Develop Reference

GetWindowText hangs on Windows 10

TL;DR: Did GetWindowText win32 api change behavior on windows 10?
I have some code that loops through all windows on the desktop to find a window where the title contains some text.
When this code hits a window named "" with class "URL Moniker Notification Window" it hangs on GetWindowText.
GetWindowText is trying to send a message, my guess is WM_GETTEXT.
This window is part of the exe "SearchUI.exe", the process is suspended and can't process messages.
When reading: https://blogs.msdn.microsoft.com/oldnewthing/20030821-00/?p=42833/
according to rule 2, this should not happen.
This code has been working fine for years. (win 7, 8, 8.1)
So did GetWindowText change behavior in Windows 10?
Update:
The code in question.
public static int HwndGet(string partialTitle, string klassenavn)
{
partialTitle = partialTitle ?? "";
var cTitleTemp = new StringBuilder(255);
var hWndTemp = FindWindowEx((IntPtr)0, (IntPtr)0, null, null);
var nypartialTitle = partialTitle.ToUpper();
while (hWndTemp != (IntPtr)0)
{
GetWindowText(hWndTemp, cTitleTemp, cTitleTemp.Capacity);
string sTitleTemp = cTitleTemp.ToString();
sTitleTemp = sTitleTemp.ToUpper();
if (sTitleTemp.StartsWith(nypartialTitle, StringComparison.CurrentCultureIgnoreCase))
{
var className = new StringBuilder(255);
GetClassName(hWndTemp, className, 255);
//sTitleTemp: " + sTitleTemp + " ClassName: " + ClassName);
if (className.ToString().StartsWith(klassenavn, StringComparison.CurrentCultureIgnoreCase))
{
return (int)hWndTemp;
}
}
hWndTemp = GetWindow(hWndTemp, GwHwndnext);
}
return 0; // does not find the window
}
Stack trace:

The code you are using isn't "safe". There is no guarantee that the order of the windows won't change between calls to FindWindowsEx and GetWindow(GwHwndnext). For this reason there is another API, EnumWindows, that is "safe". You could try with it.
Here there is a sample program (based on the one found here).
public static class WndSearcher
{
public static IntPtr SearchForWindow(string wndclass, string title)
{
var sd = new SearchData { Wndclass = wndclass, Title = title };
EnumWindows(sd.EnumWindowsProc, IntPtr.Zero);
return sd.hWndFound;
}
private class SearchData
{
// You can put any dicks or Doms in here...
public string Wndclass;
public string Title;
public IntPtr hWndFound;
public bool EnumWindowsProc(IntPtr hWnd, IntPtr lParam)
{
// Check classname and title
var sb = new StringBuilder(1024);
int res = GetClassName(hWnd, sb, sb.Capacity);
if (res == 0)
{
throw new Win32Exception();
}
if (sb.ToString().StartsWith(Wndclass, StringComparison.CurrentCultureIgnoreCase))
{
sb.Clear();
res = GetWindowText(hWnd, sb, sb.Capacity);
if (res == 0)
{
int error = Marshal.GetLastWin32Error();
if (error != 0)
{
throw new Win32Exception(error);
}
}
if (sb.ToString().StartsWith(Title, StringComparison.CurrentCultureIgnoreCase))
{
hWndFound = hWnd;
// Found the wnd, halt enumeration
return false;
}
}
return true;
}
}
[return: MarshalAs(UnmanagedType.Bool)]
private delegate bool EnumWindowsProc(IntPtr hWnd, IntPtr lParam);
[DllImport("user32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
private static extern bool EnumWindows(EnumWindowsProc lpEnumFunc, IntPtr lParam);
[DllImport("user32.dll", SetLastError = true, CharSet = CharSet.Auto)]
private static extern int GetClassName(IntPtr hWnd, StringBuilder lpClassName, int nMaxCount);
[DllImport("user32.dll", SetLastError = true, CharSet = CharSet.Auto)]
private static extern int GetWindowText(IntPtr hWnd, StringBuilder lpString, int nMaxCount);
}
and then use it like
IntPtr ptr = WndSearcher.SearchForWindow("classname", "windowname");

