vb 该内存不能为read求助?

[nanfei01055]

最近在用vb做一个关于图片保存为jpg,gif格式的程序,从网上下了一段代码,用起来倒是很方便,效果很理想,可以保存,但有一个很大的问题就是,执行了这段代码后,图片是保存成功了,vb却崩溃了,执行完之后,只要托运一下vb下的代码窗口,或一会就会自动弹出"XXX引用的内在不能为read",之后,我想经常用api的人都会知道,是什么结果了.特此向大家求助.

说明:因我所转换的都是jpg文件,最有可能的是加粗部分,所以大家只要帮看下问题出在哪一句上,怎么解决,多谢,可能分不够,还请谅解?

我的文件的其它地方没有用过api,之前也非常正常,只是使用了这段代码之后出现问题,所有我可以断定问题出在这里.

Private Type GUID
Data1 As Long
Data2 As Integer
Data3 As Integer
Data4(0 To 7) As Byte
End Type
Private Type GdiplusStartupInput
GdiplusVersion As Long
DebugEventCallback As Long
SuppressBackgroundThread As Long
SuppressExternalCodecs As Long
End Type
Private Type EncoderParameter
GUID As GUID
NumberOfValues As Long
type As Long
Value As Long
End Type
Private Type EncoderParameters
count As Long
Parameter As EncoderParameter
End Type

Private Declare Function GdiplusStartup Lib "GDIPlus" (token As Long, inputbuf As GdiplusStartupInput, Optional ByVal outputbuf As Long = 0) As Long
Private Declare Function GdiplusShutdown Lib "GDIPlus" (ByVal token As Long) As Long
Private Declare Function GdipCreateBitmapFromHBITMAP Lib "GDIPlus" (ByVal hbm As Long, ByVal hPal As Long, BITMAP As Long) As Long
Private Declare Function GdipDisposeImage Lib "GDIPlus" (ByVal Image As Long) As Long
Private Declare Function GdipSaveImageToFile Lib "GDIPlus" (ByVal Image As Long, ByVal FileName As Long, clsidEncoder As GUID, encoderParams As Any) As Long
Private Declare Function CLSIDFromString Lib "ole32" (ByVal Str As Long, id As GUID) As Long
Private Declare Function CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Dest As Any, Src As Any, ByVal cb As Long) As Long

