求一个VB.NET进行局域网内UDP广播的源代码例子

给你个udp多播例子，广播不是很清楚，呵呵

创新互联建站-专业网站定制、快速模板网站建设、高性价比和静网站开发、企业建站全套包干低至880元,成熟完善的模板库,直接使用。一站式和静网站制作公司更省心,省钱,快速模板网站建设找我们，业务覆盖和静地区。费用合理售后完善，十载实体公司更值得信赖。

Imports System.Net

Imports System.Net.Sockets

Imports System.Text

Public Class Form1

Inherits System.Windows.Forms.Form

Dim port As String

Dim ipadd As String

Dim ipend As IPEndPoint

Dim sendudp As New UdpClient()

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _

Handles Button1.Click

Dim ipadress As IPAddress

ipadress = IPAddress.Parse(TextBox1.Text)

'sendport = Int32.Parse(TextBox2.Text)

'ipend = New IPEndPoint(ipadress, sendport)

Try

sendudp.JoinMulticastGroup(ipadress)

MessageBox.Show("启动完成！")

Catch ex As Exception

MessageBox.Show(ex.Message)

End Try

End Sub

哪位大哥给我一个VB.NET打印的例子

PrintDocument1.Print()

使用PrintDocument进行打印“Brush, 50, 80”50左边距离，80上面距离

Private Sub PrintDocument1_PrintPage(sender As Object, e As Printing.PrintPageEventArgs) Handles PrintDocument1.PrintPage

Dim mypen As Pen = New Pen(Color.Blue, 2)

e.Graphics.DrawString("取号单", New Font("Microsoft Sans Serif", 18, FontStyle.Bold), New Pen(Color.Black, 1).Brush, 30, 30)

e.Graphics.DrawString("XXXXXX", New Font("Microsoft Sans Serif", 24, FontStyle.Regular), New Pen(Color.Black, 1).Brush, 50, 80)

e.Graphics.DrawString("您的号码是：", New Font("Microsoft Sans Serif", 16, FontStyle.Regular), New Pen(Color.Black, 1).Brush, 30, 135)

e.Graphics.DrawString("打印时间:" Now(), New Font("Microsoft Sans Serif", 10, FontStyle.Regular), New Pen(Color.Black, 1).Brush, 80, 330)

End Sub

vb.net怎么用构造函数传参进行窗体间跳转？

Public Class Form2

Dim test As String

Public Sub New(ByVal _test As String)

test = _test

End Sub

End Class

Form1 中 New Form2("abc") 即可传参给 Form2 中的 test。

但在 VB.NET 中，没必要这么麻烦，只需要声明为 Public，即可直接方法，如：

Public Class Form2

Public test As String

End Class

Form1 中直接 Form2.test = "abc" 即可。

vb.net开发简单的时钟程序？？高手救救我！

就

是

这

个

了

！

Hand类的代码：

Public MustInherit Class Hand

Protected gp As GraphicsPath = New GraphicsPath()

Protected gpBase As GraphicsPath = Nothing

Protected midX As Integer = 150 ‘默认的窗体

Protected midY As Integer = 150 ‘中心位置

‘构造器，得到窗体中心位置

Public Sub New(ByVal theForm As Form1)

midX = (theForm.ClientRectangle.Left + theForm.ClientRectangle.Right) / 2

midY = (theForm.ClientRectangle.Top + theForm.ClientRectangle.Bottom) / 2

End Sub

MustOverride Sub Transform(ByVal d As DateTime)

‘绘制指针路径

Overridable Sub Draw(ByVal g As Graphics)

Dim aPen As Pen = New Pen(Brushes.Black, 4F)

g.DrawPath(aPen, gp)

g.FillPath(Brushes.Black, gp)

aPen.Dispose()

End Sub

‘使用矩阵实现路径（gp）的旋转

Public Sub Rotate(ByVal angle As Double)

gp = CType(gpBase.Clone(), GraphicsPath)

Dim mTransform As Matrix = New Matrix()

mTransform.RotateAt(CType(angle,Single),NewPointF(midX,midY))

gp.Transform(mTransform)

End Sub

End Class

为了节省篇幅，上面的代码省略了引入命名空间的语句。

下面是分针（MinuteHand）类的定义：

Public Class MinuteHand

Inherits Hand

‘构造器，生成绘制分针的路径（gp）

Public Sub New(ByVal myForm As Form1)

MyBase.New(myForm)

gp.AddLine(midX, midY, midX, 45)

gp.AddLine(midX, 45, midX - 3, 50)

gp.AddLine(midX - 3, 50, midX + 3, 50)

gp.AddLine(midX + 3, 50, midX, 45)

gpBase = CType(gp.Clone(), GraphicsPath)

End Sub

‘Transform方法取得系统当前时间，并旋转时钟指针。

Public Overrides Sub Transform(ByVal d As DateTime)

Dim minuteTime As Double = (CDbl(d.Minute) + CDbl(d.Second / 60))

Dim angle As Double = (CDbl(minuteTime) / 60) * 360

Rotate(angle)

End Sub

End Class

对所有的指针旋转的方法都是相同的，因此在基类中实现。由于时针和秒针的实现与分针相似，所不同者，只在于构造器中绘制的指针路径不同和Transform方法中转动的角度不同，在这里就不在赘述了。

另外还需要提一下的是画时钟表面的代码，时钟表面用ClockFace类来实现。这个类首先画一个圆代表时钟，然后画上米老鼠的图案，最后在相应的位置画上数字1～12代表12个小时。

