp:LinkButton ID="UpdateCancelButton" runat="server" CausesValidation="False" CommandName="Cancel" Text="Cancel" />
            </EditItemTemplate>
            <EditRowStyle BorderStyle="Solid" Font-Bold="False" Font-Names="Verdana" Font-Overline="False" Font-Size="Small" HorizontalAlign="Right" VerticalAlign="Middle" />
            <InsertItemTemplate>
                project_type:
                <asp:TextBox ID="project_typeTextBox" runat="server" Text='<%# Bind("project_type") %>' />
                <br />
                project_start:
                <asp:TextBox ID="project_startTextBox" runat="server" Text='<%# Bind("project_start") %>' />
                <br />
                project_finish:
                <asp:TextBox ID="project_finishTextBox" runat="server" Text='<%# Bind("project_finish") %>' />
                <br />
                project_duration:
                <asp:TextBox ID="project_durationTextBox" runat="server" Text='<%# Bind("project_duration") %>' />
                <br />
                project_budget:
                <asp:TextBox ID="project_budgetTextBox" runat="server" Text='<%# Bind("project_budget") %>' />
                <br />
                project_cost:
                <asp:TextBox ID="project_costTextBox" runat="server" Text='<%# Bind("project_cost") %>' />
                <br />
                project_name:
                <asp:TextBox ID="project_nameTextBox" runat="server" Text='<%# Bind("project_name") %>' />
                <br />
                <asp:LinkButton ID="InsertButton" runat="server" CausesValidation="True" CommandName="Insert" Text="Insert" />
                &nbsp;<asp:LinkButton ID="InsertCancelButton" runat="server" CausesValidation="False" CommandName="Cancel" Text="Cancel" />
            </InsertItemTemplate>
            <InsertRowStyle HorizontalAlign="Center" VerticalAlign="Middle" />
            <ItemTemplate>
                project_id:
                <asp:Label ID="project_idLabel" runat="server" Text='<%# Eval("project_id") %>' />
                <br />
                project_type:
                <asp:Label ID="project_typeLabel" runat="server" Text='<%# Bind("project_type") %>' />
                <br />
                project_start:
                <asp:Label ID="project_startLabel" runat="server" Text='<%# Bind("project_start") %>' />
                <br />
                project_finish:
                <asp:Label ID="project_finishLabel" runat="server" Text='<%# Bind("project_finish") %>' />
                <br />
                project_duration:
                <asp:Label ID="project_durationLabel" runat="server" Text='<%# Bind("project_duration") %>' />
                <br />
                project_budget:
                <asp:Label ID="project_budgetLabel" runat="server" Text='<%# Bind("project_budget") %>' />
                <br />
                project_cost:
                <asp:Label ID="project_costLabel" runat="server" Text='<%# Bind("project_cost") %>' />
                <br />
                project_name:
                <asp:Label ID="project_nameLabel" runat="server" Text='<%# Bind("project_name") %>' />
                <br />

            </ItemTemplate>
            <RowStyle BorderStyle="None" HorizontalAlign="Left" VerticalAlign="Middle" />
        </asp:FormView>
        <asp:Chart ID="chrtComplete" runat="server" DataMember="DefaultView" DataSourceID="SqlDataSource2" EnableViewState="True">
            <series>
                <asp:Series ChartType="Pie" Legend="Completed" Name="Series1" XValueMember="project_start" YValueMembers="project_finish">
                </asp:Series>
            </series>
            <chartareas>
                <asp:ChartArea Name="ChartArea1">
                </asp:ChartArea>
            </chartareas>
            <Legends>
                <asp:Legend LegendStyle="Row" Name="Completed">
                </asp:Legend>
            </Legends>
            <Titles>
                <asp:Title Name="Project Completion">
                </asp:Title>
            </Titles>
        </asp:Chart>
        <asp:SqlDataSource ID="SqlDataSource2" runat="server" ConnectionString="<%$ ConnectionStrings:ConnStringDb1 %>" SelectCommand="SELECT [project_start], [project_finish] FROM [projects] WHERE ([project_id] = @project_id)">
            <SelectParameters>
                <asp:SessionParameter Name="project_id" SessionField="project_id" Type="Int32" />
            </SelectParameters>
        </asp:SqlDataSource>
    </div>
    <div id="project-info">
        <asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:ConnStringDb1 %>" SelectCommand="SELECT [project_id], [project_type], [project_start], [project_finish], [project_duration], [project_budget], [project_cost], [project_name] FROM [projects] WHERE ([project_id] = @project_id)">
            <SelectParameters>
                <asp:SessionParameter Name="project_id" SessionField="project_id" Type="Int32" />
            </SelectParameters>
        </asp:SqlDataSource>
    </div>
&nbsp;
    <br />
</asp:Content>

管理.aspx

Imports System.Data.SqlClient

Partial Class Admin
    Inherits System.Web.UI.Page

    Protected Sub btnSearchUser_Click(sender As Object, e As EventArgs) Handles btnSearchUser.Click

