设置IE代理

#Region "改变代理"
    Private Structure Struct_INTERNET_PROXY_INFO
        Public dwAccessType As Integer
        Public proxy As IntPtr
        Public proxyBypass As IntPtr
    End Structure

    <Runtime.InteropServices.DllImport("wininet.dll", SetLastError:=True)> _
    Private Shared Function InternetSetOption(ByVal hInternet As IntPtr, ByVal dwOption As Integer, ByVal lpBuffer As IntPtr, ByVal lpdwBufferLength As Integer) As Boolean
    End Function

    Public Shared Sub SetProxy(Optional ByVal strProxy As String = "221.130.7.227:80")
        Const INTERNET_OPTION_PROXY As Integer = 38
        Const INTERNET_OPEN_TYPE_PROXY As Integer = 3

        Dim struct_IPI As Struct_INTERNET_PROXY_INFO

        ' Filling in structure 
        struct_IPI.dwAccessType = INTERNET_OPEN_TYPE_PROXY
        struct_IPI.proxy = Marshal.StringToHGlobalAnsi(strProxy)
        struct_IPI.proxyBypass = Marshal.StringToHGlobalAnsi("local")

        ' Allocating memory 
        Dim intptrStruct As IntPtr = Marshal.AllocCoTaskMem(Marshal.SizeOf(struct_IPI))

        ' Converting structure to IntPtr 
        Marshal.StructureToPtr(struct_IPI, intptrStruct, True)

        Dim iReturn As Boolean = InternetSetOption(IntPtr.Zero, INTERNET_OPTION_PROXY, intptrStruct, Marshal.SizeOf(struct_IPI))
    End Sub
#End Region