欢迎光临
我们一直在努力
当前位置：IDC资讯中心 > 网络编程 > ASP教程 > 正文

asp+语法教程(五)asp+的服务器端编程控件篇_asp教程

2007-08-23 分类：ASP教程 阅读(556) 评论(0)
建站超值云服务器，限时71元/月

使用定制的服务器控件
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 doesnt 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 weve 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);
}
else
{
int daySelected = Int32.Parse(eventArgument);
currentDate = new DateTime(currentDate.Year, currentDate.Month, daySelected);
}
}

protected override Object SaveState()
{
// Save CurrentDate out as view state for postback scenarios

return currentDate.ToString();
}

protected override void Render(HtmlTextWriter output)
{
//Response.Write(Page.Request.UserAgent);

if (Page.Request.UserAgent.IndexOf("MSIE 5.5") != -1)
RenderUpLevel(output);
else
RenderDownLevel(output);
}

protected void RenderUpLevel(HtmlTextWriter output)
{
output.WriteLine("<input name=" + UniqueID + "_CurrentDate id=" + UniqueID + "_CurrentDate type=hidden>");
output.WriteLine("<span id=" + UniqueID + "></span>");
output.WriteLine("<script language=jscript>drawcalendar(" + UniqueID + ", " + Int32.Format(currentDate.Year, null) + "/" + Int32.Format(currentDate.Month, null) + "/" + Int32.Format(currentDate.Day, null) + ");</script>");
}

protected override void PreRender()
{
String DHTMLFunction = "";

DHTMLFunction += "<script language=JavaScript> \n";
DHTMLFunction += " function drawcalendar(calname, newDate) \n";
DHTMLFunction += " { \n";
DHTMLFunction += " var CurrentDate = new Date(newDate);\n";
DHTMLFunction += " var MonthArray = new Array(January, February, March, April, May, June, July, August, September, October, November, December);\n";
DHTMLFunction += " var MonthDays = new Array(31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31);\n";
DHTMLFunction += " var calText;\n";
DHTMLFunction += " calText = <table bgcolor=#dcdcdc border=0 height=190 valign=top>;\n";
DHTMLFunction += " calText = calText + <tr><td>;\n";
DHTMLFunction += " calText = calText + <center>;\n";
DHTMLFunction += " calText = calText + \"<a href=javascript:drawcalendar(\\\"\" + calname + \"\\\", \\\"\" + CurrentDate.getFullYear() + \"/\" + CurrentDate.getMonth() + \"/\" + CurrentDate.getDate() + \"\\\")>\";\n";
DHTMLFunction += " calText = calText + <img src=/quickstart/aspplus/images/left4.gif width=11 height=11 border=0></a>;\n";
DHTMLFunction += " calText = calText + <b> + MonthArray[CurrentDate.getMonth()] + + CurrentDate.getFullYear() + </b>;\n";
DHTMLFunction += " calText = calText + \" <a href=javascript:drawcalendar(\\\"\" + calname + \"\\\", \\\"\" + CurrentDate.getFullYear() + \"/\" + (CurrentDate.getMonth() + 2) + \"/\" + CurrentDate.getDate() + \"\\\")>\";\n";
DHTMLFunction += " calText = calText + <IMG SRC=/quickstart/aspplus/images/right4.gif width=11 height=11 border=0></a>;\n";
DHTMLFunction += " calText = calText + </center>;\n";
DHTMLFunction += " calText = calText + </td></tr>;\n";
DHTMLFunction += " calText = calText + <tr valign=top><td valign=top>;\n";
DHTMLFunction += " calText = calText + <table border=1 bgcolor=#eeeeee height=160>;\n";
DHTMLFunction += " calText = calText + <tr height=20>;\n";
DHTMLFunction += " calText = calText + <td align=right width=23> Sun </td>;\n";
DHTMLFunction += " calText = calText + <td align=right width=23> Mon </td>;\n";
DHTMLFunction += " calText = calText + <td align=right width=23> Tue </td>;\n";
DHTMLFunction += " calText = calText + <td align=right width=23> Wed </td>;\n";
DHTMLFunction += " calText = calText + <td align=right width=23> Thu </td>;\n";
DHTMLFunction += " calText = calText + <td align=right width=23> Fri </td>;\n";
DHTMLFunction += " calText = calText + <td align=right width=23> Sat </td>;\n";
DHTMLFunction += " calText = calText + </tr>;\n";
DHTMLFunction += " calText = calText + <tr>;\n";
DHTMLFunction += " var numDays = MonthDays[CurrentDate.getMonth()];\n";
DHTMLFunction += " var firstDay = new Date(1999, 8, 1).getDay();\n";
DHTMLFunction += " for (var x=0; x<firstDay; x++)\n";
DHTMLFunction += " {\n";
DHTMLFunction += " calText = calText + <td align=right width=23></td>\n";
DHTMLFunction += " }\n";
DHTMLFunction += " for (var x=1; x<=numDays; x++) \n";
DHTMLFunction += " { \n";
DHTMLFunction += " if (CurrentDate.getDate() == x) \n";
DHTMLFunction += " { \n";
DHTMLFunction += " calText = calText + <td align=right width=23>;\n";
DHTMLFunction += " calText = calText + <font color=red><b><u> + x + </u></b></font>;\n";
DHTMLFunction += " calText = calText + </td>;\n";
DHTMLFunction += " }\n";
DHTMLFunction += " else \n";
DHTMLFunction += " { \n";
DHTMLFunction += " calText = calText + <td align=right width=23>;\n";
DHTMLFunction += " calText = calText + \"<a href=javascript:drawcalendar(\\\"\" + calname + \"\\\", \\\"\" + CurrentDate.getFullYear() + \"/\" + (CurrentDate.getMonth()+1) + \"/\" + x + \"\\\")>\" + x + \"</a>\";";
DHTMLFunction += " calText = calText + </td>;\n";
DHTMLFunction += " }\n";
DHTMLFunction += " if (((firstDay+x) % 7) == 0)\n";
DHTMLFunction += " {\n";
DHTMLFunction += " calText = calText + </tr><tr>;\n";
DHTMLFunction += " }\n";
DHTMLFunction += " }\n";
DHTMLFunction += " calText = calText + </tr>;";
DHTMLFunction += " calText = calText + </table></td></tr></table>;";
DHTMLFunction += " var CalendarSpan = document.all(calname);";
DHTMLFunction += " if (CalendarSpan != null)";
DHTMLFunction += " CalendarSpan.innerHTML = calText;";
DHTMLFunction += " var CalendarValue = document.all(calname + _CurrentDate);";
DHTMLFunction += " if (CalendarValue != null)";
DHTMLFunction += " CalendarValue.value = + (CurrentDate.getMonth() + 1) + / + CurrentDate.getDate() + / + CurrentDate.getFullYear();";
DHTMLFunction += " } \n";
DHTMLFunction += "</script>\n";

