包含vb.net划图的词条

vb.net怎样在当前已打开的AutoCAD画图? 最好有个判断语句, 如果CAD已打开, 在当前画图; 如果没有, 则打开

Private Function isopen() As AutoCAD.AcadApplication

Try

dim CADapp_temp AutoCAD.AcadApplication = GetObject(, "AutoCAD.Application")

return CADapp_temp

Catch ex As Exception

Return Nothing

End Try

End Function

'调用上面的函数,如果为nothing表示没有打开，否则打开并返回对象

相关问答

Q1: vb.net 画图 如何保持图形

不用PictureBoxTest.Image属性，直接把图形绘制到PictureBoxTest上面就可以了。

Dim button As Integer = 0

Private Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs) _

    Handles Button1.Click

    Using g As Graphics = Graphics.FromHwnd(PictureBoxTest.Handle)

        Dim penRed As Pen = New Pen(Color.Red, 1)     '定义红色画笔  

        Dim penblue As Pen = New Pen(Color.Blue, 1) '定义蓝色画笔 

        If button = 0 Then

            g.DrawLine(penRed, 0, 0, 100, 100)

            button = 1

        ElseIf button = 1 Then

            g.DrawLine(penblue, 100, 100, 200, 200)

            button = 0

        End If

    End Using

End Sub

Q2: VB.net中如何画图？

VB.net与VB不同。

VB.net已经有专门绘图的类。

可以定义笔刷然后用Drawing类中的方法绘制。

Private Sub DrawEllipse()

Dim myPen As New System.Drawing.Pen(System.Drawing.Color.Red)

Dim formGraphics as System.Drawing.Graphics

formGraphics = Me.CreateGraphics()

formGraphics.DrawEllipse(myPen, New Rectangle(0,0,200,300))

myPen.Dispose()

formGraphics.Dispose()

End Sub

Private Sub DrawRectangle()

Dim myPen As New System.Drawing.Pen(System.Drawing.Color.Red)

Dim formGraphics as System.Drawing.Graphics

formGraphics = Me.CreateGraphics()

formGraphics.DrawRectangle(myPen, New Rectangle(0,0,200,300))

myPen.Dispose()

formGraphics.Dispose()

End Sub

Q3: 关于vb.net中绘图并保存图片的问题

Imports System.Drawing.Imaging

Public Class Form1

Dim imageName As String = "C:\Documents and Settings\...\1126.jpg "

Dim i As Image = Image.FromFile(imageName)

Dim g As Graphics = Graphics.FromImage(i) '此处从背景图创建Greaphics

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

'划线

Dim BluePen As New Pen(Color.Blue, 5)

BluePen.DashStyle = Drawing2D.DashStyle.Solid

g.DrawLine(BluePen, 100.0F, 170, 500.0F, 170)

g.Dispose()

PictureBox1.Image = i

End Sub

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click

'退出

Me.Close()

End Sub

Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click

'存盘

i.Save( "C:\testimage.jpg ", ImageFormat.Jpeg)

i.Dispose()

End Sub

Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

PictureBox1.Image = i

End Sub

End Class

Q4: vb.net 画图对象问题

参考一下下面这段代码：

‘ 首先picturebox1 加载一张图像

FolderBrowserDialog1.Description = "选择图片文件夹导入图片"

FolderBrowserDialog1.ShowDialog()

path = FolderBrowserDialog1.SelectedPath()

If path = "" Then Return

strSrcFile = Dir(path  "\*.tif")

PictureBox1.Image = Image.FromFile(path  "\"  strSrcFile)

’  然后再在picturebox1中用graphic画图而不清空原图像

' 建立一个画图对象

Dim g As Graphics = Me.PictureBox1.CreateGraphics

‘ 定义画笔

Dim myPen As System.Drawing.Pen = New System.Drawing.Pen(Color.Blue)

’ 画出矩形框并且填充颜色（颜色保持50%的透明度，使得下面原来的图片背景能看得到）

g.DrawRectangle(myPen, New System.Drawing.Rectangle(50, 50, 30, 20))

g.FillRectangle(New SolidBrush(Color.FromArgb(50, Color.YellowGreen)), New System.Drawing.Rectangle(50, 50, 30, 20))

' 最后释放画图对象

g.Dispose()

效果大致如下图所示：