ASP.NET Tutorial/ADO.net Database/DataSet — различия между версиями

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Текущая версия на 11:56, 26 мая 2010

Create DataSet by your own

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="DataSetBinding" %>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <asp:ListBox ID="lstUser" runat="server" Height="152px" Width="192px"></asp:ListBox></div>
    </form>
</body>
</html>

File: Default.aspx.cs

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
public partial class DataSetBinding : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        DataSet dsInternal = new DataSet();
        dsInternal.Tables.Add("Users");
        dsInternal.Tables["Users"].Columns.Add("Name");
        dsInternal.Tables["Users"].Columns.Add("Country");
        DataRow rowNew = dsInternal.Tables["Users"].NewRow();
        rowNew["Name"] = "A";
        rowNew["Country"] = "USA";
        dsInternal.Tables["Users"].Rows.Add(rowNew);
        rowNew = dsInternal.Tables["Users"].NewRow();
        rowNew["Name"] = "B";
        rowNew["Country"] = "Canada";
        dsInternal.Tables["Users"].Rows.Add(rowNew);
        rowNew = dsInternal.Tables["Users"].NewRow();
        rowNew["Name"] = "C";
        rowNew["Country"] = "Japan";
        dsInternal.Tables["Users"].Rows.Add(rowNew);
        lstUser.DataSource = dsInternal.Tables["Users"];
        lstUser.DataTextField = "Name";
        lstUser.DataSource = dsInternal;
        lstUser.DataMember = "Users";
        lstUser.DataTextField = "Name";
        this.DataBind();
    }
}


Fill a DataSet

<%@ Page language="c#" Inherits="FillDataSet" CodeFile="Default.aspx.cs" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN" >
<HTML>
  <HEAD>
    <title>FillDataSet</title>
    </HEAD>
  <body>
    <form id="Form1" method="post" runat="server">
      <TABLE id="Table1" width="100%">
        <TR>
          <TD>
            <asp:Repeater id="Repeater1" runat="server">
              <HeaderTemplate>
                <h2>Repeater</h2>
              </HeaderTemplate>
              <ItemTemplate>
                <li>
                  <%# DataBinder.Eval(Container.DataItem, "TitleOfCourtesy") %>
                  <b>
                    <%# DataBinder.Eval(Container.DataItem, "LastName") %>
                  </b>,
                  <%# DataBinder.Eval(Container.DataItem, "FirstName") %>
                </li>
              </ItemTemplate>
            </asp:Repeater></TD>
          <TD>
            <H2>foreach approach</H2>
            <asp:Literal id="HtmlContent" runat="server"></asp:Literal></TD>
        </TR>
      </TABLE>
    </form>
  </body>
</HTML>
File: Default.aspx.cs
using System;
using System.Collections;
using System.ruponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using System.Text;
using System.Data.SqlClient;
public partial class FillDataSet : System.Web.UI.Page
{
  protected void Page_Load(object sender, System.EventArgs e)
  {
    string connectionString = "Data Source=localhost;Initial Catalog=Northwind;Integrated Security=SSPI";
    SqlConnection con = new SqlConnection(connectionString);
    string sql = "SELECT * FROM Employees";
    SqlDataAdapter da = new SqlDataAdapter(sql, con);
    DataSet ds = new DataSet();
    da.Fill(ds, "Employees");
    StringBuilder htmlStr = new StringBuilder("");
    foreach (DataRow dr in ds.Tables["Employees"].Rows)
    {
      htmlStr.Append("<li>");
      htmlStr.Append(dr["TitleOfCourtesy"].ToString());
      htmlStr.Append(" <b>");
      htmlStr.Append(dr["LastName"].ToString());
      htmlStr.Append("</b>, ");
      htmlStr.Append(dr["FirstName"].ToString());
      htmlStr.Append("</li>");
    }
    HtmlContent.Text = htmlStr.ToString();
    Repeater1.DataSource = ds;
    Repeater1.DataMember = "Employees";
    Repeater1.DataBind();
  }
}