SendInput not working after attaching thread input to a target process

I'm making an application that needs to work with the UI of a program which doesn't seem to implement UI Automation elements (Inspect.Exe only shows the main pane and no children).
So I researched about what the best ways to implement the features I need were, and found SendInput(), which apparently is a newer version of keybd_event() and mouse_event().
However, since it requires keyboard focus and since I can't afford to set the target window to foreground (to avoid bothering the user while it runs), I kept searching until I found this answer. I did what Skurmedel said, and joined my application's thread to the target's window thread. But now, even if I SetFocus() to the target and then SendInput(), the target window won't be affected.
My question either is "Why doesn't this work?" or "What am I doing wrong?", but I guess a code example will help sorting this out:
ThreadHandler class
class ThreadHandler
{
#region P/Invoking and constants definition
const uint WM_GETTEXT = 0x000D;
[DllImport("user32.dll")]
static extern IntPtr SetFocus(IntPtr hWnd);
[DllImport("user32.dll")]
private static extern int GetWindowThreadProcessId(IntPtr hWnd, uint lpdwProcessId = 0);
delegate bool EnumThreadDelegate(IntPtr hWnd, IntPtr lParam);
[DllImport("user32.dll")]
static extern bool EnumThreadWindows(int dwThreadId, EnumThreadDelegate lpfn,
IntPtr lParam);
[DllImport("user32.dll")]
static extern bool AttachThreadInput(int idAttach, int idAttachTo, bool fAttach);
[DllImport("kernel32.dll")]
static extern int GetCurrentThreadId();
[DllImport("user32.dll", CharSet = CharSet.Auto)]
static extern IntPtr SendMessage(IntPtr hWnd, UInt32 Msg, int wParam, StringBuilder lParam);
#endregion
public readonly string ProcessName, WindowName;
protected readonly int TargetThreadID, CurrentThreadID;
protected readonly IntPtr TargetWindowHandle;
public ThreadHandler(string processName, string windowName)
{
CurrentThreadID = GetCurrentThreadId();
ProcessName = processName;
WindowName = windowName;
object[] objs = GetWindowThread(processName, windowName);
if (objs == null)
{
throw new ArgumentException("Could not find the specified process/window.");
}
TargetThreadID = (int)objs[0];
TargetWindowHandle = (IntPtr)objs[1];
}
public ThreadHandler(string processName)
{
CurrentThreadID = GetCurrentThreadId();
ProcessName = processName;
var processes = Process.GetProcessesByName(ProcessName);
if (processes.Length == 0)
{
throw new ArgumentException("Could not find the specified process.");
}
var appProc = processes[0];
WindowName = appProc.MainWindowTitle;
TargetThreadID = GetWindowThreadProcessId(appProc.MainWindowHandle);
TargetWindowHandle = appProc.MainWindowHandle;
}
public bool AttachThreadInput()
{
return AttachThreadInput(CurrentThreadID, TargetThreadID, true);
}
public bool DetachThreadInput()
{
return AttachThreadInput(CurrentThreadID, TargetThreadID, false);
}
public void SetFocus()
{
SetFocus(TargetWindowHandle);
}
static object[] GetWindowThread(string processName, string windowName)
{
var processes = Process.GetProcessesByName(processName);
if (processes.Length > 0)
{
//Fill a list of handles
var handles = new List<IntPtr>();
foreach (ProcessThread thread in processes[0].Threads)
EnumThreadWindows(thread.Id,
(hWnd, lParam) => { handles.Add(hWnd); return true; }, IntPtr.Zero);
//Create a stringbuilder to function as storage unit
StringBuilder nameBuffer = new StringBuilder(64);
foreach (var hWnd in handles)
{
//And finally compare the caption of the window with the requested name
nameBuffer.Clear();
SendMessage(hWnd, WM_GETTEXT, nameBuffer.Capacity, nameBuffer);
if (nameBuffer.ToString() == windowName)
{
return new object[2] { GetWindowThreadProcessId(hWnd), hWnd };
}
}
}
return null;
}
}
Main method of the application
static void Main(string[] args)
{
Console.WriteLine("Please input the name of the process to hook: ");
string pName = Console.ReadLine();
Console.WriteLine("Input the name of a specific window, or leave blank: ");
string pWnd = Console.ReadLine();
ThreadHandler threadHandler;
try
{
if(!String.IsNullOrWhiteSpace(pWnd))
threadHandler = new ThreadHandler(pName, pWnd);
else
threadHandler = new ThreadHandler(pName);
}
catch
{
Console.WriteLine("Error: " + pName +" does not seem to be running.");
Console.ReadKey();
return;
}
if (!threadHandler.AttachThreadInput())
{
Console.WriteLine("Error: The application tried to attach its Input Processing Mechanism to " + threadHandler.ProcessName + ", but failed.");
Console.ReadKey();
return;
}
Console.WriteLine("Input Processing Mechanism correctly attached to " + threadHandler.ProcessName + ".");
threadHandler.SetFocus();
InputSimulator.SimulateTextEntry("test"); //InputSimulator is a seemingly famous SendInput wrapper. Replacing this line with the code for a keystroke also doesn't work.
Console.ReadLine();
Console.WriteLine("Detaching Input Processing Mechanism.");
threadHandler.DetachThreadInput();
}
Thanks in advance if you can elucidate me on the arcane arts of SendInput().

