测试网络连接的自定义ping类

闲话少述，直接代码，然后给出一个示范;

Imports System
Imports System.Net
Imports System.Net.Sockets
Imports System.Net.NetworkInformation
Imports System.Threading
Imports System.IO
Imports System.Text

'创建一个ping类，flag返回ping的结果

Public Class myping
    Public ipstr As String
    Public flag As Boolean = False
    Public NoexitPing As Boolean = True
    Public ThreadPing As Thread
    Public waiteTime As Integer = 100
    Public JoinFlag As Boolean = True
    Public Sub New()
        'SyncLock GetType(myping)
        If NoexitPing = True Then
            Try
                ThreadPing = New Thread(AddressOf pingSingle)
                ThreadPing.Priority = ThreadPriority.BelowNormal
            Catch ex As Exception

            End Try
        End If
        'End SyncLock
    End Sub
    Public Sub pingStart()
        'SyncLock GetType(myping)
        If NoexitPing = True Then
            ThreadPing.Start()
            If JoinFlag Then
                ThreadPing.Join()
            Else
                Dim n As Integer = 0
                Do While n < waiteTime And flag = False
                    n += 10
                    Thread.Sleep(10)
                Loop
            End If

        Else
            ThreadPing.Abort()
        End If
        'End SyncLock
    End Sub
    Public Sub pingAbort()
        NoexitPing = False
        Try
            ThreadPing.Abort()
        Catch ex As Exception

        End Try
    End Sub
    Public Sub pingSingle() '指向ipstr的ping函数
        If NoexitPing = False Then Exit Sub
        Try
            flag = My.Computer.Network.Ping(ipstr)
        Catch ex As Exception
            flag = False
        End Try
    End Sub
End Class

 

应用示范：测试192.168.0网段内所有机器

三个文本框，填上192 168 0，一个按钮执行搜索，一个listbox1显示搜索内容。

创建线程t，线程内调用委托

    Private t As Thread
    Private Delegate Sub 消息()
    Private pingStr As String
    Private myp As myping
    Private num As Integer
    Private Sub 显示结果()
        Me.ListBox1.Items.Add(pingStr)
        Me.ProgressBar1.Value = num
    End Sub
    Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
        Me.ListBox1.Items.Clear()
        Me.ProgressBar1.Visible = True
        Me.ProgressBar1.Maximum = 255
        t = New Thread(AddressOf myping) '建立新的线程
        t.Start()  '启动线程
    End Sub

 

'///////////////////myping是主程序

 

    Private Sub myping()
        Dim a As Integer = CInt(TextBox1.Text), b As Integer = CInt(TextBox2.Text), c As Integer = TextBox3.Text
        Dim i As Integer
        For i = 1 To 255
            Try
                myp = New myping
                myp.ipstr = a.ToString & "." & b.ToString & "." & c.ToString & "." & i
                myp.JoinFlag = False '默认是TRUE，等待线程结束，时间比较长
                myp.pingStart()

                pingStr = myp.ipstr & "..." & myp.flag.ToString   '检测网络连通的方法
                num = i
                myp.pingAbort()

                Dim dh As 消息 = New 消息(AddressOf 显示结果)
                If Me.InvokeRequired = True Then Me.Invoke(dh)
                dh = Nothing

            Catch ex As Exception
                MsgBox(ex.ToString)
            End Try
        Next
        t.Abort()

    End Sub