Public Sub Draw(ByVal g As Graphics)

DrawClockFace(g)

DrawImage(g)

DrawNumbers(g)

DrawPin(g)

End Sub

下面是ClockFace类的属性：

Private ClockRectangle As Rectangle

Private ClockFont As Font = New Font("Arial", 12)

Private midPoint As Point

Private ClockImage As Bitmap

Private Const IMAGEX As Integer = 50

Private Const IMAGEY As Integer = 50

DrawClockFace方法用来画时钟表面：

Private Sub DrawClockFace(ByVal g As Graphics)

g.FillEllipse(Brushes.White, ClockRectangle.Left + 10, ClockRectangle.Top + 10, ClockRectangle.Width - 20, ClockRectangle.Height - 20)

g.DrawEllipse(Pens.Black, ClockRectangle.Left + 10, ClockRectangle.Top + 10, ClockRectangle.Width - 20, ClockRectangle.Height - 20)

End Sub

然后用Graphics对象的DrawImage方法画出米老鼠的图片：

Private Sub DrawImage(ByVal g As Graphics)

Dim nWidth As Integer = ClockImage.Width

Dim nHeight As Integer = ClockImage.Height

Dim destRect As Rectangle = New Rectangle(midPoint.X - IMAGEX / 2, midPoint.Y - IMAGEY / 2, IMAGEX, IMAGEY)

g.DrawImage(ClockImage, destRect)

End Sub

数字在时钟上的位置是用sin和cos函数计算的：

Private Sub DrawNumbers(ByVal g As Graphics)

Dim count As Integer = 1

Dim a As Double

For a = 0 To 2 * Math.PI Step 2 * Math.PI / 12

Dim x As Double = (ClockRectangle.Width - 70) / 2 * Math.Cos(a - Math.PI / 3) + (ClockRectangle.Width - 70) / 2 + 25

Dim y As Double = (ClockRectangle.Width - 70) / 2 * Math.Sin(a - Math.PI / 3) + (ClockRectangle.Width - 70) / 2 + 20

g.DrawString(Convert.ToString(count), ClockFont, Brushes.Black, CType(x, Single), CType(y, Single), New StringFormat())

count += 1

Next

End Sub

最后是窗体文件（Form1.vb）:

Public Class Form1

Inherits System.Windows.Forms.Form

Private MyMinuteHand As MinuteHand

Private MyHourHand As HourHand

Private MySecondHand As SecondHand

Private TheClockFace As ClockFace

Private FirstTick As Boolean = False

‘在窗体的OnPaint事件中取得Graphics对象

Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs)

If (FirstTick = False) Then Exit Sub

Dim g As Graphics = e.Graphics

TheClockFace.Draw(g)

MyHourHand.Draw(g)

MyMinuteHand.Draw(g)

MySecondHand.Draw(g)

TheClockFace.DrawPin(g)

End Sub

‘计时器事件

Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick

MySecondHand.Transform(DateTime.Now)

MyHourHand.Transform(DateTime.Now)

MyMinuteHand.Transform(DateTime.Now)

FirstTick = True

Invalidate()

vb.net中如何结束一个线程

vb.net中如何结束一个线程

一般而言,如果您想终止一个线程,您可以使用System.Threading.Thread类的Abort方法. 例如:

Dim worker As ThreadStart = New ThreadStart(AddressOf workerthreadmethod)

Dim t As Thread = New Thread(worker)

t.Start()

MessageBox.Show("Wait for a while for the thread to start.")

MessageBox.Show(t.ThreadState.ToString())

t.Abort()

MessageBox.Show(t.ThreadState.ToString())

t.Join()

MessageBox.Show(t.ThreadState.ToString())

当然,在调用Abort方法后,线程并不是立刻终止,要等线程的所有finally快中的代码完成后才会完全终止. 所以在主线程中可以用Join方法来同步,当线程还未完全终止时,t.Join()将处于等待,直到t线程完全结束后再继续执行后面的语句。

Abort方法是会导致线程跳出一个异常错误的，你需要在代码中捕获该异常。下面是一个比较完整的VB.NET线程例子：

Imports System

Imports System.Threading

Public Class MyTestApp

Public Shared Sub Main()

Dim t As New Thread(New ThreadStart(AddressOf MyThreadMethod))

'Start the thread

t.Start()

MsgBox("Are you ready to kill the thread?")

'Kill the child thread and this will cause the thread raise an exception

t.Abort()

' Wait for the thread to exit

t.Join()

MsgBox("The secondary thread has terminated.")

End Sub

Shared Sub MyThreadMethod()

Dim i As Integer

Try

Do While True

Thread.CurrentThread.Sleep(1000)

Console.WriteLine("This is the secondary thread running.")

Loop

Catch e As ThreadAbortException

MsgBox("This thread is going to be terminated by the Abort method in the Main function")

End Try

End Sub

End Class

Thread.Abort()方法用来永久销毁一个线程，而且将抛出ThreadAbortException异常。使终结的线程可以捕获到异常但是很难控制恢复，仅有的办法是调用Thread.ResetAbort()来取消刚才的调用，而且只有当这个异常是由于被调用线程引起的异常。因此，A线程可以正确的使用Thread.Abort()方法作用于B线程，但是B线程却不能调用Thread.ResetAbort()来取消Thread.Abort()操作。