在不使用实时数据库的情况下，在按钮单击上选择 2 个下拉列表后，需要在下面的 GridView 中显示数据

Question

请帮助显示我们在 DropDownList 中选择的数据将立即填充 GridView 行。

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Menu2.aspx.cs" Inherits="MasalaStore.Menu2" %>

<html>
<head>
    <meta name="viewport" content="width=device-width, initial-scale=1" />
    <!-- General meta information -->
    <title>Menu</title>
    <%--    <meta name="keywords" content="" />
    <meta name="description" content="" />
    <meta name="robots" content="index, follow" />
    <meta charset="utf-8" />--%>
    <!-- // General meta information -->


    <!-- Load Javascript -->
    <script type="text/javascript" src="./js/jquery.js"></script>
    <script type="text/javascript" src="./js/jquery.query-2.1.7.js"></script>
    <script type="text/javascript" src="./js/rainbows.js"></script>
    <!-- // Load Javascipt -->

    <!-- Load stylesheets -->
    <link type="text/css" rel="stylesheet" href="css/style.css" media="screen" />
    <%--  <style>
    input[type='text']::placeholder
    {   
        text-align: center;      /* for Chrome, Firefox, Opera */
    }
    :-ms-input-placeholder
    { 
        text-align: center;      /* for IE 10-11 */
    }
    ::-webkit-input-placeholder
    { 
        text-align: center;      /* for IE Edge */
    }
</style>--%>
    <!-- // Load stylesheets -->
    <style>
        .mydropdownlist {
            color: #fff;
            font-size: 20px;
            padding: 5px 10px;
            border-radius: 5px;
            background-color: #cc2a41;
            font-weight: bold;
        }

        .mydropdownlist1 {
            color: #fff;
            font-size: 20px;
            padding: 5px 10px;
            border-radius: 5px 12px;
            background-color: #292929;
            font-weight: bold;
        }
    </style>
   
