Как загрузить изображение с WEB страницы, не используя его URL адрес - VB

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Формулировка задачи:

Задача: есть адрес веб-страницы, на которой расположена картинка. Эта картинка при обновлении страницы меняется (скажем так - это каптча с постоянным URL-адресом). Как программно сохранить ее на диск? Для работы со страницей использую объект "InternetExplorer.Application"

Не по теме:

С Webbrowser какие-то проблемы. При проверке свойств .busy и .readystate

иногда

с вероятностью 50 % появляется ошибка "object does not support this property or method".

Я нашел класс для работы с кешем, но пока не разобрался, как ним пользоваться и умеет ли он "вытягивать" картинки.
Листинг программы 
  1. Option Explicit
  2.  
  3. Private Const LMEM_FIXED As Long = &H0
  4. Private Const LMEM_ZEROINIT As Long = &H40
  5.  
  6. Private Type FILETIME
  7.     lLowDateTime As Long
  8.     lHighDateTime As Long
  9. End Type
  10.  
  11. Private Type SYSTEMTIME
  12.         wYear As Integer
  13.         wMonth As Integer
  14.         wDayOfWeek As Integer
  15.         wDay As Integer
  16.         wHour As Integer
  17.         wMinute As Integer
  18.         wSecond As Integer
  19.         wMilliseconds As Integer
  20. End Type
  21.  
  22. Private Type INTERNET_CACHE_ENTRY_INFO
  23.    dwStructSize As Long
  24.    lpszSourceUrlName As Long
  25.    lpszLocalFileName As Long
  26.    CacheEntryType As Long
  27.    dwUseCount As Long
  28.    dwHitRate As Long
  29.    dwSizeLow As Long
  30.    dwSizeHigh As Long
  31.    LastModifiedTime As FILETIME
  32.    ExpireTime As FILETIME
  33.    LastAccessTime As FILETIME
  34.    LastSyncTime As FILETIME
  35.    lpHeaderInfo As Long
  36.    dwHeaderInfoSize As Long
  37.    lpszFileExtension As Long
  38.    dwExemptDelta As Long
  39. End Type
  40.  
  41. Private Declare Function FindFirstUrlCacheEntry Lib "wininet.dll" Alias "FindFirstUrlCacheEntryA" ( _
  42.         ByVal lpszSearchPattern As String, _
  43.         ByVal lpCacheInfo As Long, _
  44.         lpdwFirstCacheEntryInfoBufferSize As Long) As Long
  45.     
  46. Private Declare Function FindNextUrlCacheEntry Lib "wininet.dll" Alias "FindNextUrlCacheEntryA" ( _
  47.         ByVal hEnumHandle As Long, _
  48.         ByVal lpCacheInfo As Long, _
  49.         lpdwNextCacheEntryInfoBufferSize As Long) As Long
  50.  
  51. Private Declare Function FindCloseUrlCache Lib "wininet.dll" ( _
  52.         ByVal hEnumHandle As Long) As Long
  53.         
  54. Private Declare Function GetUrlCacheEntryInfo Lib "wininet.dll" Alias "GetUrlCacheEntryInfoA" ( _
  55.         ByVal lpszUrlName As String, _
  56.         ByVal lpCacheInfo As Long, _
  57.         lpdwCacheEntryInfoBufferSize As Long) As Long
  58.  
  59. Private Declare Function DeleteUrlCacheEntry Lib "wininet.dll" Alias "DeleteUrlCacheEntryA" ( _
  60.         ByVal lpszUrlName As String) As Long
  61.     
  62. Private Declare Function PtrToStr Lib "kernel32" Alias "lstrcpyA" (ByVal RetVal As String, ByVal Ptr As Long) As Long
  63. Private Declare Function FileTimeToSystemTime Lib "kernel32" (lpFileTime As FILETIME, lpSystemTime As SYSTEMTIME) As Long
  64. Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (pDest As Any, pSource As Any, ByVal dwLength As Long)
  65. Private Declare Function LocalAlloc Lib "kernel32" (ByVal uFlags As Long, ByVal uBytes As Long) As Long
  66. Private Declare Function LocalFree Lib "kernel32" (ByVal hMem As Long) As Long
  67. Private Declare Function lstrcpyA Lib "kernel32" (ByVal RetVal As String, ByVal Ptr As Long) As Long
  68. Private Declare Function lstrlenA Lib "kernel32" (ByVal Ptr As Any) As Long
  69.   
  70. Private hEnumHandle As Long
  71. Private ci As INTERNET_CACHE_ENTRY_INFO
  72. Private lPtrCI As Long