Make sure the specific control you are sending the keystrokes to is properly focused.
You should be able to use SetFocus to give focus to the control you are sending the keystrokes to.
SendMessage and PostMessage can also be used to send keystrokes, but it's BAD PRACTICE and should be avoided.
Check out System.Windows.Forms.SendKeys for information on sending keystrokes though the Forms class in .NET.
In a lot of cases, if you don't need the keystrokes themselves, you can just change the text on a window using SendMessage with WM_SETTEXT if this is what you're looking to do.

Detecting if an Internet Explorer process is running Flash Player

Ok, here is a little 1 million dollars question. I'm developing an application that checks if any of your browsers is currently running a Flash application. Here is my core native implementation:
// Using CreateToolhelp32Snapshot allows to list all the modules loaded by a specific process.
internal static Boolean ProcessContainsModule(Process process, String moduleMask)
{
IntPtr snapshotHandle;
if (Environment.Is64BitProcess)
snapshotHandle = CreateToolhelp32Snapshot((SnapshotFlags.Module | SnapshotFlags.Module32), (UInt32)process.Id);
else
snapshotHandle = CreateToolhelp32Snapshot(SnapshotFlags.Module, (UInt32)process.Id);
if (snapshotHandle == IntPtr.Zero)
return false;
Boolean result = false;
ModuleEntry entry = new ModuleEntry();
entry.Size = ModuleEntry.SizeOf;
if (Module32First(snapshotHandle, ref entry))
{
do
{
if (entry.ModuleName.FitsMask(moduleMask))
{
result = true;
break;
}
entry = new ModuleEntry();
entry.Size = ModuleEntry.SizeOf;
}
while (Module32Next(snapshotHandle, ref entry));
}
CloseHandle(snapshotHandle);
return result;
}
// This is a simple wildcard matching implementation.
public static Boolean FitsMask(this String value, String mask)
{
Regex regex;
if (!s_MaskRegexes.TryGetValue(mask, out regex))
s_MaskRegexes[mask] = regex = new Regex(String.Concat('^', Regex.Escape(mask.Replace(".", "__DOT__").Replace("*", "__STAR__").Replace("?", "__QM__")).Replace("__DOT__", "[.]").Replace("__STAR__", ".*").Replace("__QM__", "."), '$'), RegexOptions.IgnoreCase);
return regex.IsMatch(value);
}
Now, Process Explorer was very useful during my processes exploration.
Detecting this with Chrome is very simple:
if ((process.ProcessName == "chrome") && NativeMethods.ProcessContainsModule(process, "PepFlashPlayer.dll"))
Detecthing this with Firefox is also very simple:
if ((process.ProcessName.StartsWith("FlashPlayerPlugin")) && NativeMethods.ProcessContainsModule(process, "NPSWF32*"))
Like always, everything changes when you are looking at Internet Explorer. Any clue about how to detect this with Microsoft's browser?

OK I found it:
if ((process.ProcessName == "iexplore") && NativeMethods.ProcessContainsModule(process, "Flash32*"))