Fill DataSet with SqlDataAdapter

<%@ Page Language="C#" %>
<%@ import Namespace="System.Data" %>
<%@ import Namespace="System.Data.SqlClient" %>
<script runat="server">
    void Page_Load(object sender, EventArgs e)
    {
       string ConnectionString = Convert.ToString(ConfigurationSettings.AppSettings["MSDEConnectString"]);
       string CommandText = "SELECT * FROM Publisher";
       SqlConnection myConnection = new SqlConnection(ConnectionString);
       SqlCommand myCommand = new SqlCommand(CommandText, myConnection);
       SqlDataAdapter myAdapter = new SqlDataAdapter();
       myAdapter.SelectCommand = myCommand;
       DataSet myDataSet = new DataSet();
       try {
          myConnection.Open();
          myAdapter.Fill(myDataSet);
       } catch (Exception ex) {
          throw (ex);
       } finally {
          myConnection.Close();
       }
       myGrid.DataSource = myDataSet;
       myGrid.DataBind();
    }
</script>
<html>
<body>
    <form runat="server">
        <asp:DataGrid id="myGrid" runat="server"></asp:DataGrid>
    </form>
</body>
</html>
File: Web.config
<configuration>
    <appSettings>
      <add key="MSDEConnectString"
           value="server=(local)\YourDatabase;database=Books;uid=YourID;pwd=letmein;" />
    
    </appSettings>
</configuration>


Iterating Through A DataSet

<%@ Page Language="C#" %>
<%@ import Namespace="System.Data" %>
<%@ import Namespace="System.Data.SqlClient" %>
<script runat="server">
    void Page_Load(object sender, EventArgs e)
    {
        string ConnectionString = Convert.ToString(ConfigurationSettings.AppSettings["MSDEConnectString"]);
        string CommandText = "SELECT AuthorName, AuthorCity, AuthorContact_Email, AuthorWebsite FROM Author";
        SqlConnection myConnection = new SqlConnection(ConnectionString);
        SqlCommand myCommand = new SqlCommand(CommandText, myConnection);
       SqlDataAdapter myAdapter = new SqlDataAdapter();
       myAdapter.SelectCommand = myCommand;
       DataSet myDataSet = new DataSet();
       try
       {
          myConnection.Open();
          myAdapter.Fill(myDataSet, "Author");
       } catch (Exception ex) {
          throw (ex);
       } finally
       {
          myConnection.Close();
       }
       for (int i=0; i<=myDataSet.Tables["Author"].Rows.Count-1; i++)
       {
          Author p = new Author();
          p.Name = myDataSet.Tables["Author"].Rows[i]["AuthorName"].ToString();
          p.City = myDataSet.Tables["Author"].Rows[i]["AuthorCity"].ToString();
          p.Email = myDataSet.Tables["Author"].Rows[i]["AuthorContact_Email"].ToString();
          p.Website = myDataSet.Tables["Author"].Rows[i]["AuthorWebsite"].ToString();
          Label1.Text += p.ToString();
       }
    }

    public class Author
    {
        public string Name;
        public string City;
        public string Email;
        public string Website;
        public Author()
        {}
        public string ToString()
        {
            string description = "";
            description = "Name : " + this.Name + "<br />";
            description += "City : " + this.City + "<br />";
            description += "Contact : <a href=mailto:" + this.Email + ">" + this.Email + "</a><br/>";
            description += "Homesite : <a href="" + this.Website + "">" + this.Website + "</a><br/><br/>";
            return description;
        }
    }
</script>
<html>
<body>
    <asp:Label id="Label1" runat="server"></asp:Label>
</body>
</html>

File: DataSet
<configuration>
    <appSettings>
      <add key="MSDEConnectString"
           value="server=(local)\YourDatabase;database=Books;uid=YourID;pwd=letmein;" />
    
    </appSettings>
</configuration>


Iterating Through A DataSet from MySQL database

<%@ Page Language="C#" %>
<%@ import Namespace="System.Data" %>
<%@ import Namespace="System.Data.Odbc" %>
<script runat="server">
    void Page_Load(object sender, EventArgs e)
    {
        string ConnectionString = Convert.ToString(ConfigurationSettings.AppSettings["MySQLConnectString"]);
        string CommandText = "SELECT AuthorName, AuthorCity, AuthorContact_Email, AuthorWebsite FROM Author";
        OdbcConnection myConnection = new OdbcConnection(ConnectionString);
        OdbcCommand myCommand = new OdbcCommand(CommandText, myConnection);
        OdbcDataAdapter myAdapter = new OdbcDataAdapter();
        myAdapter.SelectCommand = myCommand;
        DataSet myDataSet = new DataSet();
        try {
          myConnection.Open();
          myAdapter.Fill(myDataSet, "Author");
       } catch (Exception ex) {
          throw (ex);
       } finally {
          myConnection.Close();
       }
       for (int i=0; i<=myDataSet.Tables["Author"].Rows.Count-1; i++)
       {
          Author p = new Author();
          p.Name = myDataSet.Tables["Author"].Rows[i]["AuthorName"].ToString();
          p.City = myDataSet.Tables["Author"].Rows[i]["AuthorCity"].ToString();
          p.Email = myDataSet.Tables["Author"].Rows[i]["AuthorContact_Email"].ToString();
          p.Website = myDataSet.Tables["Author"].Rows[i]["AuthorWebsite"].ToString();
          Label1.Text += p.ToString();
       }
    }
    public class Author
    {
        public string Name;
        public string City;
        public string Email;
        public string Website;
        public Author()
        {}
        public string ToString()
        {
            string description = "";
            description = "Name : " + this.Name + "<br />";
            description += "City : " + this.City + "<br />";
            description += "Contact : <a href=mailto:" + this.Email + ">" + this.Email + "</a><br/>";
            description += "Homesite : <a href="" + this.Website + "">" + this.Website + "</a><br/><br/>";
            return description;
        }
    }
</script>
<html>
<head>
</head>
<body>
    <asp:Label id="Label1" runat="server"></asp:Label>
</body>
</html>
File: Web.config
<configuration>
    <appSettings>
      <add key="MySQLConnectString"
           value="driver={MySQL ODBC 3.51 Driver};server=localhost;database=Books;uid=YourID;pwd=letmein;" />
    </appSettings>
</configuration>