</head>

<body>

    <div id="wrapper">
        <form id="Form1" runat="server">
            <div>
                <div style="float:left;">
                    <asp:DropDownList ID="DropDownList1" runat="server" WatermarkText="Select a car" Width="300%" Height="30px" AutoPostBack="false" OnSelectedIndexChanged="ddl_onSelectIndexChanged">
                        <Items>
                            <asp:ListItem Text="Select" Value="0"></asp:ListItem>
                            <asp:ListItem Text="Haldi" Value="1"></asp:ListItem>
                            <asp:ListItem Text="Jeera" Value="2"></asp:ListItem>
                            <asp:ListItem Text="Amchoor" Value="3"></asp:ListItem>
                            <asp:ListItem Text="Ajwain" Value="4"></asp:ListItem>
                            <asp:ListItem Text="Dhaniya" Value="5"></asp:ListItem>
                            <asp:ListItem Text="Kasturi Methi" Value="6"></asp:ListItem>
                            <asp:ListItem Text="Mirch Pisi" Value="7"></asp:ListItem>
                            <asp:ListItem Text="Mirch Kuti" Value="8"></asp:ListItem>
                            <asp:ListItem Text="Kashmiri Mirch" Value="9"></asp:ListItem>
                            <asp:ListItem Text="Mirch Pili" Value="10"></asp:ListItem>
                            <asp:ListItem Text="Garam Masala" Value="11"></asp:ListItem>
                            <asp:ListItem Text="Chana Masala" Value="12"></asp:ListItem>
                            <asp:ListItem Text="Kitchen Kind" Value="13"></asp:ListItem>
                            <asp:ListItem Text="Dal Masala" Value="14"></asp:ListItem>
                            <asp:ListItem Text="Chat Masala" Value="15"></asp:ListItem>
                            <asp:ListItem Text="Sambhar Masala" Value="16"></asp:ListItem>
                            <asp:ListItem Text="Chhole Masala" Value="17"></asp:ListItem>
                            <asp:ListItem Text="Shahi Paneer Masala" Value="18"></asp:ListItem>
                            <asp:ListItem Text="Black Salt" Value="19"></asp:ListItem>
                            <asp:ListItem Text="Sendha Salt" Value="20"></asp:ListItem>
                            <asp:ListItem Text="Sonth Pisi" Value="21"></asp:ListItem>
                            <asp:ListItem Text="Tej Patta" Value="22"></asp:ListItem>
                            <asp:ListItem Text="Loung" Value="23"></asp:ListItem>
                            <asp:ListItem Text="Kali Mirch Sabut" Value="24"></asp:ListItem>
                            <asp:ListItem Text="Kali Mirch Pisi" Value="25"></asp:ListItem>
                            <asp:ListItem Text="Kalonji" Value="26"></asp:ListItem>
                            <asp:ListItem Text="Elaichi Badi" Value="27"></asp:ListItem>
                            <asp:ListItem Text="Elaichi Chhoti" Value="28"></asp:ListItem>
                            <asp:ListItem Text="Hing" Value="29"></asp:ListItem>
                            <asp:ListItem Text="Dalchini" Value="30"></asp:ListItem>
                            <asp:ListItem Text="Javitri" Value="31"></asp:ListItem>
                            <asp:ListItem Text="Jaifal" Value="32"></asp:ListItem>
                            <asp:ListItem Text="Postdana" Value="33"></asp:ListItem>
                            <asp:ListItem Text="Ajinomoto" Value="34"></asp:ListItem>
                            <asp:ListItem Text="Safed Mirch" Value="35"></asp:ListItem>
                            <asp:ListItem Text="Imli" Value="36"></asp:ListItem>
                            <asp:ListItem Text="Methi Dana" Value="37"></asp:ListItem>
                            <asp:ListItem Text="Raee" Value="38"></asp:ListItem>
                            <asp:ListItem Text="Saunf" Value="39"></asp:ListItem>
                            <asp:ListItem Text="Besan" Value="40"></asp:ListItem>
                            <asp:ListItem Text="Jeera Pisa" Value="41"></asp:ListItem>
                            <asp:ListItem Text="Pasta" Value="42"></asp:ListItem>
                            <asp:ListItem Text="Tarbuj ke Beej" Value="43"></asp:ListItem>
                            <asp:ListItem Text="Sabut Lal Mirch" Value="44"></asp:ListItem>
                            <asp:ListItem Text="Sabut Dhaniya" Value="45"></asp:ListItem>
                            <asp:ListItem Text="Moong Dal Mangodi" Value="46"></asp:ListItem>
                            <asp:ListItem Text="Sabudana" Value="47"></asp:ListItem>
                            <asp:ListItem Text="Supari" Value="48"></asp:ListItem>
                            <asp:ListItem Text="Star Flower" Value="49"></asp:ListItem>
                            <asp:ListItem Text="Til" Value="50"></asp:ListItem>
                            <asp:ListItem Text="Shahi Jeera" Value="51"></asp:ListItem>
                            <asp:ListItem Text="Anardana" Value="52"></asp:ListItem>
                        </Items>
                    </asp:DropDownList>
                </div>
                <div style="float:left; margin-left:350px;">
                    <asp:DropDownList ID="DropDownList2" runat="server" WatermarkText="Select a car" Width="300%" Height="30px" EnableViewState="true">
                        <Items>
                            <asp:ListItem Text="Select" Value="0"></asp:ListItem>
                            <asp:ListItem Text="10g" Value="1"></asp:ListItem>
                            <asp:ListItem Text="20g" Value="2"></asp:ListItem>
                            <asp:ListItem Text="50g" Value="3"></asp:ListItem>
                            <asp:ListItem Text="100g" Value="4"></asp:ListItem>
                            <asp:ListItem Text="200g" Value="5"></asp:ListItem>
                            <asp:ListItem Text="300g" Value="6"></asp:ListItem>
                            <asp:ListItem Text="400g" Value="7"></asp:ListItem>
                            <asp:ListItem Text="500g" Value="8"></asp:ListItem>
                            <asp:ListItem Text="600g" Value="9"></asp:ListItem>
                            <asp:ListItem Text="700g" Value="10"></asp:ListItem>
                            <asp:ListItem Text="800g" Value="11"></asp:ListItem>
                            <asp:ListItem Text="900g" Value="12"></asp:ListItem>
                            <asp:ListItem Text="1kg" Value="13"></asp:ListItem>
                            <asp:ListItem Text="2kg" Value="14"></asp:ListItem>
                            <asp:ListItem Text="3kg" Value="15"></asp:ListItem>
                            <asp:ListItem Text="4kg" Value="16"></asp:ListItem>
                            <asp:ListItem Text="5kg" Value="17"></asp:ListItem>
                            <asp:ListItem Text="10kg" Value="18"></asp:ListItem>
                        </Items>
                    </asp:DropDownList>
                </div>
                <div style="float:left; margin-left:300px;">
                    <asp:Button ID="Button" runat="server" Width="200%" Height="40px" Text="Submit" BackColor="BlanchedAlmond" OnClick="SubmitButton_Click">
                    </asp:Button>
                </div>
            </div>
            <div>
                 <asp:Panel ID="pnlGrid" CssClass="panel" runat="server" CellPadding="20" CellSpacing="25">
            <div style="text-align: center">