I've modified the code by Zarathos to make it actually compilable, as well as add some personal touches.
tl;dr: This works for Firefox, sometimes for Chrome, not at all for IE
First off, here's the basic code:
using System;
using System.Linq;
using System.Runtime.InteropServices;
using System.Diagnostics;
#region pinvoke.net boilerplate
[Flags]
private enum SnapshotFlags : uint
{
HeapList = 0x00000001,
Process = 0x00000002,
Thread = 0x00000004,
Module = 0x00000008,
Module32 = 0x00000010,
Inherit = 0x80000000,
All = 0x0000001F,
NoHeaps = 0x40000000
}
private struct MODULEENTRY32
{
private const int MAX_PATH = 255;
internal uint dwSize;
internal uint th32ModuleID;
internal uint th32ProcessID;
internal uint GlblcntUsage;
internal uint ProccntUsage;
internal IntPtr modBaseAddr;
internal uint modBaseSize;
internal IntPtr hModule;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = MAX_PATH + 1)]
internal string szModule;
[MarshalAs(UnmanagedType.ByValTStr, SizeConst = MAX_PATH + 5)]
internal string szExePath;
}
[DllImport("kernel32", SetLastError = true, CharSet = System.Runtime.InteropServices.CharSet.Auto)]
static extern IntPtr CreateToolhelp32Snapshot([In]UInt32 dwFlags, [In]UInt32 th32ProcessID);
[DllImport("kernel32", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
private static extern bool CloseHandle([In] IntPtr hObject);
[DllImport("kernel32.dll")]
static extern bool Module32First(IntPtr hSnapshot, ref MODULEENTRY32 lpme);
[DllImport("kernel32.dll")]
static extern bool Module32Next(IntPtr hSnapshot, ref MODULEENTRY32 lpme);
#endregion
static bool ProcessContainsModule(Process process, string searchTerm)
{
bool result = false;
//get handle to process
IntPtr snapshotHandle = Environment.Is64BitProcess ?
CreateToolhelp32Snapshot((UInt32)(SnapshotFlags.Module | SnapshotFlags.Module32), (UInt32)process.Id) :
CreateToolhelp32Snapshot((UInt32)SnapshotFlags.Module, (UInt32)process.Id);
if (snapshotHandle == IntPtr.Zero)
{
return result;
}
//walk the module list
try
{
MODULEENTRY32 entry = new MODULEENTRY32() { dwSize = (uint)Marshal.SizeOf(typeof(MODULEENTRY32)) };
if (Module32First(snapshotHandle, ref entry))
{
do
{
if (entry.szModule.IndexOf(searchTerm, StringComparison.OrdinalIgnoreCase) >= 0)
{
result = true;
break;
}
entry = new MODULEENTRY32() { dwSize = (uint)Marshal.SizeOf(typeof(MODULEENTRY32)) };
}
while (Module32Next(snapshotHandle, ref entry));
}
return result;
}
finally
{
CloseHandle(snapshotHandle);
}
}
You can use it like so:
static bool IsFlashLoadedInFirefox()
{
return Process.GetProcessesByName("plugin-container").Any(x => ProcessContainsModule(x, "NPSWF"));
}
static bool IsFlashLoadedInInternetExplorer()
{
//This doesn't work. For some reason can't get modules from child processes
return Process.GetProcessesByName("iexplore").Any(x => ProcessContainsModule(x, "Flash32"));
}
static bool IsFlashLoadedInChrome()
{
//Doesn't work reliably. See description.
return Process.GetProcessesByName("chrome").Any(x => ProcessContainsModule(x, "pepflashplayer"));
}
As noted in the comments, only Firefox seems to work reliably. In the case of IE (IE11), Module32First() fails for some reason. In the case of Chrome, things get a bit more interesting:
If a new tab is navigated to youtube.com or any YouTube video, the code works
If a new tab is navigated to a play list on YouTube, however, the code fails because pepFlashPlayer.dll isn't in the module list of the process (checked with ProcessExplorer). What's more, if you continue to navigate to other non-playlist YouTube videos, it still doesn't show up.
Note that this approach of checking the loaded DLLs of a process is very fragile, and if any of the browsers decide to change either the DLL they load or how it is loaded then the code breaks.
References:
http://pinvoke.net/default.aspx/kernel32.createtoolhelp32snapshot
http://pinvoke.net/default.aspx/kernel32/Module32First.html
http://pinvoke.net/default.aspx/kernel32/Module32Next.html

Caching and the WebBrowser control in .Net

I'm using the WebBrowser control in .Net to execute some 3rd party affiliate marketing conversions.
I have a queue table in a database with all the scripts/images to execute. I loop through all these in a WinForms app with the WebBrowser control. After I've executed a script/image I Dispose the WebBrowser control, set it to null, and renews it with a new WebBrowser control instance.
Consider this URL: http://renderserver/RenderScript.aspx?id=1
RenderScript.aspx displays an Image with a URL of e.g.: http://3rdparty/img.ashx?id=9343
I use Fiddler to see all requests and responses, and when the same URL is executed twice, it uses some kind of cache. That cache exists underneath the WebBrowser control itself.
This cache means that the img.ashx is not called.
I tried using Internet Explorer to request the URL: http://renderserver/RenderScript.aspx?id=1 and hit F5. Then it is requested perfectly.
But if I click the address bar and hits Enter to navigate to the same URL again - it is not requested. When I use Firefox is will request the page and image everytime no matter if I use F5 or navigate from the address bar.
I found some Win32 API calls (http://support.microsoft.com/kb/326201) that was able to clear the cache. It worked on my local machine. Then the app was deployed to a server running Windows Server 2003 Standard x64 (my own machine is Vista x86).
And now the API calls to clear the cache doesn't work.
Any ideas on why the API calls doesn't work on Windows Server, but works on Vista? Both machines running IE8.