if (Page.Request.UserAgent.IndexOf("MSIE 5.5") != -1)
Page.RegisterClientScriptBlock("ACME_CALENDAR_DHTML", DHTMLFunction);
}

protected void RenderDownLevel(HtmlTextWriter output)
{
// Output Calendar Header

output.WriteLine("<table bgcolor=" + backColor + " border=0 height=190 valign=top><tr><td>");
output.WriteLine("<table bgcolor=" + backColor + " border=0 height=190 valign=top>");
output.WriteLine("<tr><td>");
output.WriteLine("<center>");
output.WriteLine(" <a href=\"javascript:" + Page.GetPostBackEventReference(this, "NavPrevMonth") + "\">");
output.WriteLine("<img src=/quickstart/aspplus/images/left4.gif width=11 height=11 border=0></a>");
output.WriteLine(" <b>" + monthNames[currentDate.Month-1] + " " + Int32.Format(currentDate.Year, null) + "</b>");
output.WriteLine(" <a href=\"javascript:" + Page.GetPostBackEventReference(this, "NavNextMonth") + "\">");
output.WriteLine("<IMG SRC=/quickstart/aspplus/images/right4.gif width=11 height=11 border=0></a>");
output.WriteLine("</center>");
output.WriteLine("</td></tr>");
output.WriteLine("<tr valign=top><td valign=top>");
output.WriteLine("<table border=1 bgcolor=" + foreColor + " height=160>");
output.WriteLine("<tr height=20>");
output.WriteLine(" <td align=right width=23> Sun </td>");
output.WriteLine(" <td align=right width=23> Mon </td>");
output.WriteLine(" <td align=right width=23> Tue </td>");
output.WriteLine(" <td align=right width=23> Wed </td>");
output.WriteLine(" <td align=right width=23> Thu </td>");
output.WriteLine(" <td align=right width=23> Fri </td>");
output.WriteLine(" <td align=right width=23> Sat </td>");
output.WriteLine("</tr>");
output.WriteLine("<tr>");