        Dim conn As New SqlConnection("Data Source=BRIAN-PC\SQLEXPRESS;Initial Catalog=master_db;Integrated Security=True")
        Dim searchComm As String = "SELECT username FROM users WHERE CONTAINS (username, @username)"

        Dim searchSQL As New SqlCommand

        conn.Open()

        searchSQL = New SqlCommand(searchComm, conn)
        searchSQL.Parameters.AddWithValue("@username", txtUserSearch.Text)

        Dim datareader As SqlDataReader = searchSQL.ExecuteReader()

        While datareader.Read

            lstUsers.Items.Add(datareader.Item("username"))

        End While



        datareader.Close()
        conn.Close()

    End Sub

    Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load

    End Sub

    Protected Sub DropDownList1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles drpProjects.SelectedIndexChanged



        Dim conn As New SqlConnection("Data Source=BRIAN-PC\SQLEXPRESS;Initial Catalog=master_db;Integrated Security=True")
        Dim sqlComm As String = "SELECT project_name FROM projects WHERE project_name=@projectname"
        Dim sqlProjname As New SqlCommand

        conn.Open()

        sqlProjname = New SqlCommand(sqlComm, conn)
        sqlProjname.Parameters.AddWithValue("@projectname", drpProjects.SelectedItem.Text)
        Dim datareader As SqlDataReader = sqlProjname.ExecuteReader()
        datareader.Read()


        If datareader.HasRows Then

            lblProjName.Text = datareader("project_name").ToString()
        End If

        datareader.Close()
        conn.Close()

        lblProjName.Visible = True
        grdProjDetails.Visible = True







    End Sub

    Protected Sub btnManageProj_Click(sender As Object, e As EventArgs) Handles btnManageProj.Click

        MultiView1.SetActiveView(View2)


    End Sub

    Protected Sub btnProjSettings_Click(sender As Object, e As EventArgs) Handles btnProjSettings.Click

        Dim conn2 As New SqlConnection("Data Source=BRIAN-PC\SQLEXPRESS;Initial Catalog=master_db;Integrated Security=True")
        Dim sqlComm2 As String = "SELECT project_id FROM projects WHERE project_name=@projectname"
        Dim sqlProjID As New SqlCommand

        conn2.Open()

        sqlProjID = New SqlCommand(sqlComm2, conn2)
        sqlProjID.Parameters.AddWithValue("@projectname", drpProjects.SelectedItem.Text)
        Dim datareader As SqlDataReader = sqlProjID.ExecuteReader()
        datareader.Read()


        If datareader.HasRows Then

            Dim UserID As String
            UserID = datareader("project_id").ToString

            Session("project_id") = UserID
            Server.Transfer("Project.aspx", True)

        End If

        datareader.Close()
        conn2.Close()



    End Sub
End Class

MasterPage.aspx

<%@ Master Language="VB" CodeFile="MasterPage.master.vb" Inherits="MasterPage" %>
<%@ Import Namespace="System.Data.SqlClient" %>
<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
<script runat="server">



    Protected Sub Page_Load(sender As Object, e As EventArgs)

        If Session("userid") = Nothing Then
            txtLoginUser.Visible = True
            txtLoginPass.Visible = True

        Else


            Dim conn As New SqlConnection("Data Source=BRIAN-PC\SQLEXPRESS;Initial Catalog=master_db;Integrated Security=True")
            Dim useridComm As String = "SELECT name, surname FROM users WHERE user_id=@userid"
            Dim sqlUserID As New SqlCommand

            conn.Open()

            Dim userid As String = Session("userid")

            sqlUserID = New SqlCommand(useridComm, conn)
            sqlUserID.Parameters.AddWithValue("@userid", userid)
            Dim datareader As SqlDataReader = sqlUserID.ExecuteReader()
            If datareader.HasRows Then

                FormsAuthentication.RedirectFromLoginPage(datareader("user_id"), True)
                lblLoggedIn.Text = datareader("name").ToString() & " " & datareader("surname").ToString()

            End If
            datareader.Close()
            conn.Close()

        End If
    End Sub

   Protected Sub Button1_Click(sender As Object, e As EventArgs)

        Dim loginSQL As New SqlCommand
        Dim loginComm As String

        Dim CommonFunctions As New CommonFunctions()
        Dim dec_pass As String = CommonFunctions.EncryptPassword(txtLoginPass.Text.Trim)

        Dim conn As New SqlConnection("Data Source=BRIAN-PC\SQLEXPRESS;Initial Catalog=master_db;Integrated Security=True")


        loginComm = "SELECT user_id FROM users WHERE username=@username and password=@password"

        conn.Open()


        loginSQL = New SqlCommand(loginComm, conn)
        loginSQL.Parameters.AddWithValue("@username", txtLoginUser.Text.ToString)
        loginSQL.Parameters.AddWithValue("@password", dec_pass)
        Dim dr As SqlDataReader = loginSQL.ExecuteReader()
        dr.Read()