I had the same problem (quite) a while back. Microsoft has a page that was very helpful with this:
http://support.microsoft.com/default.aspx?scid=http://support.microsoft.com:80/support/kb/articles/q326/2/01.asp&NoWebContent=1
I created a class out of Microsoft's sample, however I also had to add a couple if statements to stop processing when there are no more items; it's been a while now, but I'm pretty sure it would throw an error (see ERROR_NO_MORE_ITEMS in the code below).
I hope its helpful!
using System;
using System.Runtime.InteropServices;
// copied from: http://support.microsoft.com/default.aspx?scid=http://support.microsoft.com:80/support/kb/articles/q326/2/01.asp&NoWebContent=1
namespace PowerCode
{
public class IECache
{
// For PInvoke: Contains information about an entry in the Internet cache
[StructLayout(LayoutKind.Explicit, Size = 80)]
public struct INTERNET_CACHE_ENTRY_INFOA
{
[FieldOffset(0)]
public uint dwStructSize;
[FieldOffset(4)]
public IntPtr lpszSourceUrlName;
[FieldOffset(8)]
public IntPtr lpszLocalFileName;
[FieldOffset(12)]
public uint CacheEntryType;
[FieldOffset(16)]
public uint dwUseCount;
[FieldOffset(20)]
public uint dwHitRate;
[FieldOffset(24)]
public uint dwSizeLow;
[FieldOffset(28)]
public uint dwSizeHigh;
[FieldOffset(32)]
public FILETIME LastModifiedTime;
[FieldOffset(40)]
public FILETIME ExpireTime;
[FieldOffset(48)]
public FILETIME LastAccessTime;
[FieldOffset(56)]
public FILETIME LastSyncTime;
[FieldOffset(64)]
public IntPtr lpHeaderInfo;
[FieldOffset(68)]
public uint dwHeaderInfoSize;
[FieldOffset(72)]
public IntPtr lpszFileExtension;
[FieldOffset(76)]
public uint dwReserved;
[FieldOffset(76)]
public uint dwExemptDelta;
}
// For PInvoke: Initiates the enumeration of the cache groups in the Internet cache
[DllImport(#"wininet", SetLastError = true, CharSet = CharSet.Auto, EntryPoint = "FindFirstUrlCacheGroup", CallingConvention = CallingConvention.StdCall)]
public static extern IntPtr FindFirstUrlCacheGroup( int dwFlags, int dwFilter, IntPtr lpSearchCondition, int dwSearchCondition, ref long lpGroupId, IntPtr lpReserved );
// For PInvoke: Retrieves the next cache group in a cache group enumeration
[DllImport(#"wininet", SetLastError = true, CharSet = CharSet.Auto, EntryPoint = "FindNextUrlCacheGroup", CallingConvention = CallingConvention.StdCall)]
public static extern bool FindNextUrlCacheGroup( IntPtr hFind, ref long lpGroupId, IntPtr lpReserved );
// For PInvoke: Releases the specified GROUPID and any associated state in the cache index file
[DllImport(#"wininet", SetLastError = true, CharSet = CharSet.Auto, EntryPoint = "DeleteUrlCacheGroup", CallingConvention = CallingConvention.StdCall)]
public static extern bool DeleteUrlCacheGroup( long GroupId, int dwFlags, IntPtr lpReserved );
// For PInvoke: Begins the enumeration of the Internet cache
[DllImport(#"wininet", SetLastError = true, CharSet = CharSet.Auto, EntryPoint = "FindFirstUrlCacheEntryA", CallingConvention = CallingConvention.StdCall)]
public static extern IntPtr FindFirstUrlCacheEntry( [MarshalAs(UnmanagedType.LPTStr)] string lpszUrlSearchPattern, IntPtr lpFirstCacheEntryInfo, ref int lpdwFirstCacheEntryInfoBufferSize );
// For PInvoke: Retrieves the next entry in the Internet cache
[DllImport(#"wininet", SetLastError = true, CharSet = CharSet.Auto, EntryPoint = "FindNextUrlCacheEntryA", CallingConvention = CallingConvention.StdCall)]
public static extern bool FindNextUrlCacheEntry( IntPtr hFind, IntPtr lpNextCacheEntryInfo, ref int lpdwNextCacheEntryInfoBufferSize );
// For PInvoke: Removes the file that is associated with the source name from the cache, if the file exists
[DllImport(#"wininet", SetLastError = true, CharSet = CharSet.Auto, EntryPoint = "DeleteUrlCacheEntryA", CallingConvention = CallingConvention.StdCall)]
