189 8069 5689
1、vb.net 完全符合面向对象的编程语言抽象、封装、继承的四大特性，而vb不支持继承。
成都创新互联公司-专业网站定制、快速模板网站建设、高性价比天全网站开发、企业建站全套包干低至880元,成熟完善的模板库,直接使用。一站式天全网站制作公司更省心,省钱,快速模板网站建设找我们，业务覆盖天全地区。费用合理售后完善，10年实体公司更值得信赖。
2、错误处理不同。
vb中只是On Error.....goto和On Errer Resume Next ，这些错误称为非结构化异常处理。而在vb.net中采用的结构化异常处理机制，try...catch....finally控制。
3、两者产生的窗体不同。
vb.net 允许创建不同类型的应用程序，例如，创建ASP.NET和ASP.NET Web 服务应用程序，还允许创建控制台应用程序和作为桌面服务运行的应用程序。但是vb 只能创建Windows窗体。
4、数据库访问的差别。
vb6.0是通过ADO（Active X Data Objext）来实现对数据库访问。而vb.net 是通过ADO.NET来访问数据库。
扩展资料
Visual Basic（简称VB）是Microsoft公司开发的一种通用的基于对象的程序设计语言，为结构化的、模块化的、面向对象的、包含协助开发环境的事件驱动为机制的可视化程序设计语言。是一种可用于微软自家产品开发的语言。
“Visual” 指的是开发图形用户界面 (GUI) 的方法——不需编写大量代码去描述界面元素的外观和位置，而只要把预先建立的对象add到屏幕上的一点即可。
“Basic”指的是 BASIC (Beginners All-Purpose Symbolic Instruction Code) 语言，是一种在计算技术发展历史上应用得最为广泛的语言。
Visual Basic源自于BASIC编程语言。VB拥有图形用户界面（GUI）和快速应用程序开发（RAD）系统，可以轻易的使用DAO、RDO、ADO连接数据库，或者轻松的创建Active X控件，用于高效生成类型安全和面向对象的应用程序 。
参考资料：百度百科-Visual Basic
用 vb.net socket通信
Dim th As Threading.Thread
2 Dim tcpl As System.Net.Sockets.TcpListener
3
4 Private Sub Form1_Load()Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
5 th = New System.Threading.Thread(New System.Threading.ThreadStart(AddressOf MyListen))
6 th.Start()
7 End Sub
8
9 Public Sub SendMessage()Sub SendMessage(ByVal IP As String, ByVal SendMsg As String)
10 Try
11 If IP "" Then
12 Dim tcpc As New System.Net.Sockets.TcpClient(IP, 5656)
13 Dim tcpStream As Net.Sockets.NetworkStream = tcpc.GetStream
14 Dim reqStream As New IO.StreamWriter(tcpStream)
15 reqStream.Write(SendMsg)
16 reqStream.Flush()
17 tcpStream.Close()
18 tcpc.Close()
19 End If
20 Catch ex As Exception
21 MsgBox(ex.Message.ToString)
22 End Try
23 End Sub
24 Private Sub MyListen()Sub MyListen()
25 Try
26 Dim ipAddress As System.Net.IPAddress = System.Net.Dns.Resolve(System.Net.Dns.GetHostName).AddressList(0)
27 tcpl = New System.Net.Sockets.TcpListener(ipAddress, 5656)
28 tcpl.Start()
29 While True
30 Dim s As System.Net.Sockets.Socket = tcpl.AcceptSocket()
31 Dim MyBuffer(1024) As Byte
32 Dim i As Integer
33 i = s.Receive(MyBuffer)
34 If i 0 Then
35 Dim lstrRec As String
36 Dim j As Integer
37 For j = 0 To i - 1
38 TextBox1.Text += Chr(MyBuffer(j)) ","
39 Next
40 End If
41 End While
42 Catch ex As Exception
43 MsgBox(ex.Message.ToString)
44 End Try
45 End Sub
46
47 Private Sub Button1_Click()Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
48 SendMessage("192.168.0.61", TextBox2.Text)
49 End Sub
你是指Internet上的国际标准时间吗。
先加入控件 AxWinsock1 在.Com中Microsoft.Winsock
Public Class Form1
Private Declare Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Integer)
Dim NoSrv As Boolean
Dim TimeFromNet As String
Dim OldTime As Date
Dim NewTime As Date
Dim MyDate As Date
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
If AxWinsock1.CtlState MSWinsockLib.StateConstants.sckClosed Then AxWinsock1.Close()
AxWinsock1.Protocol = MSWinsockLib.ProtocolConstants.sckTCPProtocol
NetTime("") '首先取中科院国家授时中心时间
If NoSrv Or TimeFromNet = "" Then
NetTime("time.nist.gov") '取美国标准技时院时间
If NoSrv Or TimeFromNet = "" Then
MsgBox("检测不到网络标准时间服务器time.nist.gov！")
Else
NetTime("time.nist.gov")
If TimeFromNet = "" Then
MsgBox("网络标准时间服务器time.nist.gov超时！")
Else
MyDate = Mid(TimeFromNet, 8, 8)
OldTime = Mid(TimeFromNet, 17, 8)
NewTime = TimeSerial((Hour(OldTime) + 8) Mod 24, Minute(OldTime), Second(OldTime))
Dim MyTime As DateTime = MyDate Space(1) NewTime
MsgBox(MyTime)
'SetWindowsClock(MyTime)
End If
End If
Else
'使网络误差时间小，第2次再中科院国家授时中心时间
NetTime("")
If TimeFromNet = "" Then
MsgBox("网络标准时间服务器超时！")
Else
MyDate = Mid(TimeFromNet, 8, 8)
NewTime = Mid(TimeFromNet, 17, 8)
Dim MyTime As DateTime = MyDate Space(1) NewTime
MsgBox(MyTime)
'SetWindowsClock(MyTime)
End If
End If
End Sub
Private Sub NetTime(ByVal TimeSrv As String)
NoSrv = False
TimeFromNet = ""
If AxWinsock1.CtlState MSWinsockLib.StateConstants.sckClosed Then AxWinsock1.Close()
AxWinsock1.RemoteHost = TimeSrv ' "" 或 "time.nist.gov"
AxWinsock1.RemotePort = 13
AxWinsock1.LocalPort = 0
AxWinsock1.Connect()
Do While TimeFromNet = ""
If NoSrv Then Exit Do
Sleep(55)
System.Windows.Forms.Application.DoEvents()
Loop
If AxWinsock1.CtlState MSWinsockLib.StateConstants.sckClosed Then AxWinsock1.Close()
End Sub
Private Sub AxAxWinsock1_CloseEvent(ByVal sender As Object, ByVal e As System.EventArgs) Handles AxWinsock1.CloseEvent
AxWinsock1.Close()
End Sub
Private Sub AxAxWinsock1_DataArrival(ByVal sender As Object, ByVal e As AxMSWinsockLib.DMSWinsockControlEvents_DataArrivalEvent) Handles AxWinsock1.DataArrival
AxWinsock1.GetData(TimeFromNet)
End Sub
Private Sub AxAxWinsock1_Error(ByVal sender As Object, ByVal e As AxMSWinsockLib.DMSWinsockControlEvents_ErrorEvent) Handles AxWinsock1.Error
NoSrv = True
End Sub
End Class