当前位置： 文江博客话题详情

ASP.NET 错误：必须声明标量变量

发布于 2025-01-04 16:13:11 字数 7842 浏览 3 评论 0原文

我知道我显然缺少/不正确地声明了一个变量，但我不太确定如何解决这个问题。每当我单击“btnUpdate”更新数据库中的信息（基于文本字段中的内容）时，我都会收到此错误。我已发布以下代码以供审核，感谢您的帮助！

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs"     Inherits="WebApplication1.WebForm1" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div>

<div class="floater">
<h3>Books</h3>
<asp:DropDownList
    id="DropDownList_Books"
    DataSourceId="srcBooks"
    DataTextField="Title"
    DataValueField="Id"
    Runat="server" />
    <asp:Button ID="btnSelect" runat="server" Text="View Detials" Width="106px" 
        onclick="btnSelect_Click" />
</div>

<asp:GridView
    id="grdBooks"
    DataSourceID="srcBooks_Description"
    Runat="server" Visible="False" />

    <asp:Button ID="btnEdit" runat="server" onclick="btnEdit_Click" Text="Edit" />

</div>

<asp:Button ID="btnCancel" runat="server" onclick="btnCancel_Click" 
    style="z-index: 1; left: 464px; top: 153px; position: absolute; height: 26px" 
    Text="Cancel" Visible="False" />

<asp:FormView
    id="frmEditBook"
    DataKeyNames="Cat_Id"
    DataSourceId="srcBooks_Description"
    DefaultMode="Edit"
    Runat="server" Visible="False" 
    style="z-index: 1; left: 391px; top: 87px; position: absolute; height: 111px; width: 206px">
    <EditItemTemplate>
    <asp:Label
        id="lblTitle"
        Text="Title:"
        AssociatedControlID="txtTitle"
        Runat="server" />
    <asp:TextBox
        id="txtTitle"
        Text='<%#Bind("Title")%>'
        Runat="server" />
    <br />
    <asp:Label
        id="lblDescription"
        Text="Description:"
        AssociatedControlID="txtDescription"
        Runat="server" />
    <asp:TextBox
        id="txtDescription"
        Text='<%#Bind("Description")%>'
        Runat="server" />
    <br />
    <asp:Button
        id="btnUpdate"
        Text="Update"
        CommandName="Update"
        Runat="server" />
    </EditItemTemplate>
</asp:FormView>
<asp:SqlDataSource ID="srcBooks" runat="server" 
    ConnectionString="Data Source=&quot;ebiz.isy.vcu.edu, 14330&quot;;Initial Catalog=spring12u08;Persist Security Info=True;User ID=Spring12u08;Password=INFO451u08" 
    onselecting="srcBooks_Selecting" ProviderName="System.Data.SqlClient" SelectCommand="SELECT Title,Id FROM PARTIN_ID">

</asp:SqlDataSource>

<asp:SqlDataSource ID="srcBooks_Description" runat="server" 
    ConnectionString="Data Source=&quot;ebiz.isy.vcu.edu, 14330&quot;;Initial Catalog=spring12u08;Persist Security Info=True;User ID=Spring12u08;Password=INFO451u08" 
    onselecting="srcBooks_Selecting" ProviderName="System.Data.SqlClient" SelectCommand="SELECT * FROM PARTIN_INFO WHERE Cat_ID=@Id" UpdateCommand="UPDATE PARTIN_INFO SET Title=@Title,
        Description=@Description WHERE Cat_Id=@Id">
<SelectParameters>
        <asp:ControlParameter
            Name="Id"
            Type="int32"                
            ControlID="DropDownList_Books" />
    </SelectParameters>

</asp:SqlDataSource>

</form>
</body>
</html>

更新了代码，出现新错误：在 ControlParameter“Title”中找不到控件“txtTitle”。

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

<div class="floater">
<h3>Books</h3>
<asp:DropDownList
    id="DropDownList_Books"
    DataSourceId="srcBooks"
    DataTextField="Title"
    DataValueField="Id"
    Runat="server" />
    <asp:Button ID="btnSelect" runat="server" Text="View Detials" Width="106px" 
        onclick="btnSelect_Click" />
</div>

<asp:GridView
    id="grdBooks"
    DataSourceID="srcBooks_Description"
    Runat="server" Visible="False" />

