通过


HtmlSelect.DataSource 属性

定义

获取或设置要绑定到 HtmlSelect 控件的信息源。

public:
 virtual property System::Object ^ DataSource { System::Object ^ get(); void set(System::Object ^ value); };
public virtual object DataSource { get; set; }
member this.DataSource : obj with get, set
Public Overridable Property DataSource As Object

属性值

IEnumerable 个或 IListSource 包含用于向此控件提供数据的值的集合。 默认值为 null

例外

指定的数据源与任一IEnumerableIListSource数据源不兼容,也不null兼容。

无法解析数据源,因为为属性和DataSourceID属性指定DataSource了一个值。

示例

下面的代码示例演示如何使用 DataSource 属性指定要绑定到 HtmlSelect 控件的信息源。

<%@ Page Language="C#" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Data.SqlClient" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >

<head>
    <title> HtmlSelect Example </title>
<script runat="server">

      void Page_Load (Object sender, EventArgs e)
      {

        // Bind the HtmlSelect control to a data source when the page is initially loaded.
        if (!IsPostBack)
        {
      
           // Open a connection to the database and run the query.
           // Note that the connection string may vary depending on your
           // database server settings. 
           string ConnectString = "server=localhost;database=pubs;integrated security=SSPI";
           string QueryString = "select * from authors";

           SqlConnection myConnection = new SqlConnection(ConnectString);
           SqlDataAdapter myCommand = new SqlDataAdapter(QueryString, myConnection);

           // Create a dataset to store the query results.
           DataSet ds = new DataSet();
           myCommand.Fill(ds, "Authors");

           // Bind the HtmlSelect control to the data source.
           Select1.DataSource = ds;
           Select1.DataTextField = "au_fname";
           Select1.DataValueField = "au_fname";
           Select1.DataBind();
        }

      }

      void Button_Click (Object sender, EventArgs e)
      {
       
         // Display the selected items. 
         Label1.Text = "You selected:";

         for (int i=0; i<=Select1.Items.Count - 1; i++)
         {
            if (Select1.Items[i].Selected)
               Label1.Text += "<br />    - " + Select1.Items[i].Text;
         }

      }

   </script>

</head>

<body>

   <form id="form1" runat="server">

      <h3> HtmlSelect Example </h3>

      Select items from the list. <br />
      Use the Control or Shift key to select multiple items. <br /><br />

      <select id="Select1"
              multiple="true" 
              runat="server"/>

      <br /><br />

      <button id="Button1"
              onserverclick="Button_Click"
              runat="server">

         Submit

      </button>

      <br /><br />

      <asp:Label id="Label1"
           runat="server"/>

   </form>

</body>

</html>
<%@ Page Language="VB" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
<%@ Import Namespace="System.Data.SqlClient" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >

<head>
    <title> HtmlSelect Example </title>
<script runat="server">

      Sub Page_Load (sender As Object, e As EventArgs)
  
        ' Bind the HtmlSelect control to a data source when the page is initially loaded.
        If Not IsPostBack Then
        
           ' Open a connection to the database and run the query.
           ' Note that the connection string may vary depending on your
           ' database server settings.
           Dim ConnectString As String = "server=localhost;database=pubs;integrated security=SSPI"
           Dim QueryString As String = "select * from authors"

           Dim myConnection As SqlConnection = New SqlConnection(ConnectString)
           Dim myCommand As SqlDataAdapter = New SqlDataAdapter(QueryString, myConnection)

           ' Create a dataset to store the query results.
           Dim ds As DataSet = New DataSet()
           myCommand.Fill(ds, "Authors")

           ' Bind the HtmlSelect control to the data source.
           Select1.DataSource = ds
           Select1.DataTextField = "au_fname"
           Select1.DataValueField = "au_fname"
           Select1.DataBind()
        
        End If

      End Sub

      Sub Button_Click (sender As Object, e As EventArgs)
        
         Dim i As Integer

         Label1.Text = "You selected:"

         For i = 0 To Select1.Items.Count - 1
         
            If Select1.Items(i).Selected Then
               Label1.Text = Label1.Text & "<br />    - " & Select1.Items(i).Text
            End If

         Next i

      End Sub

   </script>

</head>

<body>

   <form id="form1" runat="server">

      <h3> HtmlSelect Example </h3>

      Select items from the list. <br />
      Use the Control or Shift key to select multiple items. <br /><br />

      <select id="Select1"
              multiple="true" 
              runat="server"/>

      <br /><br />

      <button id="Button1"
              onserverclick="Button_Click"
              runat="server">

         Submit

      </button>

      <br /><br />

      <asp:Label id="Label1"
           runat="server"/>

   </form>

</body>

</html>

注解

使用 DataSource 属性指定要绑定到控件的 HtmlSelect 数据源。 数据源必须是实现 System.Collections.IEnumerable 接口(例如 System.Data.DataViewSystem.Collections.ArrayListSystem.Collections.Generic.List<T>)或接口的 IListSource 集合。 设置 DataSource 属性时,必须手动编写代码来执行数据绑定。

如果数据源包含多个数据集(例如 System.Data.DataSet 具有多个表的对象),请使用 DataMember 属性指定要绑定到控件的数据集。

可以通过分别设置DataTextField控件和属性来指定要绑定到ListItem.TextListItem.Value控件中每个项的数据源中的哪些字段和DataValueField属性。

或者,可以使用 DataSourceID 该属性自动绑定到数据源控件所表示的数据源。 设置 DataSourceID 属性时,数据列表控件会自动绑定到指定的数据源控件。 无需编写显式调用 DataBind 该方法的代码。

如果为 DataSource 属性和 DataSourceID 属性指定了值,则 ASP.NET 无法解析数据源并 System.Web.HttpException 引发异常。

适用于

另请参阅