  73.  
  74. Public Property Get CachedEntryCacheType() As Long
  75.     CachedEntryCacheType = ci.CacheEntryType
  76. End Property
  77.  
  78. Public Property Get CachedEntryExpireTime() As Date
  79. On Local Error Resume Next
  80. Dim dExpire As Date
  81. Dim stSystemTime As SYSTEMTIME
  82. Dim lReturnValue As Long
  83.     lReturnValue = FileTimeToSystemTime(ci.ExpireTime, stSystemTime)
  84.     With stSystemTime
  85.         dExpire = CDate(.wMonth & "/" & .wDay & "/" & .wYear & " " & .wHour & ":" & .wMinute & ":" & .wSecond)
  86.     End With
  87.     CachedEntryExpireTime = dExpire
  88. End Property
  89.  
  90. Public Property Get CachedEntryFileExtension() As String
  91. Dim strData As String
  92. Dim lReturnValue As Long
  93. Dim iPosition As Long
  94.     strData = Space(250)
  95.     lReturnValue = PtrToStr(strData, ci.lpszFileExtension)
  96.     If lReturnValue Then
  97.         iPosition = InStr(strData, Chr(0))
  98.         CachedEntryFileExtension = Left$(strData, iPosition - 1)
  99.     End If
  100. End Property
  101.  
  102. Public Property Get CachedEntryLastAccessTime() As Date
  103. Dim dExpire As Date
  104. Dim stSystemTime As SYSTEMTIME
  105. Dim lReturnValue As Long
  106.     lReturnValue = FileTimeToSystemTime(ci.LastAccessTime, stSystemTime)
  107.     With stSystemTime
  108.         dExpire = CDate(.wMonth & "/" & .wDay & "/" & .wYear & " " & .wHour & ":" & .wMinute & ":" & .wSecond)
  109.     End With
  110.     CachedEntryLastAccessTime = dExpire
  111. End Property
  112.  
  113. Public Property Get CachedEntryLastModifiedTime() As Date
  114. Dim dExpire As Date
  115. Dim stSystemTime As SYSTEMTIME
  116. Dim lReturnValue As Long
  117.     lReturnValue = FileTimeToSystemTime(ci.LastModifiedTime, stSystemTime)
  118.     With stSystemTime
  119.         dExpire = CDate(.wMonth & "/" & .wDay & "/" & .wYear & " " & .wHour & ":" & .wMinute & ":" & .wSecond)
  120.     End With
  121.     CachedEntryLastModifiedTime = dExpire
  122. End Property
  123.  
  124. Public Property Get CachedEntryLastSyncTime() As Date
  125. Dim dExpire As Date
  126. Dim stSystemTime As SYSTEMTIME
  127. Dim lReturnValue As Long
  128.     lReturnValue = FileTimeToSystemTime(ci.LastSyncTime, stSystemTime)
  129.     With stSystemTime
  130.         dExpire = CDate(.wMonth & "/" & .wDay & "/" & .wYear & " " & .wHour & ":" & .wMinute & ":" & .wSecond)
  131.     End With
  132.     CachedEntryLastSyncTime = dExpire
  133. End Property
  134.  
  135. Public Property Get CachedEntryFileName() As String
  136. Dim strData As String
  137. Dim lReturnValue As Long
  138. Dim iPosition As Long
  139.     strData = String$(lstrlenA(ByVal ci.lpszLocalFileName), 0)
  140.     lReturnValue = lstrcpyA(strData, ci.lpszLocalFileName)
  141.     If lReturnValue Then CachedEntryFileName = strData
  142. End Property
  143.  
  144. Public Property Get CachedEntrySourceURL() As String
  145. Dim strData As String
  146. Dim lReturnValue As Long
  147. Dim iPosition As Long
  148.     strData = String$(lstrlenA(ci.lpszSourceUrlName), 0)
  149.     lReturnValue = lstrcpyA(strData, ci.lpszSourceUrlName)
  150.     If lReturnValue Then CachedEntrySourceURL = strData
  151. End Property
  152.  
  153. Public Function DeleteCacheEntry(SourceUrl As String) As Boolean
  154. Dim lReturnValue As Long
  155.     lReturnValue = DeleteUrlCacheEntry(SourceUrl)
  156.     DeleteCacheEntry = CBool(lReturnValue)
  157. End Function
  158.  
  159. Public Function FindEntryInCache(Url As String) As Boolean
  160. Dim lReturnValue As Long, lSizeOfStruct As Long
  161.     lReturnValue = GetUrlCacheEntryInfo(Url, 0&, lSizeOfStruct)
  162.     If lPtrCI Then LocalFree lPtrCI
  163.     lPtrCI = LocalAlloc(LMEM_FIXED, lSizeOfStruct)
  164.     If lPtrCI Then
