后台两个方法
 protected void search(object sender, EventArgs e)
        {
            GridView1.DataSourceID = this.ObjectDataSource1.ID;
            GridView1.DataBind();
        }
        public DataTable searchcontact()
        {
            SqlConnection conn = new SqlConnection();
            conn.ConnectionString = " Data Source=DELL-PC;Initial Catalog=yangweiQ;Integrated Security=True";
            conn.Open();
            string str="select* from admin";
            SqlDataAdapter  sda=new SqlDataAdapter();
            SqlCommand comm=new SqlCommand(str,conn);
            DataTable da=new DataTable();
            sda.Fill(da);
            conn.Close();
            return da;
}前台    <asp:GridView ID="GridView1" runat="server">
        </asp:GridView>
        <asp:Button ID="Button1" runat="server" Text="Button" OnClick="search" />
        <asp:ObjectDataSource ID="ObjectDataSource1" runat="server" TypeName="WebForm1" SelectMethod="searchcontact">
        </asp:ObjectDataSource>