List Binding To A DataSet

<%@ Page Language="C#" %>
<%@ import Namespace="System.Data" %>
<%@ import Namespace="System.Data.SqlClient" %>
<script runat="server">
    DataSet myDataSet = new DataSet();
    void Page_Load(object sender, EventArgs e)
    {
       string ConnectionString = Convert.ToString(ConfigurationSettings.AppSettings["MSDEConnectString"]);
       string CommandText = "SELECT * FROM Publisher";
       SqlConnection myConnection = new SqlConnection(ConnectionString);
       SqlCommand myCommand = new SqlCommand(CommandText, myConnection);
       SqlDataAdapter myAdapter = new SqlDataAdapter();
       myAdapter.SelectCommand = myCommand;
       try {
          myConnection.Open();
          myAdapter.Fill(myDataSet, "Publisher");
       } catch (Exception ex) {
          throw (ex);
       } finally {
          myConnection.Close();
       }
       Page.DataBind();
    }
</script>
<html>
<body>
    <form runat="server">
        <h2>A CheckBoxList</h2>
        
            <asp:CheckBoxList id="CheckBoxList1" runat="server" BorderWidth="2px" BorderStyle="Dotted" DataValueField="PublisherID" DataTextField="PublisherName" DataSource="<%# myDataSet.Tables["Publisher"] %>"></asp:CheckBoxList>
        
        <h2>A RadioButtonList</h2>
        
            <asp:RadioButtonList id="RadioButtonList1" runat="server" DataValueField="PublisherID" DataTextField="PublisherName" DataSource="<%# myDataSet.Tables["Publisher"] %>"></asp:RadioButtonList>
        
        <h2>A DropDownList</h2>
        
            <asp:DropDownList id="DropDownList1" runat="server" DataValueField="PublisherID" DataTextField="PublisherName" DataSource="<%# myDataSet.Tables["Publisher"] %>"></asp:DropDownList>
        
        <h2>A ListBox </h2>
        
            <asp:ListBox id="ListBox1" runat="server" DataValueField="PublisherID" DataTextField="PublisherName" DataSource="<%# myDataSet.Tables["Publisher"] %>" Rows="5"></asp:ListBox>
        
    </form>
</body>
</html>

File: Web.config
<configuration>
    <appSettings>
        <add key="MSDEConnectString" value="server=(local)\YourDatabase;database=Books;uid=YourID;pwd=letmein;" />
    </appSettings>
</configuration>