  165.         CopyMemory ByVal lPtrCI, lSizeOfStruct, 4
  166.         lReturnValue = GetUrlCacheEntryInfo(Url, lPtrCI, lSizeOfStruct)
  167.         CopyMemory ci, ByVal lPtrCI, Len(ci)
  168.         LocalFree lPtrCI
  169.     End If
  170.     FindEntryInCache = CBool(lReturnValue)
  171. End Function
  172.  
  173. Public Function FindFirstCacheEntry() As Boolean
  174. Dim lSizeOfStruct As Long
  175.     If hEnumHandle <> 0 Then FindCloseUrlCache hEnumHandle
  176.     hEnumHandle = FindFirstUrlCacheEntry(vbNullString, 0&, lSizeOfStruct)
  177.     If lPtrCI Then LocalFree lPtrCI
  178.     lPtrCI = LocalAlloc(LMEM_FIXED, lSizeOfStruct)
  179.     If lPtrCI Then
  180.         CopyMemory ByVal lPtrCI, lSizeOfStruct, 4
  181.         hEnumHandle = FindFirstUrlCacheEntry(ByVal vbNullString, lPtrCI, lSizeOfStruct)
  182.         CopyMemory ci, ByVal lPtrCI, Len(ci)
  183.     End If
  184.     FindFirstCacheEntry = CBool(hEnumHandle)
  185. End Function
  186.  
  187. Public Function FindNextCacheEntry() As Boolean
  188. Dim lReturnValue As Long, lSizeOfStruct As Long
  189.     If hEnumHandle <> 0 Then
  190.         lReturnValue = FindNextUrlCacheEntry(hEnumHandle, 0&, lSizeOfStruct)
  191.         If lPtrCI Then LocalFree lPtrCI
  192.         lPtrCI = LocalAlloc(LMEM_FIXED, lSizeOfStruct)
  193.         If lPtrCI Then
  194.             CopyMemory ByVal lPtrCI, lSizeOfStruct, 4
  195.             lReturnValue = FindNextUrlCacheEntry(hEnumHandle, lPtrCI, lSizeOfStruct)
  196.             CopyMemory ci, ByVal lPtrCI, Len(ci)
  197.         End If
  198.         If lReturnValue <> 0 Then FindNextCacheEntry = CBool(lReturnValue)
  199.     End If
  200. End Function
  201.  
  202. Private Sub Class_Terminate()
  203.     If hEnumHandle Then Call FindCloseUrlCache(hEnumHandle)
  204. End Sub
Еще нашел код, который копирует в буфер сам объект Image. Он у меня на веб-странице такой 1. Фильтром находится правильно. Имеет тип HTMLImg ("[Object HTMLImageElement]") Но при попытке добавления к ControlRange объекта HTMLImg получаю ошибку: "object does not support this property or method".
Листинг программы 
  1. Sub Command1_Click()
  2.  
  3.     Dim sURL As String: sURL = "https://eu.battle.net/account/creation/tos.html?country=RUS"
  4.  
  5.     Dim appIE As Object 'SHDocVw.InternetExplorer
  6.     Set appIE = CreateObject("InternetExplorer.Application")
  7.  
  8.     With appIE
  9.         .Navigate sURL
  10.         .Visible = True
  11.         '.Silent = True
  12.         '.FullScreen = True
  13.  
  14.         Do While (.Busy Or .readyState <> 4): DoEvents: Loop
  15.  
  16.         Dim D As Object 'MSHTML.HTMLDocument
  17.         Set D = .Document
  18.  
  19.     End with
  20.  
  21.     'Dim f As Object
  22.     'Set f = D.getElementById("sec-string") '// input captcha
  23.  
  24.     'D.Forms("creation").All("captchaInput").Value = "captchaDecode"
  25.  
  26.         Dim x, ctrlRange
  27.         
  28.         For Each x In appIE.Document.All
  29.             If UCase(x.tagName) = UCase("IMG") Then
  30.             '    If InStr(1, UCase(x.src), UCase(imgurl), 1) > 0 Then
  31.                     Stop
  32.                     Set ctrlRange = appIE.Document.body.createControlRange()
  33.                     'Debug.Print x.tagName, x.src
  34.                     ctrlRange.Add (x)
  35.                     Clipboard.Clear
  36.                     ctrlRange.execCommand ("Copy")
  37.                     SavePicture Clipboard.GetData, App.Path & "\1.bmp" ' is used to save the picture to your hard drive
  38.                     Picture1.Picture = Clipboard.GetData
  39.                     Stop
  40.                     'Exit For
  41.             '    End If
  42.             End If
  43.         Next
  44.  
  45. end sub

