Attribute VB_Name = "modWinInet"
Option Explicit

'打開Internet連接，得到其它WinInet函數所用的句柄
Public Declare Function InternetOpen Lib "wininet.dll" Alias "InternetOpenA" _
(ByVal sAgent As String, ByVal lAccessType As Long, ByVal sProxyName As String, _
ByVal sProxyBypass As String, ByVal lFlags As Long) As Long

'字符串常量
Public Const scUserAgent = "DownJetApi"

'使用注冊表中的設置
Public Const INTERNET_OPEN_TYPE_PRECONFIG = 0
Public Const INTERNET_OPEN_TYPE_PROXY = 1

'打開Http連接會話
Public Declare Function InternetConnect Lib "wininet.dll" Alias "InternetConnectA" _
(ByVal hInternetSession As Long, ByVal sServerName As String, ByVal nServerPort As Integer, _
ByVal sUsername As String, ByVal sPassword As String, ByVal lService As Long, _
ByVal lFlags As Long, ByVal lContext As Long) As Long

'TCP/IP的端口
Public Const INTERNET_DEFAULT_FTP_PORT = 21
Public Const INTERNET_DEFAULT_GOPHER_PORT = 70
Public Const INTERNET_DEFAULT_HTTP_PORT = 80
Public Const INTERNET_DEFAULT_HTTPS_PORT = 443
Public Const INTERNET_DEFAULT_SOCKS_PORT = 1080

'請求的服務
Public Const INTERNET_SERVICE_FTP = 1
Public Const INTERNET_SERVICE_GOPHER = 2
Public Const INTERNET_SERVICE_HTTP = 3

'打開Http請求
Public Declare Function HttpOpenRequest Lib "wininet.dll" Alias "HttpOpenRequestA" _
(ByVal hHttpSession As Long, ByVal sVerb As String, ByVal sObjectName As String, ByVal sVersion As String, _
ByVal sReferer As String, ByVal something As Long, ByVal lFlags As Long, ByVal lContext As Long) As Long

'不從Cache下載數據
Public Const INTERNET_FLAG_RELOAD = &H80000000

'向HTTP服務器發送請求
Public Declare Function HttpSendRequest Lib "wininet.dll" Alias "HttpSendRequestA" (ByVal _
hHttpRequest As Long, ByVal sHeaders As String, ByVal lHeadersLength As Long, sOptional As _
Any, ByVal lOptionalLength As Long) As Integer

'取得請求或響應的標題字段
Public Declare Function HttpQueryInfo Lib "wininet.dll" Alias "HttpQueryInfoA" _
(ByVal hHttpRequest As Long, ByVal lInfoLevel As Long, ByRef sBuffer As Any, _
ByRef lBufferLength As Long, ByRef lIndex As Long) As Integer

' HttpQueryInfo的lInfoLevel的值
Public Const HTTP_QUERY_CONTENT_TYPE = 1
Public Const HTTP_QUERY_CONTENT_LENGTH = 5
Public Const HTTP_QUERY_EXPIRES = 10
Public Const HTTP_QUERY_LAST_MODIFIED = 11
Public Const HTTP_QUERY_PRAGMA = 17
Public Const HTTP_QUERY_VERSION = 18
Public Const HTTP_QUERY_STATUS_CODE = 19
Public Const HTTP_QUERY_STATUS_TEXT = 20
Public Const HTTP_QUERY_RAW_HEADERS = 21
Public Const HTTP_QUERY_RAW_HEADERS_CRLF = 22
Public Const HTTP_QUERY_FORWARDED = 30
Public Const HTTP_QUERY_SERVER = 37
Public Const HTTP_QUERY_USER_AGENT = 39
Public Const HTTP_QUERY_SET_COOKIE = 43
Public Const HTTP_QUERY_REQUEST_METHOD = 45

'取得請求標題字段的標志
Public Const HTTP_QUERY_FLAG_REQUEST_HEADERS = &H80000000

'從HttpOpenRequest函數打開的URL請求中讀取數據
Public Declare Function InternetReadFile Lib "wininet.dll" _
(ByVal hFile As Long, ByVal sBuffer As String, ByVal lNumBytesToRead As Long, _
lNumberOfBytesRead As Long) As Integer

'從HttpOpenRequest函數打開的URL請求中讀取數據(用于讀取二進制文件）
Public Declare Function InternetReadImg Lib "wininet.dll" Alias "InternetReadFile" _
        (ByVal hFile As Long, lpBuffer As Any, ByVal dwNumberOfBytesToRead As Long, _
         lNumberOfBytesRead As Long) As Integer

'關閉WinInet函數打開的句柄
Public Declare Function InternetCloseHandle Lib "wininet.dll" _
(ByVal hInet As Long) As Integer

'用于獲得或設置Internet選項
Public Declare Function InternetQueryOption Lib "wininet.dll" Alias "InternetQueryOptionA" _
(ByVal hInternet As Long, ByVal lOption As Long, ByRef sBuffer As Any, ByRef lBufferLength As Long) As Integer

'函數InternetQueryOption的lOption參數值，用于返回WinInet函數的版本信息
Public Const INTERNET_OPTION_VERSION = 40

'函數InternetQueryOption的sBuffer參數值，包含版本信息的類型
Public Type tWinInetDLLVersion
    lMajorVersion As Long
    lMinorVersion As Long
End Type

'增加請求的標題字段
Public Declare Function HttpAddRequestHeaders Lib "wininet.dll" Alias "HttpAddRequestHeadersA" _
(ByVal hHttpRequest As Long, ByVal sHeaders As String, ByVal lHeadersLength As Long, _
ByVal lModifiers As Long) As Integer

'函數HttpAddRequestHeaders的lModifiers參數值
'請求的標題字段不存在時才增加，否則出錯
Public Const HTTP_ADDREQ_FLAG_ADD_IF_NEW = &H10000000

'請求的標題字段不存在時增加，否則更新
Public Const HTTP_ADDREQ_FLAG_ADD = &H20000000

'如果標題字段的值為空，則刪除，不為空則代替
Public Const HTTP_ADDREQ_FLAG_REPLACE = &H80000000