        If dr.HasRows Then
            Session("userid") = dr("user_id")
        ElseIf dr.HasRows = False Then

            lblRegister.ForeColor = Drawing.Color.Red
            lblRegister.Text = "Incorrect Username/Password."
        End If
        dr.Close()
        conn.Close()

    End Sub





</script>



<head>
    <meta charset="utf-8" />
    <script src="http://html5shiv.googlecode.com/svn/trunk/html5.js"></script>
    <title></title>
    <meta name="keywords" content="" />
    <meta name="description" content="" />
    <link rel="stylesheet" href="style.css" type="text/css" media="screen, projection" />
</head>

<body>

    <form id="form1" runat="server">

<div id="wrapper">

    <header id="header">
        <strong>Header:</strong> Mobile CMS

        </header>


<section id="login">

    <div id="login-form">

         <p>

                    <asp:Label ID="lblUsername" runat="server" Font-Bold="True" Text="U:"></asp:Label>
&nbsp;<asp:TextBox ID="txtLoginUser" runat="server" BorderStyle="None" BorderWidth="0px" Wrap="False"></asp:TextBox>
&nbsp;
                    <asp:Label ID="lblUsername0" runat="server" Font-Bold="True" Text="P:"></asp:Label>
                    <asp:TextBox ID="txtLoginPass" runat="server" BorderStyle="None" BorderWidth="0px" TextMode="Password" Wrap="False"></asp:TextBox>
&nbsp;
                    <asp:Button ID="btnLogin" runat="server" BorderStyle="None" OnClick="Button1_Click" Text="Login" />

                </p>

                <p>

                    <asp:Label ID="lblRegister" runat="server" Font-Bold="True" Font-Underline="True" ForeColor="#0000CC" Text="Register"></asp:Label>

                    <asp:Label ID="lblLoggedIn" runat="server"></asp:Label>

                </p>
         <p>

                    &nbsp;</p>



    </div>

</section>

<div class="navigation-bar">
       <ul class="navigation-menu">

            <li><a href="#" class="home">Home</a></li>
            <li><a href="#" class="mainsettings">Settings</a></li>
            <li><a href="#" class="profile">Profile</a>

                <ul>
                    <li><a href="#" class="messages">Messages</a></li>
                    <li><a href="#" class="settings">Profile Settings</a></li>
                </ul>

            </li>
            <li><a href="#" class="uploads">Uploads</a></li>
            <li><a href="#" class="documents">Media</a>


                <ul>
                    <li><a href="#" class="docs">Documents</a></li>
                    <li><a href="#" class="others">Others</a></li>
                </ul>

            </li>

            <li><a href="#" class="projects">Projects</a>


                <ul>
                    <li><a href="#" class="yprojects">Your Projects</a></li>
                    <li><a href="#" class="otherprojects">Other Projects</a></li>
                </ul>

            </li>

        </ul>

    </div>


    <section id="middle">

        <div id="container">
            <div id="content">
                <div>
                    <asp:ContentPlaceHolder id="ContentPlaceHolder1" runat="server">

                    </asp:ContentPlaceHolder>
                </div>
        </div>
        </div>



    </section>

    <footer id="footer">
        <strong>Footer:</strong> adsfdsgfds
    </footer>

</div>

    </form>

</body>
</html>

截图:

怎么了？代码有什么问题？

我正在使用 VS 2012 Professional 和 SQL-Server 2012 Express

“查看配置文件”按钮的代码位于 btnProjSettings 下的 Admin.aspx 中:

  Protected Sub btnProjSettings_Click(sender As Object, e As EventArgs) Handles btnProjSettings.Click

        Dim conn2 As New SqlConnection("Data Source=BRIAN-PC\SQLEXPRESS;Initial Catalog=master_db;Integrated Security=True")
        Dim sqlComm2 As String = "SELECT project_id FROM projects WHERE project_name=@projectname"
        Dim sqlProjID As New SqlCommand

        conn2.Open()

        sqlProjID = New SqlCommand(sqlComm2, conn2)
        sqlProjID.Parameters.AddWithValue("@projectname", drpProjects.SelectedItem.Text)
        Dim datareader As SqlDataReader = sqlProjID.ExecuteReader()
        datareader.Read()


        If datareader.HasRows Then

            Dim UserID As String
            UserID = datareader("project_id").ToString

            Session("project_id") = UserID
            Server.Transfer("Project.aspx", True)

        End If

        datareader.Close()
        conn2.Close()



    End Sub

Answer 1

我相信您遇到的问题与在异步回发期间尝试重定向到另一个页面有关。

在您的 btnProjSettings_Click事件处理程序，替换:

Server.Transfer("Project.aspx", True)

和:

Dim jsRedirect As String = "window.location.pathname = 'Project.aspx';"
ScriptManager.RegisterClientScriptBlock(Page, Page.GetType(), "Redirect to Project.aspx", jsRedirect, true)

您收到该错误的原因是在异步回发期间，ASP.NET Ajax 库期望返回自定义消息，而不是标准 HTML 代码。反过来，当您调用 Server.Transfer ，服务器会返回指定页面的HTML代码；因此您看到的错误。