Question

vb.net picture 保存图片

visual stitdo 2010。vb，在picturexbox中使用graphics drawline画线。想把画好的线保存成图片，如何操作？？？？

Answer 1

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click '好处：画的图刷新不会消失
PictureBox1.Image = Nothing
Dim wid As Integer = PictureBox1.ClientSize.Width
Dim hgt As Integer = PictureBox1.ClientSize.Height
Dim bm As New Bitmap(wid, hgt)
Dim g As Graphics = Graphics.FromImage(bm)
'画图代码，比如下面的直线
g.DrawLine(Pens.Red, 10, 10, 500, 10)

'画图代码
PictureBox1.Image = bm
PictureBox1.Refresh()
g.Dispose()
PictureBox1.Image.Save("C:\1.jpg")
End Sub

追问

如何指定保存文件的名字，就是弹出那个另存为的对话框啊？

追答

Dim fbd As New FolderBrowserDialog
fbd.ShowDialog()
' MsgBox(fbd.SelectedPath) 'fbd.SelectedPath表示选择路径，如果是根目录，会带“\”,如“D:\”,否则末尾不带"\",如：“D:\TDDOWNLOAD”

Answer 2

先要建立bitmap，使它与PictureBox1关联
Dim mybitmap As Bitmap
Dim Graph As Graphics
下面的可以放在new里面
mybitmap = New Bitmap(300, 150)
PictureBox1.Image = mybitmap
Graph = Graphics.FromImage(PictureBox1.Image)

下面的放在事件处理过程中
...
PictureBox1.Image.Save("D:/1.jpg")
...

Answer 3

6.0 有 savepicture 函数 net 有吗