vb.net InternetFindNextFile

在 VB.NET 中，InternetFindNextFile 函数用于在 Internet 连接中查找下一个文件或子目录。该函数通常与 InternetFindFirstFile 函数一起使用，用于遍历 Internet 连接中的文件和目录。

以下是一个示例代码，演示如何使用 InternetFindNextFile 函数：

Imports System
Imports System.Net

Module Module1
    Sub Main()
        ' 创建一个 Internet 连接
        Dim hInternet As IntPtr = InternetOpen("MyApp", INTERNET_OPEN_TYPE_DIRECT, Nothing, Nothing, 0)
        If hInternet <> IntPtr.Zero Then
            ' 打开一个目录
            Dim hConnect As IntPtr = InternetOpenUrl(hInternet, "http://www.example.com", Nothing, 0, INTERNET_FLAG_RELOAD, 0)
            If hConnect <> IntPtr.Zero Then
                Dim findData As WIN32_FIND_DATA
                ' 查找第一个文件或子目录
                Dim hFind As IntPtr = InternetFindFirstFile(hConnect, findData, 0, 0)
                If hFind <> IntPtr.Zero Then
                    Do
                        ' 处理找到的文件或子目录
                        Console.WriteLine("Found file: " + findData.cFileName)
                        ' 继续查找下一个文件或子目录
                    Loop While InternetFindNextFile(hFind, findData)

                    ' 关闭句柄
                    InternetCloseHandle(hFind)
                Else
                    Console.WriteLine("InternetFindFirstFile failed")
                End If

                ' 关闭句柄
                InternetCloseHandle(hConnect)
            Else
                Console.WriteLine("InternetOpenUrl failed")
            End If

            ' 关闭句柄
            InternetCloseHandle(hInternet)
        Else
            Console.WriteLine("InternetOpen failed")
        End If

        Console.ReadLine()
    End Sub

    ' 导入相关的 Win32 API 函数
    Private Declare Function InternetOpen Lib "wininet.dll" Alias "InternetOpenA" (ByVal lpszAgent As String, ByVal dwAccessType As Integer, ByVal lpszProxyName As String, ByVal lpszProxyBypass As String, ByVal dwFlags As Integer) As IntPtr
    Private Declare Function InternetOpenUrl Lib "wininet.dll" Alias "InternetOpenUrlA" (ByVal hInternetSession As IntPtr, ByVal lpszUrl As String, ByVal lpszHeaders As String, ByVal dwHeadersLength As Integer, ByVal dwFlags As Integer, ByVal dwContext As Integer) As IntPtr
    Private Declare Function InternetFindFirstFile Lib "wininet.dll" Alias "InternetFindFirstFileA" (ByVal hConnect As IntPtr, ByRef lpFindFileData As WIN32_FIND_DATA, ByVal dwFlags As Integer, ByVal dwContext As Integer) As IntPtr
    Private Declare Function InternetFindNextFile Lib "wininet.dll" Alias "InternetFindNextFileA" (ByVal hFind As IntPtr, ByRef lpFindFileData As WIN32_FIND_DATA) As Boolean
    Private Declare Function InternetCloseHandle Lib "wininet.dll" (ByVal hInet As IntPtr) As Boolean

    ' 定义 WIN32_FIND_DATA 结构体
    Structure WIN32_FIND_DATA
        Public dwFileAttributes As Integer
        Public ftCreationTime As Long
        Public ftLastAccessTime As Long
        Public ftLastWriteTime As Long
        Public nFileSizeHigh As Integer
        Public nFileSizeLow As Integer
        Public dwReserved0 As Integer
        Public dwReserved1 As Integer
        <VBFixedString(260), System.Runtime.InteropServices.MarshalAs(System.Runtime.InteropServices.UnmanagedType.ByValTStr, SizeConst:=260)> Public cFileName As String
        <VBFixedString(14), System.Runtime.InteropServices.MarshalAs(System.Runtime.InteropServices.UnmanagedType.ByValTStr, SizeConst:=14)> Public cAlternate As String
    End Structure

    ' 定义常量
    Private Const INTERNET_OPEN_TYPE_DIRECT As Integer = 1
    Private Const INTERNET_FLAG_RELOAD As Integer = &H80000000
End Module

请注意，以上示例代码仅演示了如何使用 InternetFindNextFile 函数来遍历 Internet 连接中的文件和目录。根据你的实际需求，你可能需要进行更多的错误处理和逻辑处理。