public static extern bool DeleteUrlCacheEntry( IntPtr lpszUrlName );
public static void ClearCache()
{
// Indicates that all of the cache groups in the user's system should be enumerated
const int CACHEGROUP_SEARCH_ALL = 0x0;
// Indicates that all the cache entries that are associated with the cache group
// should be deleted, unless the entry belongs to another cache group.
const int CACHEGROUP_FLAG_FLUSHURL_ONDELETE = 0x2;
// File not found.
const int ERROR_FILE_NOT_FOUND = 0x2;
// No more items have been found.
const int ERROR_NO_MORE_ITEMS = 259;
// Pointer to a GROUPID variable
long groupId = 0;
// Local variables
int cacheEntryInfoBufferSizeInitial = 0;
int cacheEntryInfoBufferSize = 0;
IntPtr cacheEntryInfoBuffer = IntPtr.Zero;
INTERNET_CACHE_ENTRY_INFOA internetCacheEntry;
IntPtr enumHandle = IntPtr.Zero;
bool returnValue = false;
// Delete the groups first.
// Groups may not always exist on the system.
// For more information, visit the following Microsoft Web site:
// http://msdn.microsoft.com/library/?url=/workshop/networking/wininet/overview/cache.asp
// By default, a URL does not belong to any group. Therefore, that cache may become
// empty even when the CacheGroup APIs are not used because the existing URL does not belong to any group.
enumHandle = FindFirstUrlCacheGroup(0, CACHEGROUP_SEARCH_ALL, IntPtr.Zero, 0, ref groupId, IntPtr.Zero);
// If there are no items in the Cache, you are finished.
if (enumHandle != IntPtr.Zero && ERROR_NO_MORE_ITEMS == Marshal.GetLastWin32Error()) {
return;
}
// Loop through Cache Group, and then delete entries.
while (true) {
if (ERROR_NO_MORE_ITEMS == Marshal.GetLastWin32Error() || ERROR_FILE_NOT_FOUND == Marshal.GetLastWin32Error()) {
break;
}
// Delete a particular Cache Group.
returnValue = DeleteUrlCacheGroup(groupId, CACHEGROUP_FLAG_FLUSHURL_ONDELETE, IntPtr.Zero);
if (!returnValue && ERROR_FILE_NOT_FOUND == Marshal.GetLastWin32Error()) {
returnValue = FindNextUrlCacheGroup(enumHandle, ref groupId, IntPtr.Zero);
}
if (!returnValue && (ERROR_NO_MORE_ITEMS == Marshal.GetLastWin32Error() || ERROR_FILE_NOT_FOUND == Marshal.GetLastWin32Error())) {
break;
}
}
// Start to delete URLs that do not belong to any group.
enumHandle = FindFirstUrlCacheEntry(null, IntPtr.Zero, ref cacheEntryInfoBufferSizeInitial);
if (enumHandle != IntPtr.Zero && ERROR_NO_MORE_ITEMS == Marshal.GetLastWin32Error()) {
return;
}
cacheEntryInfoBufferSize = cacheEntryInfoBufferSizeInitial;
cacheEntryInfoBuffer = Marshal.AllocHGlobal(cacheEntryInfoBufferSize);
enumHandle = FindFirstUrlCacheEntry(null, cacheEntryInfoBuffer, ref cacheEntryInfoBufferSizeInitial);
while (true) {
internetCacheEntry = (INTERNET_CACHE_ENTRY_INFOA)Marshal.PtrToStructure(cacheEntryInfoBuffer, typeof(INTERNET_CACHE_ENTRY_INFOA));
if (ERROR_NO_MORE_ITEMS == Marshal.GetLastWin32Error()) {
break;
}
cacheEntryInfoBufferSizeInitial = cacheEntryInfoBufferSize;
returnValue = DeleteUrlCacheEntry(internetCacheEntry.lpszSourceUrlName);
if (!returnValue) {
returnValue = FindNextUrlCacheEntry(enumHandle, cacheEntryInfoBuffer, ref cacheEntryInfoBufferSizeInitial);
}
if (!returnValue && ERROR_NO_MORE_ITEMS == Marshal.GetLastWin32Error()) {
break;
}
if (!returnValue && cacheEntryInfoBufferSizeInitial > cacheEntryInfoBufferSize) {
cacheEntryInfoBufferSize = cacheEntryInfoBufferSizeInitial;
cacheEntryInfoBuffer = Marshal.ReAllocHGlobal(cacheEntryInfoBuffer, (IntPtr)cacheEntryInfoBufferSize);
returnValue = FindNextUrlCacheEntry(enumHandle, cacheEntryInfoBuffer, ref cacheEntryInfoBufferSizeInitial);
}
}
Marshal.FreeHGlobal(cacheEntryInfoBuffer);
}
}
}
To use it in your code, just call:
IECache.ClearCache()
before calling the navigate methods.