                <asp:GridView ID="GridView2" runat="server" AutoGenerateColumns="true" AllowPaging="false" AllowSorting="True" CssClass="gridview" BackColor="White" BorderColor="#999999" BorderStyle="None" BorderWidth="1px"
                    OnPageIndexChanging="OnPageIndexChanging" PageSize="10" CellPadding="4" ForeColor="#333333" OnRowDataBound="GridView1_RowDataBound" GridLines="Vertical">
                    <Columns>
                        <%--<asp:BoundField ItemStyle-Width="150px" ItemStyle-Height="40px" HeaderText="Masala Name" />
                        <asp:BoundField ItemStyle-Width="100px" HeaderText="Quantity" />
                        <asp:BoundField ItemStyle-Width="100px" HeaderText="Prize" />--%>
                        <asp:TemplateField HeaderText="S.NO."><ItemTemplate><%# Container.DataItemIndex + 1 %></ItemTemplate></asp:TemplateField>
                    </Columns>
                    <HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" />
                    <RowStyle BackColor="#F7F6F3" ForeColor="#333333" />
                    <HeaderStyle CssClass="gridViewHeader" />
                    <RowStyle CssClass="gridViewRow" />
                    <AlternatingRowStyle CssClass="gridViewAltRow" />
                    <SelectedRowStyle CssClass="gridViewSelectedRow" />
                    <PagerStyle CssClass="gridViewPager" />
                </asp:GridView>

            </div>
        </asp:Panel>
            </div>
            <asp:Label ID="lblRowNumber" runat="server"></asp:Label>
        </form>
    </div>
</body>
</html>

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代码隐藏：在此我尝试了一个简单的代码来绑定下拉数据，所以第一行是在提交下拉列表选择之后出现的，但是在那之后如果我想从下拉列表中进行另一个选择并提交那么它就不会占用另一行.

using System;
using System.Data.SqlClient;
using System.Configuration;
using System.Data;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace MasalaStore
{
    public partial class Menu2 : System.Web.UI.Page
    {
        SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["mycon"].ToString());
        protected void Page_Load(object sender, EventArgs e)
        {

        }

        protected void SubmitButton_Click(object sender, EventArgs e)
        {
            BindGrid();
        }
        private void BindGrid()
        {
            //if (DropDownList1.Text != null && DropDownList2.Text != null)
            //{

            DataTable dt = new DataTable();
            //dt.Columns.Add("S.No.", typeof(Int32));
            dt.Columns.Add("ITEM", typeof(string));
            dt.Columns.Add("QUANTITY", typeof(string));
            dt.Columns.Add("PRIZE", typeof(string));

            DataRow dtrow = dt.NewRow();    // Create New Row and Bind Data to Columns
            dtrow["Item"] = DropDownList1.SelectedItem;
            dtrow["Quantity"] = DropDownList2.SelectedItem;
            dtrow["Prize"] = "#";
            dt.Rows.Add(dtrow);

            //if (dt.Rows.Count > 0)
            //{
                GridView2.DataSource = dt;
                GridView2.DataBind();
                DropDownList1.ClearSelection();
                DropDownList2.ClearSelection();
            //}
        }

        protected void OnPageIndexChanging(object sender, GridViewPageEventArgs e)
        {
            GridView2.PageIndex = e.NewPageIndex;
            this.BindGrid();
        }

        protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
        {
            if (e.Row.RowType == DataControlRowType.DataRow)
            {
                if ((e.Row.Cells[1].Text).ToUpper() == "OUT OF STOCK")
                {
                    // CHANGE THE COLOR OF THE CELL.
                    e.Row.Cells[1].BackColor = System.Drawing.Color.Crimson;
                    e.Row.Cells[1].ForeColor = System.Drawing.Color.WhiteSmoke;
                }
            }
        }

        protected void ddl_onSelectIndexChanged(object sender, System.EventArgs e)
        {

        }

    }
}

Answer 1

好的，那我们就可以使用这段代码了：

点击提交将添加行，清除两个下拉菜单。

代码将如下所示：

请注意我们如何在表单 class 级别声明 MyTable。

private DataTable MyTable = new DataTable();

public void Page_Load(object sender, System.EventArgs e)
{
    if (IsPostBack == false)
    {
        SetUpGrid();
        ViewState["MyTable"] = MyTable;
    }
    else
        MyTable = ViewState["MyTable"];
}


public void SetUpGrid()
{
    MyTable.Columns.Add("ITEM", typeof(string));
    MyTable.Columns.Add("QUANTITY", typeof(Int32));
    MyTable.Columns.Add("PRIZE", typeof(Int32));
}

protected void Button_Click(object sender, EventArgs e)
{

    // add row to table

    DataRow OneRow = MyTable.Rows.Add;

    OneRow("ITEM") = DropDownList1.SelectedItem.Text;
    OneRow("QUANTITY") = 1;
    OneRow("PRIZE") = DropDownList2.SelectedItem.Value;

    GridView2.DataSource = MyTable;
    GridView2.DataBind();

    DropDownList1.ClearSelection();
    DropDownList2.ClearSelection();
}
}

所以这里的技巧是在第一页加载时：

设置 table。

但是，我们必须保存此 table 的状态。这使得添加一行变得很容易。每次我们添加新行时，我们都会重新绑定网格，清除下拉列表。

在不使用实时数据库的情况下，在按钮单击上选择 2 个下拉列表后，需要在下面的 GridView 中显示数据

Need to display data in GridView below after Selection of 2 DropDowns on their Button Click without using database in real time

c#

asp.net

binding

gridview

dropdownlistfor