以编程方式声明变量时出现“必须声明标量变量”错误答案

【问题标题】："Must Declare the Scalar Variable" error when programatically declaring variables以编程方式声明变量时出现“必须声明标量变量”错误
【发布时间】：2012-12-26 18:43:22
【问题描述】：

这是一个令人头疼的问题（至少对我而言）。

我有一个 GridView，用户可以在其中为很多数据字段在页脚中输入信息。一般来说，它们遵循以下格式：

<asp:TemplateField HeaderText="Date" ItemStyle-HorizontalAlign="Center">
<FooterTemplate>
    <asp:TextBox ID="NewDate" runat="server" Width="25px" Height="10px" Font-Size="Smaller" ValidateRequestMode="Disabled"></asp:TextBox>
    <asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ControlToValidate="NewDate" Display="Dynamic" ErrorMessage="You must enter a  valid date (MM/DD/YYYY) before submitting...">*</asp:RequiredFieldValidator>
</FooterTemplate>
<ItemTemplate>
    <asp:Label ID="Label1" runat="server" Text='<%# Bind("WeekOf","{0:MM/dd}") %>'></asp:Label>
</ItemTemplate>

InsertCommand 看起来像这样（概括）：

InsertCommand="INSERT INTO [Table] (WeekOf,User,OtherData)
      VALUES (Convert(Date,@WeekOf,101), @User, @OtherData)">

@User 由运行良好的 InsertParameter 控制（我知道这一点，因为它与我的功能 SelectCommand / SelectParameter 完全相同）。

无论如何，由于这些字段位于 gridview 中，我无法为它们分配静态 InsertParameters，因为它们位于 GridView 的页脚中，随着行数的变化而变化（我知道......关于如何这样做会很棒），所以我试图以编程方式声明变量，如this，但是我得到一个“必须声明标量变量“@WeekOf”错误。这是我的 GridView_RowCommand 函数的总体思路：

 TextBox WeekOfin = SalesReportingGridView.FooterRow.FindControl("NewDate") as TextBox;
 TextBox OtherDatain = SalesReportingGridView.FooterRow.FindControl("NewOtherData") as TextBox;

 SqlParameter WeekOf = new SqlParameter("@WeekOf", SqlDbType.VarChar, 30);
 WeekOf.Direction = ParameterDirection.Input;
 WeekOf.Value = WeekOfin.Text;
 insertParameters.Add(WeekOf);

 SqlParameter OtherData = new SqlParameter("@OtherData", SqlDbType.Int);
 OtherData.Direction = ParameterDirection.Input;
 OtherData.Value = OtherDatain.Text;
 insertParameters.Add(OtherData);

 SqlDataSource2.Insert();

这是完整的相关代码--

        private List<SqlParameter> insertParameters = new List<SqlParameter>();

    protected void SqlDataSource2_Inserting(object sender, SqlDataSourceCommandEventArgs e)
    {
        e.Command.Parameters.Clear();
        foreach (SqlParameter p in insertParameters)
            e.Command.Parameters.Add(p);

    }

    protected void SalesReportingGridView_RowCommand(object sender, GridViewCommandEventArgs e)
    {
        if (e.CommandName == "Insert" && Page.IsValid)
        {
            TextBox WeekOfin = SalesReportingGridView.FooterRow.FindControl("NewDate") as TextBox;
            TextBox Data1in = SalesReportingGridView.FooterRow.FindControl("NewData1") as TextBox;
            TextBox Data2in = SalesReportingGridView.FooterRow.FindControl("NewData2") as TextBox;
            TextBox Data3in = SalesReportingGridView.FooterRow.FindControl("NewData3") as TextBox;
            TextBox Data4in = SalesReportingGridView.FooterRow.FindControl("NewData4") as TextBox;
            TextBox Data5in = SalesReportingGridView.FooterRow.FindControl("NewData5") as TextBox;
            TextBox Data6in = SalesReportingGridView.FooterRow.FindControl("NewData6") as TextBox;
            TextBox Data7in = SalesReportingGridView.FooterRow.FindControl("NewData7") as TextBox;
            TextBox Data8in = SalesReportingGridView.FooterRow.FindControl("NewData8") as TextBox;
            TextBox Data9in = SalesReportingGridView.FooterRow.FindControl("NewData9") as TextBox;
            TextBox Data10in = SalesReportingGridView.FooterRow.FindControl("NewData10") as TextBox;
            TextBox Data11in = SalesReportingGridView.FooterRow.FindControl("NewData11") as TextBox;
            TextBox Data12in = SalesReportingGridView.FooterRow.FindControl("NewData12") as TextBox;
            TextBox Data13in = SalesReportingGridView.FooterRow.FindControl("NewData13") as TextBox;
            TextBox Data14in = SalesReportingGridView.FooterRow.FindControl("NewData14") as TextBox;
            TextBox Data15in = SalesReportingGridView.FooterRow.FindControl("NewData15") as TextBox;
            TextBox Data16in = SalesReportingGridView.FooterRow.FindControl("NewData16") as TextBox;
            TextBox Data17in = SalesReportingGridView.FooterRow.FindControl("NewData17") as TextBox;
            TextBox Data18in = SalesReportingGridView.FooterRow.FindControl("NewData18") as TextBox;
            TextBox Data19in = SalesReportingGridView.FooterRow.FindControl("NewData19") as TextBox;
            TextBox Data20in = SalesReportingGridView.FooterRow.FindControl("NewData20") as TextBox;
            TextBox Data21in = SalesReportingGridView.FooterRow.FindControl("NewData21") as TextBox;

