两个dropDownList和一个GridView的选择与显示

很久没有写ASP.NET了，今天有看到论坛上一个问题：
"两个dropDownList和一个GridView，已经进行了数据绑定，现在想让第一个下拉菜单的数据改变时，第二个下拉菜单自动变到相应的数据，同时选中gridview中相对应的行，不知道如何实现，很急，求大神相助"

其实，实现起来算得上简单，下面先从准备数据开始，创建一个对象Customer:

source code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

/// <summary>
/// Summary description for Customer
/// </summary>
namespace Insus.NET
{
    public class Customer
    {
        private int _CustomerID;
        private string _CustomerName;
        private string _PID;
        private bool _IsActived;

        public int CustomerID
        {
            get { return _CustomerID; }
            set { _CustomerID = value; }
        }
        public string CustomerName
        {
            get { return _CustomerName; }
            set { _CustomerName = value; }
        }
        public string PID
        {
            get { return _PID; }
            set { _PID = value; }
        }
        public bool IsActived
        {
            get { return _IsActived; }
            set { _IsActived = value; }
        }
    }
}

View Code

接下来，我们创建一个实具，数据来源全在此类实现 CustomerEntity:

source code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

/// <summary>
/// Summary description for CustomerEntity
/// </summary>
namespace Insus.NET
{
    public class CustomerEntity
    {
        public CustomerEntity()
        {
            //
            // TODO: Add constructor logic here
            //
        }

        public IEnumerable<Customer> Customers = new List<Customer> {
            new Customer {CustomerID = 9,CustomerName = "张三",PID = "123456789012"  },
            new Customer {CustomerID = 10,CustomerName = "李四",PID = "321245677812"  },
            new Customer {CustomerID = 30,CustomerName = "吴广",PID = "213445678912"  },
            new Customer {CustomerID = 35,CustomerName = "王维",PID = "334456789012"  },
            new Customer {CustomerID = 36,CustomerName = "赵勇",PID = "213445678912"  }
        };


        public IEnumerable<Customer> GetForFirstDropDownData()
        {
            var oo = Customers.Select(o => new Customer { CustomerID = o.CustomerID, CustomerName = o.CustomerName });
            return oo;
        }

        public IEnumerable<Customer> GetForSecondDropDownData(int customerId)
        {
            var oo = Customers.Select(o => new Customer { CustomerID = o.CustomerID, PID = o.PID })
                                .Where(w => w.CustomerID == customerId);
            return oo;
        }


        public IEnumerable<Customer> GetForGridview(int customerId)
        {
            List<Customer> _cust = new List<Customer>();
            foreach (Customer c in Customers)
            {
                if (c.CustomerID == customerId)
                    _cust.Add(new Customer { CustomerID = c.CustomerID, CustomerName = c.CustomerName, PID = c.PID, IsActived = true });
                else
                    _cust.Add(c);
            }
            return _cust;
        }

    }
}

View Code

Ok,数据准备好了，下面就可以创建网页实现相关的功能xxx.aspx:

source code:

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
        <div>
            <asp:DropDownList ID="DropDownList1" runat="server" OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged"
                AutoPostBack="true">
            </asp:DropDownList>&nbsp;&nbsp;&nbsp;&nbsp;
        <asp:DropDownList ID="DropDownList2" runat="server"></asp:DropDownList>

            <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="false" OnRowDataBound="GridView1_RowDataBound">
                <Columns>
                    <asp:TemplateField HeaderText="CustomerID">
                        <ItemTemplate>
                            <%# Eval("CustomerID") %>
                        </ItemTemplate>
                    </asp:TemplateField>
                    <asp:TemplateField HeaderText="CustomerName">
                        <ItemTemplate>
                            <%# Eval("CustomerName") %>
                        </ItemTemplate>
                    </asp:TemplateField>
                    <asp:TemplateField HeaderText="PID">
                        <ItemTemplate>
                            <%# Eval("PID") %>
                        </ItemTemplate>
                    </asp:TemplateField>
                </Columns>
            </asp:GridView>
        </div>
    </form>
</body>
</html>

View Code

xxx.aspx.cs:

source code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using Insus.NET;
using System.Data;

public partial class _Default : System.Web.UI.Page
{
    CustomerEntity ce = new CustomerEntity();

    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            Data_Binding();
        }
    }

    private void Data_Binding()
    {
        this.DropDownList1.DataSource = ce.GetForFirstDropDownData();
        this.DropDownList1.DataValueField = "CustomerID";
        this.DropDownList1.DataTextField = "CustomerName";
        this.DropDownList1.DataBind();

        this.DropDownList2.DataSource = ce.GetForSecondDropDownData(Convert.ToInt32(this.DropDownList1.SelectedItem.Value));
        this.DropDownList2.DataTextField = "PID";
        this.DropDownList2.DataBind();

        this.GridView1.DataSource = ce.GetForGridview(Convert.ToInt32(this.DropDownList1.SelectedItem.Value));
        this.GridView1.DataBind();
    }

    protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
    {
        var ddl = (DropDownList)sender;
        this.DropDownList2.DataSource = ce.GetForSecondDropDownData(Convert.ToInt32(ddl.SelectedItem.Value));
        this.DropDownList2.DataTextField = "PID";
        this.DropDownList2.DataBind();

        this.GridView1.DataSource = ce.GetForGridview(Convert.ToInt32(ddl.SelectedItem.Value));
        this.GridView1.DataBind();
    }

    protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
    {
        if (e.Row.RowType != DataControlRowType.DataRow) return;

        Customer drv = (Customer)e.Row.DataItem;

        bool isActived = (bool)drv.IsActived;

        if (isActived)
            e.Row.BackColor = System.Drawing.Color.Red;
    }
}

View Code

动画实时演示：