vb.net GDI+

當(dāng)然是全部重畫。

在壽光等地區(qū)，都構(gòu)建了全面的區(qū)域性戰(zhàn)略布局，加強(qiáng)發(fā)展的系統(tǒng)性、市場前瞻性、產(chǎn)品創(chuàng)新能力，以專注、極致的服務(wù)理念，為客戶提供做網(wǎng)站、成都網(wǎng)站設(shè)計(jì) 網(wǎng)站設(shè)計(jì)制作按需定制,公司網(wǎng)站建設(shè),企業(yè)網(wǎng)站建設(shè),品牌網(wǎng)站設(shè)計(jì),營銷型網(wǎng)站,外貿(mào)網(wǎng)站建設(shè),壽光網(wǎng)站建設(shè)費(fèi)用合理。

層只不過是制圖軟件弄出來的一個(gè)方便的東西而已。

就像你畫畫，畫上去如果你要擦掉當(dāng)然是擦到底色咯。（當(dāng)然GDI+也可以像你畫畫一樣只擦一部分）

GDI+時(shí)鐘我寫過一個(gè)VB6的。代碼詳見我博客。地址顯然百度不讓貼上= =。所以你可以看下我的資料。

你可以模擬層，就是把所有繪制信息都保存起來。你的流程應(yīng)當(dāng)是：

如果要繪制了，更新繪制信息（可以是數(shù)組啥的。），交給一個(gè)Draw過程

Draw過程：根據(jù)繪制信息，全部繪制。

By vIstaswx ,before junior school graduation exam.

vb.net開發(fā)簡單的時(shí)鐘程序？？高手救救我！

就

是

這

個(gè)

了

！

Hand類的代碼：

Public MustInherit Class Hand

Protected gp As GraphicsPath = New GraphicsPath()

Protected gpBase As GraphicsPath = Nothing

Protected midX As Integer = 150 ‘默認(rèn)的窗體

Protected midY As Integer = 150 ‘中心位置

‘構(gòu)造器，得到窗體中心位置

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)

‘繪制指針路徑

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

‘使用矩陣實(shí)現(xiàn)路徑（gp）的旋轉(zhuǎn)

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

為了節(jié)省篇幅，上面的代碼省略了引入命名空間的語句。

下面是分針（MinuteHand）類的定義：

Public Class MinuteHand

Inherits Hand

‘構(gòu)造器，生成繪制分針的路徑（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方法取得系統(tǒng)當(dāng)前時(shí)間，并旋轉(zhuǎn)時(shí)鐘指針。

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

對(duì)所有的指針旋轉(zhuǎn)的方法都是相同的，因此在基類中實(shí)現(xiàn)。由于時(shí)針和秒針的實(shí)現(xiàn)與分針相似，所不同者，只在于構(gòu)造器中繪制的指針路徑不同和Transform方法中轉(zhuǎn)動(dòng)的角度不同，在這里就不在贅述了。

另外還需要提一下的是畫時(shí)鐘表面的代碼，時(shí)鐘表面用ClockFace類來實(shí)現(xiàn)。這個(gè)類首先畫一個(gè)圓代表時(shí)鐘，然后畫上米老鼠的圖案，最后在相應(yīng)的位置畫上數(shù)字1～12代表12個(gè)小時(shí)。

Public Sub Draw(ByVal g As Graphics)

DrawClockFace(g)

DrawImage(g)

DrawNumbers(g)

DrawPin(g)

End Sub

下面是ClockFace類的屬性：

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方法用來畫時(shí)鐘表面：

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對(duì)象的DrawImage方法畫出米老鼠的圖片：

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

數(shù)字在時(shí)鐘上的位置是用sin和cos函數(shù)計(jì)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

最后是窗體文件（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

‘在窗體的OnPaint事件中取得Graphics對(duì)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

‘計(jì)時(shí)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()

怎樣用vb.net作一個(gè)指針轉(zhuǎn)動(dòng)的鐘表?(可設(shè)置時(shí)間日期,有鬧鈴功能)

你需要會(huì)用GDI+,也就是那個(gè)System.Drawing命名空間下的類.

給你說個(gè)思路,設(shè)Timer,到時(shí)間就用Form.Invalidate()函數(shù)重畫窗口,在重畫窗口的Form_Paint事件下面編寫代碼得到當(dāng)前時(shí)間,再根據(jù)當(dāng)前時(shí)間用GDI+畫時(shí)鐘.