ASP.NET Tutorial/ADO.net Database/DataRows

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DataRow States and DataRow Versions

File: App_Code\Product.cs
using System;
using System.Data;
using System.Data.SqlClient;
using System.Web;
using System.Web.Configuration;
public class Product
{
    private SqlDataAdapter dad = new SqlDataAdapter();
    public DataTable GetAll()
    {
        return (DataTable)HttpContext.Current.Session["ProductsToEdit"];
    }
    public void Update(int id, string title, string director)
    {
        DataTable products = (DataTable)HttpContext.Current.Session["ProductstoEdit"];
        DataRow rowToEdit = products.Rows.Find(id);
        rowToEdit["title"] = title;
        rowToEdit["director"] = director;
    }
    public void RejectChanges()
    {
        DataTable products = (DataTable)HttpContext.Current.Session["ProductstoEdit"];
        products.RejectChanges();
    }
    public void AcceptChanges()
    {
        DataTable products = (DataTable)HttpContext.Current.Session["ProductstoEdit"];
        dad.Update(products);
        products.AcceptChanges();    }
    public Product()
    {
        string connectionString = WebConfigurationManager.ConnectionStrings["Products"].ConnectionString;
        dad = new SqlDataAdapter("SELECT Id,Title,Director FROM Products", connectionString);
        SqlCommandBuilder builder = new SqlCommandBuilder(dad);
        dad.UpdateBatchSize = 0;
        HttpContext context = HttpContext.Current;
        if (context.Session["ProductsToEdit"] == null)
        {
            DataTable dtblProducts = new DataTable();
            dad.Fill(dtblProducts);
            dtblProducts.PrimaryKey = new DataColumn[] { dtblProducts.Columns["Id"] };
            context.Session["ProductsToEdit"] = dtblProducts;
        }
    }
}

File: Web.config
<configuration>
  <connectionStrings>
    <add name="Products" 
         connectionString="Data Source=.\SQLEXPRESS;
         AttachDbFilename=|DataDirectory|MyDatabase.mdf;Integrated Security=True;User Instance=True" />
  </connectionStrings>
</configuration>
File: ShowProduct.aspx
<%@ Page Language="C#" %>
<%@ Import Namespace="System.Data" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
    protected void btnReject_Click(object sender, EventArgs e)
    {
        Product product = new Product();
        product.RejectChanges();
        grdProducts.DataBind();
    }
    protected void btnAccept_Click(object sender, EventArgs e)
    {
        Product product = new Product();
        product.AcceptChanges();
        grdProducts.DataBind();
    }
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
    <title>Show Product</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    <h1>Edit Products</h1>
    <asp:GridView
        id="grdProducts"
        DataSourceID="srcProducts"
        DataKeyNames="Id"
        AutoGenerateEditButton="true"
        Runat="server">
        <Columns>
        <asp:TemplateField>
        <ItemTemplate>
        <%# ((DataRowView)Container.DataItem).Row.RowState %>
        </ItemTemplate>
        </asp:TemplateField>
        </Columns>
    </asp:GridView>
    <br />
    <asp:Button
        id="btnReject"
        Text="Reject Changes"
        OnClick="btnReject_Click"
        Runat="server" />
    <asp:Button
        id="btnAccept"
        Text="Accept Changes"
        OnClick="btnAccept_Click"
        Runat="server" />
    <asp:ObjectDataSource
        id="srcProducts"
        TypeName="Product"
        SelectMethod="GetAll"
        UpdateMethod="Update"
        Runat="server" />
    </div>
    </form>
</body>
</html>


Selecting DataRows

<%@ Page Language="C#" %>
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Data.SqlClient" %>
<%@ Import Namespace="System.Web.Configuration" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN""http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
    protected void btnSearch_Click(object sender, EventArgs e)
    {
        DataTable dtblProducts = (DataTable)Cache["ProductsToFilter"];
        if (dtblProducts == null)
        {
            dtblProducts = GetProductsFromDB();
            Cache["ProductsToFilter"] = dtblProducts;
        }
        string filter = String.Format("Title LIKE "{0}*"", txtTitle.Text);
        DataRow[] rows = dtblProducts.Select(filter, "Title");
        grdProducts.DataSource = rows;
        grdProducts.DataBind();
    }
    private DataTable GetProductsFromDB()
    {
        string connectionString = WebConfigurationManager.ConnectionStrings["Products"].ConnectionString;
        SqlDataAdapter dad = new SqlDataAdapter("SELECT Title, Director FROM Products", connectionString);
        DataTable dtblProducts = new DataTable();
        dad.Fill(dtblProducts);
        return dtblProducts;
    }
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
    <title>Show DataTable Select</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    <asp:TextBox
        id="txtTitle"
        Tooltip="Search"
        Runat="server" />
    <asp:Button
        id="btnSearch"
        Text="Search"
        Runat="server" OnClick="btnSearch_Click" />

    <hr />
    <asp:GridView
        id="grdProducts"
        AutoGenerateColumns="false"
        Runat="server">
        <Columns>
        <asp:TemplateField HeaderText="Title">
        <ItemTemplate>
            <%# ((DataRow)Container.DataItem)["Title"] %>
        </ItemTemplate>
        </asp:TemplateField>
        <asp:TemplateField HeaderText="Director">
        <ItemTemplate>
            <%# ((DataRow)Container.DataItem)["Director"] %>
        </ItemTemplate>
        </asp:TemplateField>
        </Columns>
        </asp:GridView>
    </div>
    </form>
</body>
</html>
File: Web.config
<configuration>
  <connectionStrings>
    <add name="Products" 
         connectionString="Data Source=.\SQLEXPRESS;
         AttachDbFilename=|DataDirectory|MyDatabase.mdf;Integrated Security=True;User Instance=True" />
  </connectionStrings>
</configuration>


The DataView object represents an in-memory database view.

You can use a DataView object to create a sortable, filterable view of a DataTable.
<%@ Page Language="C#" %>
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Data.SqlClient" %>
<%@ Import Namespace="System.Web.Configuration" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
    void Page_Load()
    {
        if (Session["ProductsToSort"] == null)
        {
            string connectionString = WebConfigurationManager.ConnectionStrings["Products"].ConnectionString;
            SqlDataAdapter dad = new SqlDataAdapter("SELECT Id,Title,Director FROM Products", connectionString);
            DataTable dtblProducts = new DataTable();
            dad.Fill(dtblProducts);
            Session["ProductsToSort"] = dtblProducts.DefaultView;
        }
        if (!Page.IsPostBack)
            BindProducts();
    }
    void BindProducts()
    {
        grdProducts.DataSource = Session["ProductsToSort"];
        grdProducts.DataBind();
    }
    protected void grdProducts_Sorting(object sender, GridViewSortEventArgs e)
    {
        DataView dvwProducts = (DataView)Session["ProductsToSort"];
        dvwProducts.Sort = e.SortExpression;
        BindProducts();
    }
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
    <title>Show DataView</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    <asp:GridView
        id="grdProducts"
        AllowSorting="true"
        OnSorting="grdProducts_Sorting"
        Runat="server" />
    </div>
    </form>
</body>
</html>

File: Web.config
<configuration>
  <connectionStrings>
    <add name="Products" 
         connectionString="Data Source=.\SQLEXPRESS;
         AttachDbFilename=|DataDirectory|MyDatabase.mdf;Integrated Security=True;User Instance=True" />
  </connectionStrings>
</configuration>
Источник — «http://nfex.ru/index.php?title=ASP.NET_Tutorial/ADO.net_Database/DataRows&oldid=2693»