用vb60使用wininet 实现httpsocket例子

以下是使用VB6.0和Wininet实现HTTPSocket的示例代码：

Private Declare Function InternetOpen Lib "wininet.dll" Alias "InternetOpenA" (ByVal lpszAgent As String, ByVal dwAccessType As Long, ByVal lpszProxyName As String, ByVal lpszProxyBypass As String, ByVal dwFlags As Long) As Long
Private Declare Function InternetConnect Lib "wininet.dll" Alias "InternetConnectA" (ByVal hInternetSession As Long, ByVal lpszServerName As String, ByVal nServerPort As Integer, ByVal lpszUsername As String, ByVal lpszPassword As String, ByVal dwService As Long, ByVal dwFlags As Long, ByVal dwContext As Long) As Long
Private Declare Function HttpOpenRequest Lib "wininet.dll" Alias "HttpOpenRequestA" (ByVal hHttpSession As Long, ByVal lpszVerb As String, ByVal lpszObjectName As String, ByVal lpszVersion As String, ByVal lpszReferer As String, ByVal lplpszAcceptTypes As Long, ByVal dwFlags As Long, ByVal dwContext As Long) As Long
Private Declare Function HttpSendRequest Lib "wininet.dll" Alias "HttpSendRequestA" (ByVal hHttpRequest As Long, ByVal lpszHeaders As String, ByVal dwHeadersLength As Long, ByVal lpOptional As Any, ByVal dwOptionalLength As Long) As Long
Private Declare Function InternetReadFile Lib "wininet.dll" (ByVal hFile As Long, ByVal lpBuffer As String, ByVal dwNumberOfBytesToRead As Long, lpNumberOfBytesRead As Long) As Integer
Private Declare Function HttpQueryInfo Lib "wininet.dll" Alias "HttpQueryInfoA" (ByVal hHttpRequest As Long, ByVal dwInfoLevel As Long, lpBuffer As Any, lpdwBufferLength As Long, ByVal lpdwIndex As Long) As Long
Private Declare Function InternetCloseHandle Lib "wininet.dll" (ByVal hInet As Long) As Integer

Public Sub HTTPSocket()
    Dim hInternetSession As Long
    Dim hHttpSession As Long
    Dim hHttpRequest As Long
    Dim sServerName As String
    Dim sObjectName As String
    Dim sBuffer As String
    Dim sHeaders As String
    Dim iPort As Integer
    Dim iRet As Integer
    Dim iBufferSize As Long
    Dim iIndex As Long
    
    ' 初始化Internet会话
    hInternetSession = InternetOpen("VB6 Wininet Example", 0, vbNullString, vbNullString, 0)
    
    ' 连接服务器
    sServerName = "www.example.com"
    iPort = 80
    hHttpSession = InternetConnect(hInternetSession, sServerName, iPort, vbNullString, vbNullString, 3, 0, 0)
    
    ' 请求页面
    sObjectName = "/index.html"
    sHeaders = "Accept: */*" & vbCrLf & "User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0)"
    hHttpRequest = HttpOpenRequest(hHttpSession, "GET", sObjectName, "HTTP/1.0", vbNullString, 0, 0, 0)
    HttpSendRequest hHttpRequest, sHeaders, Len(sHeaders), 0, 0
    
    ' 读取页面内容
    iBufferSize = 1024
    sBuffer = Space$(iBufferSize)
    iRet = InternetReadFile(hHttpRequest, sBuffer, iBufferSize, iBufferSize)
    Do While iRet <> 0
        ' 处理读取到的数据
        Debug.Print Left$(sBuffer, iRet)
        iRet = InternetReadFile(hHttpRequest, sBuffer, iBufferSize, iBufferSize)
    Loop
    
    ' 获取响应头信息
    iBufferSize = 1024
    sBuffer = Space$(iBufferSize)
    iIndex = 0
    HttpQueryInfo hHttpRequest, 2, ByVal sBuffer, iBufferSize, iIndex
    Debug.Print "Content-Type: " & Left$(sBuffer, iBufferSize)
    
    ' 关闭请求和会话
    InternetCloseHandle hHttpRequest
    InternetCloseHandle hHttpSession
    
    ' 关闭Internet会话
    InternetCloseHandle hInternetSession
End Sub

此代码将连接到www.example.com并请求/index.html页面。它将读取响应并打印到调试窗口中，并获取响应头信息并将其打印到调试窗口中。请注意，此代码仅用于演示目的，实际应用程序可能需要更多的错误处理和异常情况处理