asp+语法教程(五)asp+的服务器端编程控件篇
2016-01-29 19:11
asp+语法教程(五)asp+的服务器端编程控件篇,asp+语法教程(五)asp+的服务器端编程控件篇
在asp+中提供了45个已经做好了的服务器控件，我们可以将他们象黑盒子一样的使用。除此以外，开发者还可以使用任何第三方开发的服务器控件
在下面的例子中，我们要用到一个通过<acme:calendar runat=server标签声明的组件，请注意，在文件的第一行必须使用<% Register % 来声明 "Acme Xml "标签的的前缀"Acme".在asp+ 文件中，将会使用这个命名的服务器控件的类的实例。
<%@ Register TagPrefix="Acme" Namespace="Acme" %
<html
<head
<link rel="stylesheet"href="intro.css"
</head
<script language="VB" runat=server
Sub SubmitBtn_Click(Sender As Object, E As EventArgs)
Message.Text = "Hi " & Name.Text & ", you selected: " & Category.SelectedItem.Text & " on: " & MyCal.Date
End Sub
</script
<body
<center
<form action="intro7.aspx" method="post" runat="server"
<asp:adrotator AdvertisementFile="ads.xml" BorderColor="black" BorderWidth=1 runat="server"/
<h3 Name: <asp:textbox id="Name" runat="server"/
Category: <asp:dropdownlist id="Category" runat=server
<asp:listitem psychology</asp:listitem
<asp:listitem business</asp:listitem
<asp:listitem popular_comp</asp:listitem
</asp:dropdownlist
<asp:button type=submit text="Lookup" OnClick="SubmitBtn_Click" runat="server"/
<p
<Acme:Calendar id="MyCal" runat=server/
<p
<asp:label id="Message" runat="server"/
</form
</center
</body
</html
声明Acme 的 文件
using System;
using System.Web;
using System.Web.UI;
using System.Collections;
namespace Acme
{
public class Calendar : Control, IPostBackEventHandler, IPostBackDataHandler
{
private String[] monthNames = new String[12];
private DateTime currentDate = DateTime.Now;
private String backColor = "#dcdcdc";
private String foreColor = "#eeeeee";
protected override void Init()
{
// Todo: We should remove the need to call this
Page.RegisterRequiresPostBack(this);
Page.RegisterPostBackScript();
currentDate = DateTime.Now;
// Todo: Hack needed because COOL doesn't support array initializers yet
monthNames[0] = "January";
monthNames[1] = "February";
monthNames[2] = "March";
monthNames[3] = "April";
monthNames[4] = "May";
monthNames[5] = "June";
monthNames[6] = "July";
monthNames[7] = "August";
monthNames[8] = "September";
monthNames[9] = "October";
monthNames[10] = "November";
monthNames[11] = "December";
}
protected override void LoadState(Object viewState)
{
// If we've done a post-back, the old date will be available to us
if (null != viewState)
{
currentDate = DateTime.Parse((String) viewState);
}
}
public void RaisePostBackEvent(String eventArgument)
{
//Page.Response.Write("RaisePostBackEvent Called!!!");
if (eventArgument == null)
{
return;
}
// Keep track of old date (for event firing purposes)
DateTime oldDate = currentDate;
// Todo: We should have post-back take two arguments: eventname and eventarguments
if (String.Compare("NavNextMonth", eventArgument, true) == 0)
{
currentDate = currentDate.AddMonths(1);
}
else if (String.Compare("NavPrevMonth", eventArgument, true) == 0)
{
currentDate = currentDate.AddMonths(-1); <
