DataGrid学习三

2022-07-15 80酷酷网 80kuku.com

　　datagrid上一例中静态填充选择框的值，但这不太适合那些值在数据库中会更改的情况。因为 select HtmlControl 也支持 IEnumerable

DataSource 属性，可以转而使用选择查询动态填充选择框，这将保证数据库和用户界面始终同步。下面的示例说明此过程。

<% Import Namespace="System.Data" %>
<% Import Namespace="System.Data.SqlClient" %>

<html>
<script language="C#" runat="server">
    SqlConnection myConnection;
    protected void Page_Load(Object Src, EventArgs E)
    {
       myConnection = new SqlConnection("user id=sa;password=;initial catalog=pubs;data source=jeff");
        if (!IsPostBack)
        {
            SqlDataAdapter myCommand = new SqlDataAdapter("select distinct State from Authors", myConnection);
            DataSet ds = new DataSet();
            myCommand.Fill(ds, "States");
            MySelect.DataSource= ds.Tables["States"].DefaultView;
            MySelect.DataBind();
        }
    }

    public void GetAuthors_Click(Object sender, EventArgs E)
    {
        String selectCmd = "select * from Authors where state = State";
        SqlDataAdapter myCommand = new SqlDataAdapter(selectCmd, myConnection);
        myCommand.SelectCommand.Parameters.Add(new SqlParameter("State", SqlDbType.NVarChar, 2));
        myCommand.SelectCommand.Parameters["State"].Value = MySelect.Value;
        DataSet ds = new DataSet();
        myCommand.Fill(ds, "Authors");
        MyDataGrid.DataSource= ds.Tables["Authors"].DefaultView;
        MyDataGrid.DataBind();
    }

</script>

<body 10.5pt 宋体">
  <form runat="server">
    <h3><font face="宋体">对 DataGrid 控件的动态参数化选择</font></h3>
    选择州:
    <select id="MySelect" DataTextField="State" runat="server"/>
    <input type="submit" OnServerClick="GetAuthors_Click" Value="获取作者" runat="server"/><p>
    <ASP:DataGrid id="MyDataGrid" runat="server"
      Width="700"
      BackColor="#ccccff"
      BorderColor="black"
      ShowFooter="false"
      CellPadding=3
      CellSpacing="0"
      Font-Name="宋体"
      Font-Size="8pt"
      HeaderStyle-BackColor="#aaaadd"
      EnableViewState="false"
    />
  </form>
</body>
</html>