    <asp:Button ID="btnEdit" runat="server" onclick="btnEdit_Click" Text="Edit" />

</div>

<asp:Button ID="btnCancel" runat="server" onclick="btnCancel_Click" 
    style="z-index: 1; left: 464px; top: 153px; position: absolute; height: 26px" 
    Text="Cancel" Visible="False" />

<asp:FormView
    id="frmEditBook"
    DataKeyNames="Cat_Id"
    DataSourceId="srcBooks_Description"
    DefaultMode="Edit"
    Runat="server" Visible="False" 

    style="z-index: 1; left: 391px; top: 87px; position: absolute; height: 111px; width: 206px" >
    <EditItemTemplate>
    <asp:Label
        id="lblTitle"
        Text="Title:"
        AssociatedControlID="txtTitle"
        Runat="server" />
    <asp:TextBox
        id="txtTitle"
        Text='<%#Bind("Title")%>'
        Runat="server" />
    <br />
    <asp:Label
        id="lblDescription"
        Text="Description:"
        AssociatedControlID="txtDescription"
        Runat="server" />
    <asp:TextBox
        id="txtDescription"
        Text='<%#Bind("Description")%>'
        Runat="server" />
    <br />
    <asp:Button
        id="btnUpdate"
        Text="Update"
        CommandName="Update"
        Runat="server" />
    </EditItemTemplate>
</asp:FormView>
<asp:SqlDataSource ID="srcBooks" runat="server" 
    ConnectionString="Data Source=&quot;ebiz.isy.vcu.edu, 14330&quot;;Initial Catalog=spring12u08;Persist Security Info=True;User ID=Spring12u08;Password=INFO451u08" 
    onselecting="srcBooks_Selecting" ProviderName="System.Data.SqlClient" SelectCommand="SELECT Title,Id FROM PARTIN_ID">

</asp:SqlDataSource>

<asp:SqlDataSource ID="srcBooks_Description" runat="server" 
    ConnectionString="Data Source=&quot;ebiz.isy.vcu.edu, 14330&quot;;Initial Catalog=spring12u08;Persist Security Info=True;User ID=Spring12u08;Password=INFO451u08" 
    onselecting="srcBooks_Selecting" ProviderName="System.Data.SqlClient" SelectCommand="SELECT * FROM PARTIN_INFO WHERE Cat_ID=@Id" UpdateCommand="UPDATE PARTIN_INFO SET Title=@Title,
        Description=@Description WHERE Cat_Id=@Id">
<SelectParameters>
        <asp:ControlParameter
            Name="Id"
            Type="int32"                
            ControlID="DropDownList_Books"
            PropertyName="SelectedValue" />
    </SelectParameters>
     <UpdateParameters>
          <asp:ControlParameter Name="Title" ControlId="txtTitle" PropertyName="Text"/>
          <asp:ControlParameter Name="Description" ControlId="txtDescription" PropertyName="Text"/>
          <asp:ControlParameter Name="Id" ControlId="DropDownList_Books" PropertyName="SelectedValue"/>
      </UpdateParameters>

</asp:SqlDataSource>

</form>

还有后面的代码：

namespace WebApplication1
{
public partial class WebForm1 : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }

    protected void srcBooks_Selecting(object sender, SqlDataSourceSelectingEventArgs e)
    {

    }

    protected void btnSelect_Click(object sender, EventArgs e)
    {
        grdBooks.Visible = true;
    }

    protected void btnCancel_Click(object sender, EventArgs e)
    {
        frmEditBook.Visible = false;
    }

    protected void btnEdit_Click(object sender, EventArgs e)
    {
        frmEditBook.Visible = true;
        btnCancel.Visible = true;
    }

    protected void btnUpdate_Click(object sender, EventArgs e)
    {
        try
        {
            srcBooks_Description.Update();
        }
        catch (Exception except)
        {
            // Handle the Exception.
        }
    }






    }
}
原文

I know I'm obviously missing / have improperly declared a variable but I'm not quite sure how to fix that. I am getting this error when ever I click "btnUpdate" to update the information in the database (based on whats in the text fields). I've posted the code below for review, thanks for the help!