Pulling Single Values From Dataset Bounded Lists

<%@ Page Language="C#" %>
<%@ import Namespace="System.Data" %>
<%@ import Namespace="System.Data.SqlClient" %>
<script runat="server">
    DataSet myDataSet = new DataSet();
    void BuildDataSetTable(string commandText, string tableName)
    {
       string ConnectionString = Convert.ToString(ConfigurationSettings.AppSettings["MSDEConnectString"]);
       SqlConnection myConnection = new SqlConnection(ConnectionString);
       SqlCommand myCommand = new SqlCommand(commandText, myConnection);
       SqlDataAdapter myAdapter = new SqlDataAdapter(myCommand);
       try {
          myConnection.Open();
          myAdapter.Fill(myDataSet, tableName);
       } catch (Exception ex) {
          throw(ex);
       } finally {
          myConnection.Close();
       }
    }
    void Page_Load(object sender, EventArgs e) {
       if (!(Page.IsPostBack)) 
       {
          string SelectPublisher = "SELECT PublisherID, PublisherName From Publisher";
          BuildDataSetTable(SelectPublisher, "Publisher");
          Label1.Text = "Select a Publisher";
          DropDownList1.DataBind();
          RadioButtonList1.DataBind();
          ListBox1.DataBind();
       }
    }
    void RadioButtonList1_SelectedIndexChanged(object sender, EventArgs e) {
          string SelectBook = "SELECT * FROM Book WHERE BookPublisherID=" + RadioButtonList1.SelectedItem.Value;
          BuildDataSetTable(SelectBook, "Book");
          DataGrid1.DataBind();
    }
    void DropDownList1_SelectedIndexChanged(object sender, EventArgs e) {
          string SelectBook = "SELECT * FROM Book WHERE BookPublisherID=" + DropDownList1.SelectedItem.Value;
          BuildDataSetTable(SelectBook, "Book");
          DataGrid1.DataBind();
    }
    void ListBox1_SelectedIndexChanged(object sender, EventArgs e) {
          string SelectBook = "SELECT * FROM Book WHERE BookPublisherID=" + ListBox1.SelectedItem.Value;
          BuildDataSetTable(SelectBook, "Book");
          DataGrid1.DataBind();
    }
</script>
<html>
<head>
</head>
<body>
    <form runat="server">
    
        <asp:RadioButtonList id="RadioButtonList1" runat="server" DataSource="<%# myDataSet.Tables["Publisher"] %>" DataTextField="PublisherName" DataValueField="PublisherID" AutoPostBack="True" OnSelectedIndexChanged="RadioButtonList1_SelectedIndexChanged"></asp:RadioButtonList>
    
    <h2>A DropDownList
    </h2>
    
        <asp:DropDownList id="DropDownList1" runat="server" DataSource="<%# myDataSet.Tables["Publisher"] %>" DataTextField="PublisherName" DataValueField="PublisherID" AutoPostBack="True" OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged"></asp:DropDownList>
    
    <h2>A ListBox
    </h2>
    
        <asp:ListBox id="ListBox1" runat="server" DataSource="<%# myDataSet.Tables["Publisher"] %>" DataTextField="PublisherName" DataValueField="PublisherID" AutoPostBack="True" OnSelectedIndexChanged="ListBox1_SelectedIndexChanged"></asp:ListBox>
    
    
        <asp:Label id="Label1" runat="server"></asp:Label>
    
    
        <asp:DataGrid id="DataGrid1" runat="server" DataSource="<%# myDataSet.Tables["Book"] %>" BorderStyle="None" BorderWidth="1px" BorderColor="#CC9966" BackColor="White" CellPadding="4">
            <FooterStyle forecolor="#330099" backcolor="#FFFFCC"></FooterStyle>
            <HeaderStyle font-bold="True" forecolor="#FFFFCC" backcolor="#990000"></HeaderStyle>
            <PagerStyle horizontalalign="Center" forecolor="#330099" backcolor="#FFFFCC"></PagerStyle>
            <SelectedItemStyle font-bold="True" forecolor="#663399" backcolor="#FFCC66"></SelectedItemStyle>
            <ItemStyle forecolor="#330099" backcolor="White"></ItemStyle>
        </asp:DataGrid>
    
    </form>
</body>
</html>
File: Web.config
<configuration>
    <appSettings>
        <add key="MSDEConnectString" value="server=(local)\YourDatabase;database=Books;uid=YourID;pwd=letmein;" />
    </appSettings>
</configuration>


Serialization capabilities of DataSet

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" 
    Inherits="Default"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>Test DataSet Serialization</title>
</head>
<body>
    <div id="pageContent">
        <form id="form1" runat="server">
            <table>
                <tr>
                    <td><asp:Button Text="Serialize as XML" runat="server" ID="XmlButton" OnClick="XmlButton_Click" Width="200px" /></td>
                    <td><asp:Label ID="XmlSize" runat="server" /></td>
                </tr>
                <tr>
                    <td><asp:Button Text="Serialize as Binary" runat="server" ID="BinButton" OnClick="BinButton_Click" Width="200px" /></td>
                    <td><asp:Label ID="BinSize" runat="server" /></td>
                </tr>
            </table>
        </form>
    </div>
</body>
</html>
File: Default.aspx.cs
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Data.SqlClient;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.IO;
using System.Runtime.Serialization.Formatters.Binary;

