16,554
社区成员
发帖
与我相关
我的任务
分享picturebox的autoredraw问题
在网上搜索了一下在.net中的picturebox可以用下面的代码做到，我想用多个线程来操作picturebox，发现如果不用timer中的PictureBox1.Image = bgimage 来不断刷新就实现不了。如何让picturebox能真正的实现自动刷新？而不用手动的来刷新？
Public Class Form1
Dim g2 As Graphics
Dim xp1 As Bitmap = My.Resources.sanjiao
Dim bgimage As Bitmap
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
bgimage = New Bitmap(PictureBox1.Width, PictureBox1.Height) '创建相同大小的内存位图
g2 = Graphics.FromImage(bgimage)
PictureBox1.Image = bgimage
g2.DrawImage(My.Resources.tr, 0, 0)
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim t1 As New Thread(AddressOf thread1)
t1.Start()
End Sub
Private Sub thread1()
For a As Integer = 1 To 10000000
g2.DrawImage(xp1, 20, 20)
Thread.Sleep(1)
Next
End Sub
Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
PictureBox1.Image = bgimage
End Sub
End Class
Public Class Form1
Dim g2 As Graphics
Dim xp1 As Bitmap = My.Resources.sanjiao
Dim bgimage As Bitmap
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
bgimage = New Bitmap(PictureBox1.Width, PictureBox1.Height) '创建相同大小的内存位图
g2 = Graphics.FromImage(bgimage)
PictureBox1.Image = bgimage
g2.DrawImage(My.Resources.tr, 0, 0)
End Sub
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim t1 As New Thread(AddressOf thread1)
t1.Start()
End Sub
Private Sub thread1()
For a As Integer = 1 To 10000000
g2.DrawImage(xp1, 20, 20)
Thread.Sleep(1)
Next
End Sub
Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
PictureBox1.Image = bgimage
End Sub
End Class
...全文
请发表友善的回复…
发表回复
dylike 2011-08-05
- 打赏
- 举报
没有看懂.说说你想实现什么?
timezone 2011-02-18
- 打赏
- 举报
还有没有高手指点一下啊
timezone 2011-02-17
- 打赏
- 举报
[Quote=引用 3 楼 xingyuebuyu 的回复:]
VB.NET code
Public Class Form1
Dim g2 As Graphics
Dim xp1 As Bitmap = My.Resources.sanjiao
Dim bgimage As Bitmap
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e ……
[/Quote]
感谢楼上的高手的回答，如果我在线程中有许多drawimage和drawstring的操作，而且在线程里的图像操作是变化的，那就不可能全部放到onpain中吧。现在我用线程来绘图这些没有问题，问题是因为要用到timer来PictureBox1.Image = bgimage
不断刷新实现绘制的内容反应到Picturebox上而占用太高的cpu，请问有没有什么办法能实时的更新到picturebox上
VB.NET code
Public Class Form1
Dim g2 As Graphics
Dim xp1 As Bitmap = My.Resources.sanjiao
Dim bgimage As Bitmap
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e ……
[/Quote]
感谢楼上的高手的回答，如果我在线程中有许多drawimage和drawstring的操作，而且在线程里的图像操作是变化的，那就不可能全部放到onpain中吧。现在我用线程来绘图这些没有问题，问题是因为要用到timer来PictureBox1.Image = bgimage
不断刷新实现绘制的内容反应到Picturebox上而占用太高的cpu，请问有没有什么办法能实时的更新到picturebox上
xingyuebuyu 2011-02-17
- 打赏
- 举报
Public Class Form1
Dim g2 As Graphics
Dim xp1 As Bitmap = My.Resources.sanjiao
Dim bgimage As Bitmap
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
bgimage = New Bitmap(PictureBox1.Width, PictureBox1.Height) '创建相同大小的内存位图
g2 = Graphics.FromImage(bgimage)
PictureBox1.Image = bgimage
End Sub
Private Sub PictureBox1_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles PictureBox1.Paint
If g2 IsNot Nothing AndAlso xp1 IsNot Nothing Then
g2.DrawImage(My.Resources.tr, 0, 0)
g2.DrawImage(xp1, 20, 20)
End If
End Sub
End Class
绘图放在Paint事件中就会自动刷新的
timezone 2011-02-17
- 打赏
- 举报
楼上的这位大侠回复的是什么意思啊？用invalidate吗？
wuyq11 2011-02-17
- 打赏
- 举报
Invalidate作用是重新执行paint以更新失效区域
using (bitmap B = new bitmap(picturebox1.width, picturebox1.height)) {
using (graphics G = graphics.fromimage(B)) {
point P = new point(3, 3);
point q = new point(5, 5);
pen pen = new pen(color.blue, 3);
G.DrawLinde(pen, P, q);
}
picturebox1.Image = B;
}
using (bitmap B = new bitmap(picturebox1.width, picturebox1.height)) {
using (graphics G = graphics.fromimage(B)) {
point P = new point(3, 3);
point q = new point(5, 5);
pen pen = new pen(color.blue, 3);
G.DrawLinde(pen, P, q);
}
picturebox1.Image = B;
}