Fiddler uses fundamentally the same code as in the KB article to clear the WinINET cache, and I use it on Win2k3 every day.
Rather than wiping the user's entire cache, the proper fix is to set the proper HTTP response header to forbid caching. You can learn more about WinINET caching here: http://www.enhanceie.com/redir/?id=httpperf
(Alternatively, you could simply add a randomized query-string parameter; that way, each time the control encounters a request for the resource, the URL is different and the cache is thus automatically bypassed.)

Try this...
[DllImport("wininet.dll", SetLastError = true)]
private static extern bool InternetSetOption(IntPtr hInternet, int dwOption, IntPtr lpBuffer, int lpdwBufferLength);
private const int INTERNET_OPTION_END_BROWSER_SESSION = 42;
private void clearCache()
{
try
{
Utilities.Web.WebBrowserHelper.WebBrowserHelper.ClearCache();
InternetSetOption(IntPtr.Zero, INTERNET_OPTION_END_BROWSER_SESSION, IntPtr.Zero, 0);
}
catch (Exception exception)
{
//throw;
}
}

That kb article everyone links to has numerous errors in it (where the selected answer's source code came from), and I've wasted ~2 days trying to get it to work in all necessary settings. It is copy pasted across the internet, and there are numerous bugs reported based on OS and IE version.
Fiddler was originally written by a Microsoft employee, and is powered by FiddlerCore.dll. Telerik (the current owners/maintainers/sellers) of Fiddler still update, maintain and give away FiddlerCore for free. If you don't want to add a reference to FiddlerCore, you can disassemble the dll, and it shows the CORRECT way to call all of these horribly documented WinINet functions, but I think posting it here would be a disservice to Telerik / plagarism.
Currently, Fiddlercore is hosted here: http://www.telerik.com/fiddler/fiddlercore