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs"     Inherits="WebApplication1.WebForm1" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<div>

<div class="floater">
<h3>Books</h3>
<asp:DropDownList
    id="DropDownList_Books"
    DataSourceId="srcBooks"
    DataTextField="Title"
    DataValueField="Id"
    Runat="server" />
    <asp:Button ID="btnSelect" runat="server" Text="View Detials" Width="106px" 
        onclick="btnSelect_Click" />
</div>

<asp:GridView
    id="grdBooks"
    DataSourceID="srcBooks_Description"
    Runat="server" Visible="False" />

    <asp:Button ID="btnEdit" runat="server" onclick="btnEdit_Click" Text="Edit" />

</div>

<asp:Button ID="btnCancel" runat="server" onclick="btnCancel_Click" 
    style="z-index: 1; left: 464px; top: 153px; position: absolute; height: 26px" 
    Text="Cancel" Visible="False" />

<asp:FormView
    id="frmEditBook"
    DataKeyNames="Cat_Id"
    DataSourceId="srcBooks_Description"
    DefaultMode="Edit"
    Runat="server" Visible="False" 
    style="z-index: 1; left: 391px; top: 87px; position: absolute; height: 111px; width: 206px">
    <EditItemTemplate>
    <asp:Label
        id="lblTitle"
        Text="Title:"
        AssociatedControlID="txtTitle"
        Runat="server" />
    <asp:TextBox
        id="txtTitle"
        Text='<%#Bind("Title")%>'
        Runat="server" />
    <br />
    <asp:Label
        id="lblDescription"
        Text="Description:"
        AssociatedControlID="txtDescription"
        Runat="server" />
    <asp:TextBox
        id="txtDescription"
        Text='<%#Bind("Description")%>'
        Runat="server" />
    <br />
    <asp:Button
        id="btnUpdate"
        Text="Update"
        CommandName="Update"
        Runat="server" />
    </EditItemTemplate>
</asp:FormView>
<asp:SqlDataSource ID="srcBooks" runat="server" 
    ConnectionString="Data Source="ebiz.isy.vcu.edu, 14330";Initial Catalog=spring12u08;Persist Security Info=True;User ID=Spring12u08;Password=INFO451u08" 
    onselecting="srcBooks_Selecting" ProviderName="System.Data.SqlClient" SelectCommand="SELECT Title,Id FROM PARTIN_ID">

</asp:SqlDataSource>

<asp:SqlDataSource ID="srcBooks_Description" runat="server" 
    ConnectionString="Data Source="ebiz.isy.vcu.edu, 14330";Initial Catalog=spring12u08;Persist Security Info=True;User ID=Spring12u08;Password=INFO451u08" 
    onselecting="srcBooks_Selecting" ProviderName="System.Data.SqlClient" SelectCommand="SELECT * FROM PARTIN_INFO WHERE Cat_ID=@Id" UpdateCommand="UPDATE PARTIN_INFO SET Title=@Title,
        Description=@Description WHERE Cat_Id=@Id">
<SelectParameters>
        <asp:ControlParameter
            Name="Id"
            Type="int32"                
            ControlID="DropDownList_Books" />
    </SelectParameters>

</asp:SqlDataSource>

</form>
</body>
</html>

Updated Code with new error: Could not find control 'txtTitle' in ControlParameter 'Title'.

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

<div class="floater">
<h3>Books</h3>
<asp:DropDownList
    id="DropDownList_Books"
    DataSourceId="srcBooks"
    DataTextField="Title"
    DataValueField="Id"
    Runat="server" />
    <asp:Button ID="btnSelect" runat="server" Text="View Detials" Width="106px" 
        onclick="btnSelect_Click" />
</div>

<asp:GridView
    id="grdBooks"
    DataSourceID="srcBooks_Description"
    Runat="server" Visible="False" />

    <asp:Button ID="btnEdit" runat="server" onclick="btnEdit_Click" Text="Edit" />

</div>

<asp:Button ID="btnCancel" runat="server" onclick="btnCancel_Click" 
    style="z-index: 1; left: 464px; top: 153px; position: absolute; height: 26px" 
    Text="Cancel" Visible="False" />

