form1.vb

关于简单入门编程资源

Imports System.Text
Imports System.Net
Imports System.Net.Sockets
Imports System.Threading
Imports System.Windows.Forms
Public Class Form1

#Region "学习messagebox类"
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        If TextBox1.Text = "" Then
            MessageBox.Show("You must enter a name.", "Name Entry Error", MessageBoxButtons.AbortRetryIgnore, MessageBoxIcon.Exclamation)
        End If
    End Sub
#End Region

#Region "学习listbox类"
    Private sum As Decimal
    Dim temp1, temp2 As String
    Dim price As Decimal

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        temp1 = ListBox1.SelectedItem
        temp2 = temp1.Substring(5)
        price = Conversion.Val(temp2)
        If sum + price <= Conversion.Val(TextBox2.Text) Then
            sum += price
            ListBox2.Items.Add(temp1)
            TextBox3.Text = sum.ToString
            TextBox4.Text = (Conversion.Val(TextBox2.Text) - sum).ToString
        Else
            MessageBox.Show("你的资金不够", "提示")
        End If
    End Sub

    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
        temp1 = ListBox2.SelectedItem
        temp2 = temp1.Substring(5)
        price = Conversion.Val(temp2)
        sum -= price
        TextBox3.Text = sum
        TextBox4.Text = Conversion.Val(TextBox2.Text) - sum
        ListBox2.Items.Remove(ListBox2.SelectedItem)
    End Sub
#End Region

#Region "乘法口诀"
    Private Sub Button14_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button14.Click
        If TextBox1.Text = "" Then
            MessageBox.Show("You must enter a name.", "Name Entry Error", MessageBoxButtons.AbortRetryIgnore, MessageBoxIcon.Exclamation)
        End If
        Dim i, j As Integer
        Try
            For i = 1 To 9
                For j = 1 To 9
                    TextBox1.AppendText(Str(j) + "*" + Str(i) + "=" + Str(i * j))
                    If i * j > 9 Then
                        TextBox1.AppendText(Space(1))
                    Else
                        TextBox1.AppendText(Space(2))
                    End If
                Next j
                TextBox1.AppendText(vbLf)
            Next i
        Catch ex As Exception

        End Try

        '        Dim s As String = "71151280 gd 25.5 5 3 no"
        '        Dim c() As String
        '        c = s.Split(" ")Public Function Split(ByVal ParamArray separator() As Char) As String()
        '成员属于:   System.String()
        '摘要:
        '返回包含此实例中的子字符串（由指定 System.Char 数组的元素分隔）的 System.String 数组。

        '参数:
        'separator: 分隔此实例中子字符串的 Unicode 字符数组、不包含分隔符的空数组或null。 

        '返回值:
        '一个数组，其元素包含此实例中的子字符串，这些子字符串由 separator 中的一个或多个字符分隔。有关更多信息，请参见备注部分。

    End Sub
#End Region

#Region "数组转置"
    Private Sub Button8_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button8.Click
        Dim t1 As String = Nothing
        Dim t2 As String = Nothing
        Dim a, b As Integer
        Dim arr(3, 4), tarr(4, 3) As Integer
        For a = 0 To 3
            For b = 0 To 4
                arr(a, b) = a + b
                t1 = t1 + Str(arr(a, b))
            Next b
            t1 = t1 + vbCr
        Next a
        For a = 0 To 4
            For b = 0 To 3
                tarr(a, b) = arr(b, a)
                t2 += Str(tarr(a, b))

            Next b
            t2 += vbCr
        Next a
        MessageBox.Show(t1 + "  " + vbCr + t2)
    End Sub
#End Region

#Region "查询数据"
    Private Sub Button9_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button9.Click
        Dim a(5, 5) As Integer
        Dim i1, j1, k, flag As Integer
        Label1.Text = "数组为：" & vbNewLine
        For i1 = 1 To 5
            For j1 = 1 To 5
                a(i1, j1) = Int(Rnd() * 10) + 5
                Label1.Text &= " " & a(i1, j1)
            Next j1
            Label1.Text &= vbNewLine
        Next i1
        flag = 0
        For Each k In a
            If k = Convert.ToInt32(TextBox5.Text) Then
                flag = 1
                Exit For
            End If
        Next
        If flag = 1 Then
            MessageBox.Show("在数组中")
        Else
            MessageBox.Show("不在数组中")
        End If
    End Sub
#End Region

#Region "从数组中选择位置删除数据"
    Private Sub Button10_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button10.Click
        Dim b(5) As Integer
        Dim i2, j2 As Integer
        Label3.Text = "删除前数组为：" & vbNewLine
        For i2 = 0 To 5
            b(i2) = Int(Rnd() * 20) + 5
            Label3.Text &= " " & b(i2)
        Next i2
        j2 = Conversion.Int(TextBox6.Text)
        For i2 = j2 To 4
            b(i2) = b(i2 + 1)
        Next
        ReDim Preserve b(4)
        Label4.Text = "删除后的数组为：" & vbNewLine
        For i2 = 0 To 4
            Label4.Text &= " " & b(i2)
        Next i2
    End Sub
#End Region

#Region "function 函数调用"

    Private Sub Button11_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button11.Click
        Dim n As Integer
        n = Val(TextBox7.Text)
        TextBox8.Text = y(n)
        '定义函数y(n)
    End Sub

    '定义函数
    Function y(ByVal m As Integer)
        Dim i3 As Integer
        Dim s As Integer
        For i3 = 1 To m
            s = i3 ^ 2
        Next i3
        Return s
    End Function
#End Region

#Region "PLC通信"

    Private mip As IPAddress = IPAddress.Parse("192.168.0.218")
    Private mport As Integer = 2000
    Private mTcplisten As TcpListener = Nothing
    Private mtcpcli As TcpClient = Nothing
    Private mStream As NetworkStream = Nothing
    Private mTerminate As Boolean = False
    Private mReadthread As Thread
    Private mWritethread As Thread
    Private mRunning As Boolean = False  ' 是否在运行

    '定义IP地址属性
    Public Property IP() As IPAddress
        Get
            Return mip
        End Get
        Set(ByVal value As IPAddress)
            Me.mip = value
        End Set
    End Property

    '定义端口属性
    Public Property port() As Integer
        Get
            Return mport
        End Get
        Set(ByVal value As Integer)
            Me.mport = value
        End Set
    End Property

    '开始连接
    Private Sub Button12_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button12.Click
        Me.tryconnect()
    End Sub

    '启动连接
    Private Sub tryconnect()
        If mTcplisten Is Nothing Then
            mTcplisten = New TcpListener(mip, mport)
        End If
        Try
            mTcplisten.Start()
            mtcpcli = mTcplisten.AcceptTcpClient
            mStream = mtcpcli.GetStream

            '启动写线程
            mTerminate = False
            mWritethread = Nothing
            mWritethread = New Thread(AddressOf Me.Writethread)
            mWritethread.Start()

            '启动读线程
            mTerminate = False
            mReadthread = Nothing
            mReadthread = New Thread(AddressOf Me.Readthread)
            mReadthread.Start()

        Catch ex As Exception
            MessageBox.Show("不能连接到PLC")
        End Try
    End Sub

    '读线程
    Private Sub Readthread()
        Dim buf(1024) As Byte
        Try
            Dim len As Integer = 6