'*************************************************************************
'** 作 者 ： laviewpbt
'** 函 数 名 ： SavePic
'** 输 入 ： pic(StdPicture) - 图象句柄
'** ： FileName(String) - 保存路径
'** ： Quality(Byte) - JPG图象质量
'** ： TIFF_ColorDepth(Long) - TTF格式的颜色深度
'** ： TIFF_Compression(Long) - TTF格式的压缩比
'** 输 出 ： 无
'** 功能描述 ： 把图象保存为JPG、TIFF、PNG、GIF、BMP格式
'** 日 期 ：
'** 修 改 人 ： laviewpbt
'** 日 期 ： 2005-10-23 14.43.52
'** 版 本 ： Version 1.2.1
'*************************************************************************
Public Sub SavePic(ByVal pict As StdPicture, ByVal FileName As String, PicType As String, _
Optional ByVal Quality As Byte = 80, _
Optional ByVal TIFF_ColorDepth As Long = 24, _
Optional ByVal TIFF_Compression As Long = 6)
Dim tSI As GdiplusStartupInput
Dim lRes As Long
Dim lGDIP As Long
Dim lBitmap As Long
Dim aEncParams() As Byte
On Error GoTo ErrHandle:
tSI.GdiplusVersion = 1 ' 初始化 GDI+
lRes = GdiplusStartup(lGDIP, tSI)
If lRes = 0 Then ' 从句柄创建 GDI+ 图像
lRes = GdipCreateBitmapFromHBITMAP(pict.Handle, 0, lBitmap)
If lRes = 0 Then
Dim tJpgEncoder As GUID
Dim tParams As EncoderParameters '初始化解码器的GUID标识
Select Case PicType
Case ".jpg"
CLSIDFromString StrPtr("{557CF401-1A04-11D3-9A73-0000F81EF32E}"), tJpgEncoder
tParams.count = 1 ' 设置解码器参数
With tParams.Parameter ' Quality
CLSIDFromString StrPtr("{1D5BE4B5-FA4A-452D-9CDD-5DB35105E7EB}"), .GUID ' 得到Quality参数的GUID标识
.NumberOfValues = 1
.type = 4
.Value = VarPtr(Quality)
End With
ReDim aEncParams(1 To Len(tParams))
Exit Sub
Call CopyMemory(aEncParams(1), tParams, Len(tParams))
Case ".png"
CLSIDFromString StrPtr("{557CF406-1A04-11D3-9A73-0000F81EF32E}"), tJpgEncoder
ReDim aEncParams(1 To Len(tParams))
Case ".gif"
CLSIDFromString StrPtr("{557CF402-1A04-11D3-9A73-0000F81EF32E}"), tJpgEncoder
ReDim aEncParams(1 To Len(tParams))
Case ".tiff"
CLSIDFromString StrPtr("{557CF405-1A04-11D3-9A73-0000F81EF32E}"), tJpgEncoder
tParams.count = 2
ReDim aEncParams(1 To Len(tParams) + Len(tParams.Parameter))
With tParams.Parameter
.NumberOfValues = 1
.type = 4
CLSIDFromString StrPtr("{E09D739D-CCD4-44EE-8EBA-3FBF8BE4FC58}"), .GUID ' 得到ColorDepth参数的GUID标识
.Value = VarPtr(TIFF_Compression)
End With
Call CopyMemory(aEncParams(1), tParams, Len(tParams))
With tParams.Parameter
.NumberOfValues = 1
.type = 4
CLSIDFromString StrPtr("{66087055-AD66-4C7C-9A18-38A2310B8337}"), .GUID ' 得到Compression参数的GUID标识
.Value = VarPtr(TIFF_ColorDepth)
End With
Call CopyMemory(aEncParams(Len(tParams) + 1), tParams.Parameter, Len(tParams.Parameter))
Case ".bmp" '可以提前写保存为BMP的代码，因为并没有用GDI+
SavePicture pict, FileName
Screen.MousePointer = vbDefault
Exit Sub
End Select
lRes = GdipSaveImageToFile(lBitmap, StrPtr(FileName), tJpgEncoder, aEncParams(1)) '保存图像
GdipDisposeImage lBitmap ' 销毁GDI+图像
End If
GdiplusShutdown lGDIP '销毁 GDI+
End If
Erase aEncParams
Exit Sub
ErrHandle:
MsgBox "在保存图片的过程中发生错误:" & vbCrLf & vbCrLf & "错误号: " & Err.Number & vbCrLf & "错误描述: " & Err.Description, vbOKOnly, "错误"
End Sub

[pvgyetg]

是不是主机问题啊,我以前也出现过这个问题,装了系统后就没有了,

[nanfei01055]

可能性不大吧?我现在一直在用VB做东西,也遇到过这种问题,经检查都是程序写得有问题,这次测试了好多次,不知道是哪句有问题,还是该传值的地方把地址给传进去了,还是别的,望高手指导.

[nanfei01055]

补充一句,运行次数如果过多的话,比如我就用它一口气保存了30张图片,机子直接蓝屏.

[nicon]

应该是API问题，调用完后要释放相关对象。

[barenx]

Private Declare Function CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (Dest As Any, Src As Any, ByVal cb As Long) As Long 
'请严格使用copyMemory，两个内存指针，一个长度
Private Declare Function CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (byval Dest As long,byval Src As long, ByVal cb As Long) As Long 
'使用vatptr、objptr（需要声明）、strptr获得相应变量的内存指针

[nanfei01055]

问题已解决,原来上面的代码也是参考别人改过来的,我看了原文,自己改了下,就好了.