<asp:FormView
    id="frmEditBook"
    DataKeyNames="Cat_Id"
    DataSourceId="srcBooks_Description"
    DefaultMode="Edit"
    Runat="server" Visible="False" 

    style="z-index: 1; left: 391px; top: 87px; position: absolute; height: 111px; width: 206px" >
    <EditItemTemplate>
    <asp:Label
        id="lblTitle"
        Text="Title:"
        AssociatedControlID="txtTitle"
        Runat="server" />
    <asp:TextBox
        id="txtTitle"
        Text='<%#Bind("Title")%>'
        Runat="server" />
    <br />
    <asp:Label
        id="lblDescription"
        Text="Description:"
        AssociatedControlID="txtDescription"
        Runat="server" />
    <asp:TextBox
        id="txtDescription"
        Text='<%#Bind("Description")%>'
        Runat="server" />
    <br />
    <asp:Button
        id="btnUpdate"
        Text="Update"
        CommandName="Update"
        Runat="server" />
    </EditItemTemplate>
</asp:FormView>
<asp:SqlDataSource ID="srcBooks" runat="server" 
    ConnectionString="Data Source="ebiz.isy.vcu.edu, 14330";Initial Catalog=spring12u08;Persist Security Info=True;User ID=Spring12u08;Password=INFO451u08" 
    onselecting="srcBooks_Selecting" ProviderName="System.Data.SqlClient" SelectCommand="SELECT Title,Id FROM PARTIN_ID">

</asp:SqlDataSource>

<asp:SqlDataSource ID="srcBooks_Description" runat="server" 
    ConnectionString="Data Source="ebiz.isy.vcu.edu, 14330";Initial Catalog=spring12u08;Persist Security Info=True;User ID=Spring12u08;Password=INFO451u08" 
    onselecting="srcBooks_Selecting" ProviderName="System.Data.SqlClient" SelectCommand="SELECT * FROM PARTIN_INFO WHERE Cat_ID=@Id" UpdateCommand="UPDATE PARTIN_INFO SET Title=@Title,
        Description=@Description WHERE Cat_Id=@Id">
<SelectParameters>
        <asp:ControlParameter
            Name="Id"
            Type="int32"                
            ControlID="DropDownList_Books"
            PropertyName="SelectedValue" />
    </SelectParameters>
     <UpdateParameters>
          <asp:ControlParameter Name="Title" ControlId="txtTitle" PropertyName="Text"/>
          <asp:ControlParameter Name="Description" ControlId="txtDescription" PropertyName="Text"/>
          <asp:ControlParameter Name="Id" ControlId="DropDownList_Books" PropertyName="SelectedValue"/>
      </UpdateParameters>

</asp:SqlDataSource>

</form>

Also code behind:

namespace WebApplication1
{
public partial class WebForm1 : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }

    protected void srcBooks_Selecting(object sender, SqlDataSourceSelectingEventArgs e)
    {

    }

    protected void btnSelect_Click(object sender, EventArgs e)
    {
        grdBooks.Visible = true;
    }

    protected void btnCancel_Click(object sender, EventArgs e)
    {
        frmEditBook.Visible = false;
    }

    protected void btnEdit_Click(object sender, EventArgs e)
    {
        frmEditBook.Visible = true;
        btnCancel.Visible = true;
    }

    protected void btnUpdate_Click(object sender, EventArgs e)
    {
        try
        {
            srcBooks_Description.Update();
        }
        catch (Exception except)
        {
            // Handle the Exception.
        }
    }






    }
}

如果你对这篇内容有疑问，欢迎到本站社区发帖提问 参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。

扫码二维码加入Web技术交流群

发布评论

需要 登录 才能够评论， 你可以免费 注册 一个本站的账号。

评论（1）

纸伞微斜 2025-01-11 16:13:12

我遇到了这个问题。我把原表中的所有字段名都改成了一个单词或者下划线分隔的多个单词，比如card_number，修改了select和update语句，效果很好。

I had this problem. I changed all the field names in the original table to one word or multiple words separated by an underline, such as card_number, changed the select and update statements and it worked fine.

回复 原文
~没有更多了~

关于作者

握住我的手

暂无简介

文章
评论
27 人气
发私信

相关话题

更多

热门标签

操作系统 程序设计 IT运维 Linux系统管理 JavaScript 服务器应用 solaris C/C++ PHP Shell BSD Vue.js aix Oracle Python HTML 系统管理 HTML5 CSS 前端
更多

推荐作者

qq_aHcEbj

文章 0 评论 0

qq_ikhFfg

文章 0 评论 0

寻找我们的幸福

文章 0 评论 0

把昨日还给我

文章 0 评论 0

wj_zym

文章 0 评论 0

巴黎夜雨

文章 0 评论 0

更多

友情链接

文江博客
    我们使用 Cookies 和其他技术来定制您的体验包括您的登录状态等。通过阅读我们的 隐私政策 了解更多相关信息。 单击 接受 或继续使用网站，即表示您同意使用 Cookies 和您的相关数据。
    原文