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picturebox中图片放大缩小问题

楼主scorpions215（asdf）2003-12-03 16:44:34 在 VB / 基础类提问

在picture1中，用鼠标mousedown时有（x1，y1），mouseup时(x2,y2),怎么把鼠标圈住的里面的内容放大到整个picturebox中去？
问题点数：50、回复次数：10Top

1 楼TechnoFantasy（（VB MVP）www.applevb.com）回复于 2003-12-03 16:54:04 得分 25

Private Declare Function StretchBlt Lib "gdi32" _
(ByVal hdc As Long, ByVal X As Long, ByVal Y As Long, _
ByVal nWidth As Long, ByVal nHeight As Long, ByVal hSrcDC As Long, _
ByVal xSrc As Long, ByVal ySrc As Long, _
ByVal nSrcWidth As Long, ByVal nSrcHeight As Long, ByVal dwRop As Long) As Long
Private Const SRCCOPY = &HCC0020 ' (DWORD) dest = source

Dim x1 As Long
Dim y1 As Long
Dim x2 As Long
Dim y2 As Long

Private Sub Form_Load()
Picture1.ScaleMode = 3
End Sub

Private Sub Picture1_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
x1 = CLng(X)
y1 = CLng(Y)
End Sub

Private Sub Picture1_MouseUp(Button As Integer, Shift As Integer, X As Single, Y As Single)
x2 = CLng(X)
y2 = CLng(Y)

StretchBlt Picture1.hdc, 0, 0, Picture1.Width / 15, Picture1.Height / 15, Picture1.hdc, x1, y1, x2 - x1, y2 - y1, SRCCOPY
End Sub
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2 楼scorpions215（asdf）回复于 2003-12-04 08:35:10 得分 0

一定要scalemodel=3么？我scalemodel=0行不行的
我是用scalemodel画出来的图，想把它放大的Top

3 楼szyhy810518（)(）回复于 2003-12-04 08:58:27 得分 0

StretchBlt Picture1.hdc, 0, 0, Picture1.Width / 15, Picture1.Height / 15, Picture1.hdc, x1, y1, x2 - x1, y2 - y1, SRCCOPY

我要是得到这个函数的返回值好像就不会正确执行?Top

4 楼szyhy810518（)(）回复于 2003-12-04 08:59:34 得分 0

是跟踪调试的时候不会正确执行Top

5 楼scorpions215（asdf）回复于 2003-12-04 09:03:39 得分 0

for i=1 to 10
picture1.line(m(i,1),m(i,2))-m(i-1,1)m(i-1,2)
next
的时候
要这线在（x1,y1),(x2,y2)
范围内画出来，超出范围的不画，怎么做？Top

6 楼szyhy810518（)(）回复于 2003-12-04 09:18:42 得分 25

Private Sub Picture1_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
x1 = CLng(X)
y1 = CLng(Y)
blnMove = True
End Sub

Private Sub Picture1_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
'应该是在（x1,y1),(x,y)范围内吧!

If blnMove Then
With Line1(0)
.x1 = x1
.y1 = y1
.x2 = x1
.y2 = Y
End With
With Line1(1)
.x1 = x1
.y1 = y1
.x2 = X
.y2 = y1
End With
With Line1(2)
.x1 = X
.y1 = y1
.x2 = X
.y2 = Y
End With
With Line1(3)
.x1 = x1
.y1 = Y
.x2 = X
.y2 = Y
End With
End If

Label1.Caption = X & Space(10) & Y

End Sub

Private Sub Picture1_MouseUp(Button As Integer, Shift As Integer, X As Single, Y As Single)

Dim iIndex As Integer
Dim lngResult As Long

x2 = CLng(X)
y2 = CLng(Y)

'StretchBlt Picture1.hdc, 0, 0, Picture1.Width / 15, Picture1.Height / 15, Picture1.hdc, x1, y1, x2 - x1, y2 - y1, SRCCOPY

lngResult = StretchBlt(Picture1.hdc, 0, 0, Picture1.Width / 15, Picture1.Height / 15, Picture1.hdc, x1, y1, x2 - x1, y2 - y1, SRCCOPY)

If lngResult = 0 Then
MsgBox "ＦＤｆ"
End If

For iIndex = 0 To 3
With Line1(iIndex)
.x1 = 0
.y1 = 0
.x2 = 0
.y2 = 0
End With
Next

blnMove = False
Picture1.Refresh

End Sub

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7 楼szyhy810518（)(）回复于 2003-12-04 09:28:20 得分 0

如何获得图片已经扩大到不能再扩大,即使整个picture1都显示一种颜色?Top

8 楼scorpions215（asdf）回复于 2003-12-04 09:39:46 得分 0

比如我picture1.scale(0,0)-(1000,1000)的时候
for i=1 to 10
picture1.line(m(i,1),m(i,2))-m(i-1,1)m(i-1,2)
next
的时候
要这线在（100,100),(800,800)
范围内画出来，可能有线（700，700）-（900，900）
我要在范围内的显示，超出的不显示用你刚才的方法可以么？
Top

9 楼scorpions215（asdf）回复于 2003-12-04 09:41:15 得分 0

我刚才说的图片不要放大了，就在范围内画线Top

10 楼scorpions215（asdf）回复于 2003-12-04 09:45:45 得分 0

是不是用pset的方法可以？还有没有别的方法Top