vb程序

4、实现当前时间的12小时制和24小时制的转换Public Class Form1Dim dt As DateTime = DateTime.NowDim h As Byte = dt.HourDim m As Byte = dt.MinuteDim s As Byte = dt.SecondDim h1 As ByteDim b As BooleanPrivate Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.ClickIf h > 12 Thenh1 = h - 12 : b = FalseEnd IfLabel1.Text = dt.Year & "年" & dt.Month & "月" & dt.Day & "日" & vbCrLfLabel1.Text &= dt.DayOfWeek.ToStringEnd SubPrivate Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.TickTimer1.Interval = 1000s = s + 1If s = 60 Thens = 0 : m = m + 1End IfIf m = 60 Thenm = 0 : h1 = h + 1End IfTextBox1.Text = String.Format("{0:d2}", h1)TextBox2.Text = String.Format("{0:d2}", m)TextBox3.Text = String.Format("{0:d2}", s)End SubPrivate Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.ClickTimer1.Start()End SubPrivate Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.ClickTimer1.Stop()End SubPrivate Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) HandlesButton4.ClickIf b = False Thenh1 = h : b = TrueEnd IfEnd SubPrivate Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.LoadButton1.Text = "12小时制"Button4.Text = "24小时制"End SubEnd Class5、实现任意位数数字的反转：Public Class Form1Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.ClickDim i As Long = Val(TextBox1.Text)Dim str1 As String = ""Dim n As Byte = i.ToString.LengthDim b As ByteFor j = 1 To nb = (i Mod 10 ^ j) \ 10 ^ (j - 1)str1 &= b.ToStringNextTextBox2.Text = str1End SubPrivate Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.LoadLabel1.Text = "请输入任意正整数"Label2.Text = "反过来后组成的整数"End SubEnd Class6、实现任意字符串转：Public Class Form1Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.ClickDim str1 As String = TextBox1.TextDim str2 As String = ""Dim len As Short = str1.LengthDim cha1 As CharFor i = len To 1 Step -1cha1 = Mid(str1, i, 1)str2 &= cha1NextTextBox2.Text = str2End SubPrivate Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.LoadLabel1.Text = "请输入任意字符串"Label2.Text = "反过来后组成的字符串"End SubEnd Class7、实现字母字符的大小写输出：Public Class Form1Private Sub TextBox1_KeyPress(ByVal sender As Object, ByVal e AsSystem.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPressDim cha1 As Char = e.KeyCharIf Char.IsLetter(cha1) ThenTextBox2.Text &= Char.ToLower(cha1) : TextBox3.Text &= Char.ToUpper(cha1) ElseLabel1.Text = "所输入字符中含有非字母的类型！请重输入" : TextBox1.Text = ""End IfEnd SubPrivate Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.LoadTextBox1.Focus()End SubEnd Class6、将标签上的文字一个一个地出现，间隔半秒，循环Public Class Form1Dim str1 As String = "程序设计"Dim len As Byte = str1.LengthDim a() As Char = New Char(9) {}Dim j As Byte = 0Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Loada = str1.ToCharArrayLabel1.Text = ""Label1.Font = New Font("隶书", 30)Label1.ForeColor = Color.BlueTimer1.Interval = 500Me.Size = New Size(400, 300)End SubPrivate Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.ClickTimer1.Start()End SubPrivate Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.TickIf j > 9 Thenj = 0 : Label1.Text = ""End IfLabel1.Text &= a(j)j += 1End SubEnd Class7、将随机数组中最大值求出并闪烁文本框：Public Class Form1Dim j As Int32Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.LoadMe.Controls.Item(0).Text = ""Me.Controls.Item(1).Text = ""Me.Controls.Item(2).Text = ""Me.Controls.Item(3).Text = ""Me.Controls.Item(4).Text = ""Me.Controls.Item(5).Text = ""Me.Controls.Item(6).Text = ""Me.Controls.Item(7).Text = ""Me.Controls.Item(8).Text = ""Me.Controls.Item(9).Text = ""Me.Controls.Item(10).Text = ""End SubPrivate Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.ClickDim ran As New RandomDim temp, i As Int32Dim a() As Int32 = New Int32(10) {}For i = 1 To 10a(i) = ran.Next(100)Controls.Item(i).Text = a(i).ToStringNexttemp = a(1)For i = 1 To 10If temp <= a(i) Thentemp = a(i) : j = iEnd IfNextTimer1.Start()Timer1.Interval = 1000End SubPrivate Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.TickStatic n As Int32n = n + 1If n Mod 2 <> 0 ThenControls.Item(j).BackColor = Color.RedEnd IfIf n Mod 2 = 0 ThenControls.Item(j).BackColor = Color.WhiteEnd IfEnd SubEnd Class。