// Calculate how many days are in the month

int numDays = DateTime.DaysInMonth(currentDate.Year, currentDate.Month);

// Calculate what day of week the first day of the month is on

int firstDay = new DateTime(currentDate.Year, currentDate.Month, 1).DayOfWeek;

// Pre-Day Padding

for (int x=0; x<firstDay; x++)
{
output.WriteLine("<td align=right width=23></td>");
}

// Output each day

for (int x=1; x<=numDays; x++)
{
if (currentDate.Day == x)
{
output.Write("<td align=right width=23>");
output.Write("<font color=red><b><u>" + Int32.Format(x, null) + "</u></b></font>");
output.WriteLine("</td>");
}
else
{
output.Write("<td align=right width=23>");
output.Write("<a href=\"javascript:" + Page.GetPostBackEventReference(this, Int32.Format(x, null)) + "\">");
output.Write(Int32.Format(x, null) + "</a>");
output.WriteLine("</td>");
}

// PerPage row break as appropriate
if (((firstDay+x) % 7) == 0)
{
output.WriteLine("</tr><tr>");
}
}

output.WriteLine("</tr>");
output.WriteLine("</table></td></tr></table></table>");
}

public DateTime Date
{
get
{
return currentDate;
}
set
{
currentDate = value;
}
}

public String BackColor
{
get
{
return backColor;
}
set
{
backColor = value;
}
}

public String ForeColor
{
get
{
return foreColor;
}
set
{
foreColor = value;
}
}

// Todo: We should eliminate the need for a control developer to do stub
// implementations of the below standard IPostDataHandler Methods

public bool LoadPostData(String postDataKey, NameValueCollection values)
{
String clientDate = values[UniqueID + "_CurrentDate"];

if (clientDate != null)
currentDate = DateTime.Parse(clientDate);

return false;
}

public void RaisePostDataChangedEvent()
{

}
}
}

生成服务器控件的文件

csc /t:library /r:System.Web.dll /r:System.dll /out:..\..\..\bin\Acme.dll Acme.cs
csc /t:library /out:..\..\..\bin\WebMarket.dll WebMarket.cs

这个例子的演示在
http://tutorial.superexpert.com/quickstart/aspplus/samples/webforms/intro/intro7.aspx
这个日历的服务器控件可以同时支持高级和低级的浏览器，对于高级的浏览器，他在客户端生成DHTML 代码，DHTML 文档不需要和服务器进行交互！对于低级的浏览器，则生成标准的 HTML 3.2 的代码，这个时候需要和服务器的交互来处理浏览器客户端的用户操作
注意：这个页面的代码的开发者在书写的过程中，开发者不需要关心客户浏览器是高级的还是低级的。日历控件自己会处理两种浏览器之间的差别
下一讲，我们将要进入asp+ 操作 数据库 的章节，请大家随时留意我们的站点更新！

赞(0)
版权申明：本站文章部分自网络，如有侵权，请联系：west999com@outlook.com 特别注意：本站所有转载文章言论不代表本站观点！ 本站所提供的图片等素材，版权归原作者所有，如需使用，请与原作者联系。未经允许不得转载：IDC资讯中心 » asp+语法教程(五)asp+的服务器端编程控件篇_asp教程
分享到： 更多 (0)

相关推荐

热门标签

ldquo (1370)win (1324)活动 (1166)ios (1162)rdquo (818)微信 (747)iphone (728)小米 (722)windows (706)手机 (698)酷跑 (686)飞车 (540)天天 (492)qq (491)网站 (457)全民 (442)discuz (408)充值 (389)安装 (368)更新 (321)华为 (300)浏览器 (292)支付宝 (289)三星 (266)note (264)教程 (262)预览版 (261)小编 (258)越狱 (254)linux (248)

热门文章

分类目录