public partial class Default : System.Web.UI.Page
{
  private string XmlFile = @"c:\serial.xml";
  private string BinFile = @"c:\serial.bin";
  private DataSet GetData()
  {
    DataSet ds = new DataSet();
    SqlDataAdapter adapter = new SqlDataAdapter(
      "SELECT * FROM [order details]",
      ConfigurationManager.ConnectionStrings["NorthwindConnectionString"].ConnectionString);
    adapter.Fill(ds);
    return ds;
  }
  protected void XmlButton_Click(object sender, EventArgs e)
  {
    DataSet ds = GetData();
    ds.RemotingFormat = SerializationFormat.Xml;
    StreamWriter writer = new StreamWriter(XmlFile);
    BinaryFormatter bin = new BinaryFormatter();
    bin.Serialize(writer.BaseStream, ds);
    writer.Close();
    FileInfo fi = new FileInfo(XmlFile);
    XmlSize.Text = (fi.Length/1024).ToString() + " KB";
  }
  protected void BinButton_Click(object sender, EventArgs e)
  {
    DataSet ds = GetData();
    ds.RemotingFormat = SerializationFormat.Binary;
    StreamWriter writer = new StreamWriter(BinFile);
    BinaryFormatter bin = new BinaryFormatter();
    bin.Serialize(writer.BaseStream, ds);
    writer.Close();
    FileInfo fi = new FileInfo(BinFile);
    BinSize.Text = (fi.Length/1024).ToString() + " KB";
  }
}


The DataSet object represents an in-memory database.

A single DataSet can contain one or many DataTable objects. 
You can define parent/child relationships between the DataTable objects contained in a DataSet.
<%@ 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 (!Page.IsPostBack)
            BuildTree();
    }
    void BuildTree()
    {
        string connectionString = WebConfigurationManager.ConnectionStrings["Products"].ConnectionString;
        SqlConnection con = new SqlConnection(connectionString);
        SqlDataAdapter dadCategories = new SqlDataAdapter("SELECT Id,Name FROM ProductCategories", con);
        SqlDataAdapter dadProducts = new SqlDataAdapter("SELECT Title,CategoryId FROM Products", con);
        DataSet dstProducts = new DataSet();
        using (con)
        {
            con.Open();
            dadCategories.Fill(dstProducts, "Categories");
            dadProducts.Fill(dstProducts, "Products");
        }
        dstProducts.Relations.Add("Children", dstProducts.Tables["Categories"].Columns["Id"], dstProducts.Tables["Products"].Columns["CategoryId"]);
        foreach (DataRow categoryRow in dstProducts.Tables["Categories"].Rows)
        {
            string name = (string)categoryRow["Name"];
            TreeNode catNode = new TreeNode(name);
            TreeView1.Nodes.Add(catNode);
            DataRow[] productRows = categoryRow.GetChildRows("Children");
            foreach (DataRow productRow in productRows)
            {
                string title = (string)productRow["Title"];
                TreeNode productNode = new TreeNode(title);
                catNode.ChildNodes.Add(productNode);
            }
        }
    }
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
    <title>Show DataSet</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    <asp:TreeView
        id="TreeView1"
        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>


Use OleDbDataAdapter to fill DataSet

<%@ Page Language="C#" %>
<%@ import Namespace="System.Data" %>
<%@ import Namespace="System.Data.OleDb" %>
<script runat="server">
    void Page_Load(object sender, EventArgs e)
    {
       string ConnectionString = Convert.ToString(ConfigurationSettings.AppSettings["AccessConnectString"]);
       string CommandText = "SELECT * FROM Publisher";
    
       OleDbConnection myConnection = new OleDbConnection(ConnectionString);
       OleDbCommand myCommand = new OleDbCommand(CommandText, myConnection);
    
       OleDbDataAdapter myAdapter = new OleDbDataAdapter();
    
       myAdapter.SelectCommand = myCommand;
    
       DataSet myDataSet = new DataSet();
    
       try {
          myConnection.Open();
    
          myAdapter.Fill(myDataSet);
    
       } catch (Exception ex) {
          throw (ex);
       } finally {
          myConnection.Close();
       }
       myGrid.DataSource = myDataSet;
       myGrid.DataBind();
    
    }
</script>
<html>
<head>
</head>
<body>
    <form runat="server">
        <asp:DataGrid id="myGrid" runat="server"></asp:DataGrid>
    </form>
</body>
</html>
File: 
<configuration>
    <appSettings>
      <add key="AccessConnectString"
           value="Provider=Microsoft.Jet.OLEDB.4.0; Data Source=Books.mdb;" />
    </appSettings>
</configuration>