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因为我需要从文件中提取图标,但不是第一个图标,所以我无法使用vb.net图标提取功能。应该这样做的WIN32API函数需要一个指向整型数组的指针。vb.net win32api指向整数数组参数
我该如何提供这种类型作为参数?
Declare Function ExtractIconEx Lib "shell32.dll" Alias "ExtractIconExA" _
(ByVal lpszFile As String, _
ByVal nIconIndex As Integer, _
ByRef phiconLarge As Integer, _
ByRef phiconSmall As Integer, _
ByVal nIcons As Long) As Integer
Dim icons As integer()
ExtractIconEx("%systemroot%/shell32.dll", 15, icons, 0, 5)
我已经采取甘德在System.Reflection.Pointer
类?/?的命名空间,但文件是稀疏的和小于明智的。
IntPtr
不会对数组汉斯提供支持afaikt
正常Tx我已经设法纠正签名:
<Runtime.InteropServices.DllImport("shell32.dll", _
CharSet:=Runtime.InteropServicesCharSet.Auto)> _
Shared Function ExtractIconEx(ByVal szFileName As String, _
ByVal nIconIndex As Integer, _
ByRef phiconLarge() As IntPtr, _
ByRef phiconSmall() As IntPtr, _
ByVal nIcons As UInteger) As UInteger
End Function
...
Dim icons(8) As IntPtr, smicons(8) As IntPtr
MsgBox(ExtractIconEx("%systemroot%/shell32.dll", 15, icons, smicons, 1))
Try
MsgBox(icons.Count)
Catch ex As Exception
MsgBox(ex.Message & " by " & ex.Source)
End Try
...
随后的电话始终会导致异常(Value cannot be null
)。我得到一个返回值4294967295
,这是最大的32位整数值。
任何想法如何驯服这个功能,并使其工作?
http://pinvoke.net/default.aspx/shell32/ExtractIconEx.html –