            SqlParameter WeekOf = new SqlParameter("@WeekOf", SqlDbType.VarChar, 30);
            WeekOf.Direction = ParameterDirection.Input;
            WeekOf.Value = WeekOfin.Text;
            insertParameters.Add(WeekOf);

            SqlParameter Data1 = new SqlParameter("@Data1", SqlDbType.Int);
            Data1.Direction = ParameterDirection.Input;
            Data1.Value = Data1in.Text;
            insertParameters.Add(Data1);

            SqlParameter Data2 = new SqlParameter("@Data2", SqlDbType.Int);
            Data2.Direction = ParameterDirection.Input;
            Data2.Value = Data2in.Text;
            insertParameters.Add(Data2);

            SqlParameter Data3 = new SqlParameter("@Data3", SqlDbType.Int);
            Data3.Direction = ParameterDirection.Input;
            Data3.Value = Data3in.Text;
            insertParameters.Add(Data3);

            SqlParameter Data4 = new SqlParameter("@Data4", SqlDbType.Int);
            Data4.Direction = ParameterDirection.Input;
            Data4.Value = Data4in.Text;
            insertParameters.Add(Data4);

            SqlParameter Data5 = new SqlParameter("@Data5", SqlDbType.Int);
            Data5.Direction = ParameterDirection.Input;
            Data5.Value = Data5in.Text;
            insertParameters.Add(Data5);

            SqlParameter Data6 = new SqlParameter("@Data6", SqlDbType.Int);
            Data6.Direction = ParameterDirection.Input;
            Data6.Value = Data6in.Text;
            insertParameters.Add(Data6);

            SqlParameter Data7 = new SqlParameter("@Data7", SqlDbType.Int);
            Data7.Direction = ParameterDirection.Input;
            Data7.Value = Data7in.Text;
            insertParameters.Add(Data7);

            SqlParameter Data8 = new SqlParameter("@Data8", SqlDbType.Int);
            Data8.Direction = ParameterDirection.Input;
            Data8.Value = Data8in.Text;
            insertParameters.Add(Data8);

            SqlParameter Data9 = new SqlParameter("@Data9", SqlDbType.Int);
            Data9.Direction = ParameterDirection.Input;
            Data9.Value = Data9in.Text;
            insertParameters.Add(Data9);

            SqlParameter Data10 = new SqlParameter("@Data10", SqlDbType.Int);
            Data10.Direction = ParameterDirection.Input;
            Data10.Value = Data10in.Text;
            insertParameters.Add(Data10);

            SqlParameter Data11 = new SqlParameter("@Data11", SqlDbType.Int);
            Data11.Direction = ParameterDirection.Input;
            Data11.Value = Data11in.Text;
            insertParameters.Add(Data11);

            SqlParameter Data12 = new SqlParameter("@Data12", SqlDbType.Int);
            Data12.Direction = ParameterDirection.Input;
            Data12.Value = Data12in.Text;
            insertParameters.Add(Data12);

