可以，创作您自己的 ASP.NET 服务器控件很容易。创建简单的自定义控件时，您所要做的只是定义从 System.Web.UI.Control 派生的类并重写它的 Render 方法。Render 方法采用 System.Web.UI.HtmlTextWriter 类型的参数。控件要发送到客户端的 HTML 作为字符串参数传递到 HtmlTextWriter 的 Write 方法。
例如：
服务器控件代码(简单显示字符串)：
| Simple.vb：
Imports System Imports System.Web Imports System.Web.UI Namespace SimpleControlSamples Public Class SimpleVB : Inherits Control Protected Overrides Sub Render(Output As HtmlTextWriter) Output.Write("< H2>欢迎使用控件开发!< /H2>") End Sub End Class End Namespace 引用文件Simple.aspx： < %@ Register TagPrefix="SimpleControlSamples" Namespace="SimpleControlSamples" Assembly="SimpleControlSamplesVB" %> < html> < body> < form method="POST" action="Simple.aspx" runat=server> < SimpleControlSamples:SimpleVB id="MyControl" runat=server/> < /form> < /body> < /html> |
在ASP.NET程序中发送邮件不再象ASP中那样需要组件的支持了，在.NET的框架基类的System.Web.Mail名称空间内包含的MailMessage和SmtpMail类可以实现这个功能。
例如：
| Dim message As
new Mail.MailMessage
message.From = "web3@163.com" message.To = "web3@163.com" message.Subject = "测试" message.Body = "内容" Mail.SmtpMail.SmtpServer = "localhost" Mail.SmtpMail.Send(message) |
下面举一个从Microsoft SQL Server的PUB数据库读取图片并显示它的例子：
|
< %@ Import Namespace="System.Data.SqlClient"
%>
< %@ Import Namespace="System.Drawing" %> < %@ Import Namespace="System.Drawing.Imaging" %> < %@ Import Namespace="System.IO" %> < script language="VB" runat="server"> Sub Page_load(Sender as Object, E as EventArgs) dim stream as new MemoryStream dim connection as SqlConnection connection=new SqlConnection("server=localhost;database=pubs;uid=sa;pwd=") try connection.Open() dim command as SqlCommand command = new SqlCommand ("select logo from pub_info where pub_id='0736'", connection) dim image as byte() image = command.ExecuteScalar () stream.Write (image, 0, image.Length) dim imgbitmap as bitmap imgbitmap = new Bitmap (stream) Response.ContentType = "image/gif" imgbitmap.Save (Response.OutputStream, ImageFormat.Gif) Finally connection.Close() stream.Clse() End Try End Sub < /script> |