Решение задачи: «Как загрузить изображение с WEB страницы, не используя его URL адрес»

textual
Листинг программы 
  1. using System;
  2. using mshtml;
  3. using System.Collections.Generic;
  4. using System.ComponentModel;
  5. using System.Data;
  6. using System.Drawing;
  7. using System.Text;
  8. using System.Windows.Forms;
  9. using System.Runtime.InteropServices;
  10.  
  11. namespace Battle_net_Download_Captcha_cs
  12. {
  13.     public partial class Form1 : Form
  14.     {
  15.         public Form1()
  16.         {
  17.             InitializeComponent();
  18.         }
  19.  
  20.         [ComImport, InterfaceType((short)1), Guid("3050F669-98B5-11CF-BB82-00AA00BDCE0B")]
  21.         private interface IHTMLElementRenderFixed
  22.         {
  23.             void DrawToDC(IntPtr hdc);
  24.             void SetDocumentPrinter(string bstrPrinterName, IntPtr hdc);
  25.         }
  26.  
  27.  
  28.         void GetImage(string id)
  29.         {
  30.             HtmlDocument D = webBrowser1.Document;
  31.             
  32.             HtmlElement e = D.GetElementById(id);
  33.  
  34.             int i = 0;
  35.  
  36.             MessageBox.Show("Процедура");
  37.  
  38.             //foreach (mshtml.IHTMLImgElement img in webBrowser1.Document.Images)
  39.             //{
  40.             //    MessageBox.Show("Картинка");
  41.  
  42.             HtmlElementCollection collection = D.Images;
  43.             foreach (HtmlElement c in collection)
  44.             {
  45.                 MessageBox.Show(c.Id);
  46.  
  47.                 IHTMLImgElement img = (IHTMLImgElement)c.DomElement; // e.DomElement (for parsed element)
  48.                 IHTMLElementRenderFixed render = (IHTMLElementRenderFixed)img;
  49.  
  50.                 Bitmap bmp = new Bitmap(img.width, img.height);
  51.                 Graphics g = Graphics.FromImage(bmp);
  52.                 IntPtr hdc = g.GetHdc();
  53.                 render.DrawToDC(hdc);
  54.                 g.ReleaseHdc(hdc);
  55.  
  56.                 bmp.Save("C:\\temp\\captcha" + i + ".png");
  57.  
  58.                 MessageBox.Show("Готово");
  59.  
  60.                 i ++;
  61.             }
  62.             //return bmp;
  63.         }
  64.  
  65.  
  66.         private void button1_Click(object sender, EventArgs e)
  67.         {
  68.             webBrowser1.Navigate("https://eu.battle.net/account/creation/tos.html?country=RUS");
  69.         }
  70.  
  71.         private void webBrowser1_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
  72.         {
  73.             if (e.Url.AbsolutePath != (sender as WebBrowser).Url.AbsolutePath)
  74.                 return;
  75.  
  76.             while (webBrowser1.IsBusy || webBrowser1.ReadyState != WebBrowserReadyState.Complete)
  77.             {
  78.                 Application.DoEvents();
  79.                 //System.Threading.Thread.Sleep(100);
  80.             }
  81.  
  82.             //captchaInput
  83.             //Bitmap img = GetImage("sec-string");
  84.  
  85.             GetImage("sec-string");
  86.         }
  87.     }
  88. }

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