asp.net中gridview的查询、分页、编辑更新、删除的实例代码

1.A,运行效果图

1.B,源代码
/App_Data/sql-basic.sql

insert into category(categoryname) values('饮料')
insert into category(categoryname) values('主食')
insert into category(categoryname) values('副食')
insert into category(categoryname) values('蔬菜')

-- ================================
-- ylb:2,产品表
-- ================================
create table product
(
    productid int identity(1001,1) primary key,    --编号【PK】
    productname varchar(20),        --名称
    unitprice numeric(7,2),            --单价
    special varchar(10) check(special in('特价','非特价')),    --是否特价【C】
    categoryid int foreign key references category(categoryid)    --类别编号【FK】
)

insert into product(productname,unitprice,special,categoryid) values('可乐1',12.6,'特价',1)
insert into product(productname,unitprice,special,categoryid) values('可乐2',12.6,'非特价',1)
insert into product(productname,unitprice,special,categoryid) values('可乐3',12.6,'非特价',1)
insert into product(productname,unitprice,special,categoryid) values('可乐4',12.6,'非特价',1)
insert into product(productname,unitprice,special,categoryid) values('可乐5',12.6,'特价',1)
insert into product(productname,unitprice,special,categoryid) values('可乐6',12.6,'特价',1)
insert into product(productname,unitprice,special,categoryid) values('可乐7',12.6,'特价',1)
insert into product(productname,unitprice,special,categoryid) values('可乐8',12.6,'特价',1)
insert into product(productname,unitprice,special,categoryid) values('馒头1',12.6,'特价',2)
insert into product(productname,unitprice,special,categoryid) values('豆腐1',12.6,'特价',3)
insert into product(productname,unitprice,special,categoryid) values('冬瓜1',12.6,'特价',4)

select * from category
select productid,productname,unitprice,special,categoryid from product
</div>

,2
/App_Code/
/App_Code/DBConnection.cs

    public DBConnection()
    {
        //创建连接对象
        con = new SqlConnection("Server=.;Database=db1;Uid=sa;pwd=sa");
    }

    /// <summary>
    /// 数据连接对象
    /// </summary>
    public SqlConnection Con
    {
        get { return con; }
        set { con = value; }
    }
}
</div>

/App_Code/CategoryInfo.cs
/App_Code/CategoryOper.cs
/App_Code/ProductInfo.cs

/// <summary>
///ProductInfo 的摘要说明
///产品实体类
/// </summary>
public class ProductInfo
{
    //1,Attributes
    int productId;
    string productName;
    decimal unitprice;
    string special;
    int categoryId;

    public ProductInfo()
    {
        //
        //TODO: 在此处添加构造函数逻辑
        //
    }
    //3,

    /// <summary>
    /// 产品编号【PK】
    /// </summary>
    public int ProductId
    {
        get { return productId; }
        set { productId = value; }
    }
    /// <summary>
    /// 产品名称
    /// </summary>
    public string ProductName
    {
        get { return productName; }
        set { productName = value; }
    }
    /// <summary>
    /// 单位价格
    /// </summary>
    public decimal Unitprice
    {
        get { return unitprice; }
        set { unitprice = value; }
    }
    /// <summary>
    /// 是否为特价【C】（特价、非特价）
    /// </summary>
    public string Special
    {
        get { return special; }
        set { special = value; }
    }
    /// <summary>
    /// 类编编号【FK】
    /// </summary>
    public int CategoryId
    {
        get { return categoryId; }
        set { categoryId = value; }
    }
}
</div>

/App_Code/ProductOper.cs

using System.Data.SqlClient;
/// <summary>
///ProductOper 的摘要说明
/// </summary>
public class ProductOper
{
    /// <summary>
    /// 1,GetAll
    /// </summary>
    /// <returns></returns>
    public static IList<ProductInfo> GetAll()
    {
        IList<ProductInfo> dals = new List<ProductInfo>();
        string sql = "select productI