            SqlParameter Data13 = new SqlParameter("@Data13", SqlDbType.Int);
            Data13.Direction = ParameterDirection.Input;
            Data13.Value = Data13in.Text;
            insertParameters.Add(Data13);

            SqlParameter Data14 = new SqlParameter("@Data14", SqlDbType.Int);
            Data14.Direction = ParameterDirection.Input;
            Data14.Value = Data14in.Text;
            insertParameters.Add(Data14);

            SqlParameter Data15 = new SqlParameter("@Data15", SqlDbType.Int);
            Data15.Direction = ParameterDirection.Input;
            Data15.Value = Data15in.Text;
            insertParameters.Add(Data15);

            SqlParameter Data16 = new SqlParameter("@Data16", SqlDbType.Int);
            Data16.Direction = ParameterDirection.Input;
            Data16.Value = Data16in.Text;
            insertParameters.Add(Data16);

            SqlParameter Data17 = new SqlParameter("@Data17", SqlDbType.Int);
            Data17.Direction = ParameterDirection.Input;
            Data17.Value = Data17in.Text;
            insertParameters.Add(Data17);

            SqlParameter Data18 = new SqlParameter("@Data18", SqlDbType.Int);
            Data18.Direction = ParameterDirection.Input;
            Data18.Value = Data18in.Text;
            insertParameters.Add(Data18);

            SqlParameter Data19 = new SqlParameter("@Data19", SqlDbType.Int);
            Data19.Direction = ParameterDirection.Input;
            Data19.Value = Data19in.Text;
            insertParameters.Add(Data19);

            SqlParameter Data20 = new SqlParameter("@Data20", SqlDbType.Int);
            Data20.Direction = ParameterDirection.Input;
            Data20.Value = Data20in.Text;
            insertParameters.Add(Data20);

            SqlParameter Data21 = new SqlParameter("@Data21", SqlDbType.Int);
            Data21.Direction = ParameterDirection.Input;
            Data21.Value = Data21in.Text;
            insertParameters.Add(Data21);

            SqlDataSource2.Insert();
        }
    }
}

}

【问题讨论】：

当你单步执行代码时..它在哪里出错..你捕获了什么异常..你在哪里执行查询..？
与论坛网站不同，我们不使用“谢谢”、“感谢任何帮助”或Stack Overflow 上的签名。请参阅“Should 'Hi', 'thanks,' taglines, and salutations be removed from posts?.
@DJKRAZE 当我打开网站时，它会正常加载页面，但是当我尝试提交时，它卡在 SqlDataSource2.Insert(); ，具有以下异常详细信息：“System.Data.SqlClient.SqlException：必须声明标量变量“@WeekOf”。”
您能否粘贴代码，即清理它并显示与代码相关的一两个相关方法。它会更容易阅读。该错误意味着您没有为WeekOf 正确我建议使用 Parameter.AddWithValues("@WeekOf", WeekOf);
你将参数添加到insertParameters，但是与SQL命令关联的参数集合在哪里？

标签： c# sql-server visual-studio gridview visual-studio-2012

【解决方案1】：

看看这个如何添加参数的例子，并按照这个作为模板我将粘贴一些代码让你开始，你必须填写其余的..

根据您计算 WeekOf 的方式，我会在 using 语句之外放置或获取该值，并将其传递到您尝试执行 Convert(Date,@WeekOf, 101) 的位置

using (SqlConnection connection = new SqlConnection(connectionString))
{
    SqlCommand cmd = new SqlCommand("InsertCommand="INSERT INTO [Table] WeekOf,User,OtherData)
  VALUES (Convert(Date,@WeekOf,101), @User, @OtherData)"");
    cmd.CommandType = CommandType.Text;
    cmd.Connection = connection;
    cmd.Parameters.AddWithValue("@WeekOf", WeekOfin.Text);
    cmd.Parameters.AddWithValue("@User", YourUser.Text);
    cmd.Parameters.AddWithValue("@OtherData", txtAddress.Text);
    ...
    ...
    connection.Open();
    try
    {
      cmd.ExecuteNonQuery();
    }
    catch (SqlException ex)
    {
      //MessageDlg.Show(ex.Message); //do what ever kind of logging or error trapping here that you want.. 
    }
    //You will need to explain how you are populating or getting
    // the MM/YY for WeekOf 
    //Personally I would refactor this code it's a bit unorthodox 
}

【讨论】：