主题：[求助] 获取文件对应的图标

 查了一下资料，发觉原来直接用就可以了

Dim icon As Icon = System.Drawing.Icon.ExtractAssociatedIcon("d:\test.xls")

'直接使用icon

'Dim fileStream As new System.IO.FileStream("d:\test.ico", System.IO.FileMode.Create)
'icon.Save(fileStream)
'fileStream.Close()

根据后缀名得到的，参考

全局代码

<System.Runtime.InteropServices.DllImportAttribute("shell32.dll", EntryPoint := "ExtractIconExW", CallingConvention := System.Runtime.InteropServices.CallingConvention.StdCall)> _
Public Function ExtractIconExW(<System.Runtime.InteropServices.InAttribute> <System.Runtime.InteropServices.MarshalAsAttribute(System.Runtime.InteropServices.UnmanagedType.LPWStr)> lpszFile As String, nIconIndex As Integer, ByRef phiconLarge As System.IntPtr, ByRef phiconSmall As System.IntPtr, nIcons As UInteger) As UInteger
End Function

------------

获取代码

Dim extsubkey = Registry.ClassesRoot.OpenSubKey(".xls")
'从注册表中读取扩展名相应的子键
If extsubkey IsNot Nothing Then
    Dim extdefaultvalue = DirectCast(extsubkey.GetValue(Nothing), String)
    '取出扩展名对应的文件类型名称
    Dim typesubkey = Registry.ClassesRoot.OpenSubKey(extdefaultvalue)
    '从注册表中读取文件类型名称的相应子键
    If typesubkey IsNot Nothing Then
        Dim description = DirectCast(typesubkey.GetValue(Nothing), String)
        '得到类型描述字符串
        Dim defaulticonsubkey = typesubkey.OpenSubKey("DefaultIcon")
        '取默认图标子键
        If defaulticonsubkey IsNot Nothing Then
            '得到图标来源字符串
            Dim defaulticon = DirectCast(defaulticonsubkey.GetValue(Nothing), String)
            '取出默认图标来源字符串
            Dim iconstringArray = defaulticon.Split(","C)
            Dim nIconIndex As Integer = 0
            If iconstringArray.Length > 1 Then
                Integer.TryParse(iconstringArray(1), nIconIndex)
            End If
            '得到图标
           
            Dim phiconLarge As new System.IntPtr
            Dim phiconSmall As new System.IntPtr
            ExtractIconExW(iconstringArray(0).Trim(""""C), nIconIndex, phiconLarge, phiconSmall, 1)
            Dim icon As icon = Icon.FromHandle(phiconLarge)
            Dim fileStream As new System.IO.FileStream("d:\test.ico", System.IO.FileMode.Create)
            icon.Save(fileStream)
            fileStream.Close()
        End If
    End If
End If

提取Icon保存为.ico格式，就是有偏差的，如果你要完整的，可以保存成图片

Dim icon As Icon = System.Drawing.Icon.ExtractAssociatedIcon("d:\test.xls")
icon.ToBitmap().save("d:\aaaaaa.ico")

什么意思？这个保存后不是ico格式，是图片格式。

ftp上的文件？

方法1：用后缀名的方式获取；

方法2：把文件下载，再获取。