The original code from
https://support.microsoft.com/en-us/kb/326201
seems buggy
checking MSDN documentation and also the VB version here:
https://support.microsoft.com/en-us/kb/262110
I modified the code like this and now for it's working for me (the issue was on execution of FindNextUrlCacheGroup and FindNextUrlCacheEntry):
using System;
using System.Runtime.InteropServices;
namespace Q326201CS
{
// Class for deleting the cache.
public class DeleteIECache
{
// For PInvoke: Contains information about an entry in the Internet cache
[StructLayout(LayoutKind.Explicit, Size=80)]
public struct INTERNET_CACHE_ENTRY_INFOA
{
[FieldOffset(0)] public uint dwStructSize;
[FieldOffset(4)] public IntPtr lpszSourceUrlName;
[FieldOffset(8)] public IntPtr lpszLocalFileName;
[FieldOffset(12)] public uint CacheEntryType;
[FieldOffset(16)] public uint dwUseCount;
[FieldOffset(20)] public uint dwHitRate;
[FieldOffset(24)] public uint dwSizeLow;
[FieldOffset(28)] public uint dwSizeHigh;
[FieldOffset(32)] public FILETIME LastModifiedTime;
[FieldOffset(40)] public FILETIME ExpireTime;
[FieldOffset(48)] public FILETIME LastAccessTime;
[FieldOffset(56)] public FILETIME LastSyncTime;
[FieldOffset(64)] public IntPtr lpHeaderInfo;
[FieldOffset(68)] public uint dwHeaderInfoSize;
[FieldOffset(72)] public IntPtr lpszFileExtension;
[FieldOffset(76)] public uint dwReserved;
[FieldOffset(76)] public uint dwExemptDelta;
}
// For PInvoke: Initiates the enumeration of the cache groups in the Internet cache
[DllImport(#"wininet",
SetLastError=true,
CharSet=CharSet.Auto,
EntryPoint="FindFirstUrlCacheGroup",
CallingConvention=CallingConvention.StdCall)]
public static extern IntPtr FindFirstUrlCacheGroup(
int dwFlags,
int dwFilter,
IntPtr lpSearchCondition,
int dwSearchCondition,
ref long lpGroupId,
IntPtr lpReserved);
// For PInvoke: Retrieves the next cache group in a cache group enumeration
[DllImport(#"wininet",
SetLastError=true,
CharSet=CharSet.Auto,
EntryPoint="FindNextUrlCacheGroup",
CallingConvention=CallingConvention.StdCall)]
public static extern bool FindNextUrlCacheGroup(
IntPtr hFind,
ref long lpGroupId,
IntPtr lpReserved);
// For PInvoke: Releases the specified GROUPID and any associated state in the cache index file
[DllImport(#"wininet",
SetLastError=true,
CharSet=CharSet.Auto,
EntryPoint="DeleteUrlCacheGroup",
CallingConvention=CallingConvention.StdCall)]
public static extern bool DeleteUrlCacheGroup(
long GroupId,
int dwFlags,
IntPtr lpReserved);
// For PInvoke: Begins the enumeration of the Internet cache
[DllImport(#"wininet",
SetLastError=true,
CharSet=CharSet.Auto,
EntryPoint="FindFirstUrlCacheEntryA",
CallingConvention=CallingConvention.StdCall)]
public static extern IntPtr FindFirstUrlCacheEntry(
[MarshalAs(UnmanagedType.LPTStr)] string lpszUrlSearchPattern,
IntPtr lpFirstCacheEntryInfo,
ref int lpdwFirstCacheEntryInfoBufferSize);
// For PInvoke: Retrieves the next entry in the Internet cache
[DllImport(#"wininet",
SetLastError=true,
CharSet=CharSet.Auto,
EntryPoint="FindNextUrlCacheEntryA",
CallingConvention=CallingConvention.StdCall)]
public static extern bool FindNextUrlCacheEntry(
IntPtr hFind,
IntPtr lpNextCacheEntryInfo,
ref int lpdwNextCacheEntryInfoBufferSize);
// For PInvoke: Removes the file that is associated with the source name from the cache, if the file exists
[DllImport(#"wininet",
SetLastError=true,
CharSet=CharSet.Auto,
EntryPoint="DeleteUrlCacheEntryA",
CallingConvention=CallingConvention.StdCall)]
public static extern bool DeleteUrlCacheEntry(
IntPtr lpszUrlName);
public static void doDelete()
{
// Indicates that all of the cache groups in the user's system should be enumerated
const int CACHEGROUP_SEARCH_ALL = 0x0;
// Indicates that all the cache entries that are associated with the cache group
// should be deleted, unless the entry belongs to another cache group.
const int CACHEGROUP_FLAG_FLUSHURL_ONDELETE = 0x2;
// File not found.
const int ERROR_FILE_NOT_FOUND = 0x2;
// No more items have been found.
const int ERROR_NO_MORE_ITEMS = 259;
// Pointer to a GROUPID variable
long groupId = 0;
// Local variables
int cacheEntryInfoBufferSizeInitial = 0;
int cacheEntryInfoBufferSize = 0;
IntPtr cacheEntryInfoBuffer = IntPtr.Zero;
INTERNET_CACHE_ENTRY_INFOA internetCacheEntry;
IntPtr enumHandle = IntPtr.Zero;
bool returnValue = false;
// Delete the groups first.
// Groups may not always exist on the system.
// For more information, visit the following Microsoft Web site:
// http://msdn.microsoft.com/library/?url=/workshop/networking/wininet/overview/cache.asp
// By default, a URL does not belong to any group. Therefore, that cache may become
// empty even when the CacheGroup APIs are not used because the existing URL does not belong to any group.
enumHandle = FindFirstUrlCacheGroup(0, CACHEGROUP_SEARCH_ALL, IntPtr.Zero, 0, ref groupId, IntPtr.Zero);
// If there are no items in the Cache, you are finished.
if (enumHandle != IntPtr.Zero && ERROR_NO_MORE_ITEMS == Marshal.GetLastWin32Error())
return;
// Loop through Cache Group, and then delete entries.
while(true)
{
if (ERROR_NO_MORE_ITEMS == Marshal.GetLastWin32Error() || ERROR_FILE_NOT_FOUND == Marshal.GetLastWin32Error())
{
break;
}
// Delete a particular Cache Group.
returnValue = DeleteUrlCacheGroup(groupId, CACHEGROUP_FLAG_FLUSHURL_ONDELETE, IntPtr.Zero);
//if (returnValue || (!returnValue && ERROR_FILE_NOT_FOUND == Marshal.GetLastWin32Error()))
//{
returnValue = FindNextUrlCacheGroup(enumHandle, ref groupId, IntPtr.Zero);
//}
if (!returnValue && (ERROR_NO_MORE_ITEMS == Marshal.GetLastWin32Error() || ERROR_FILE_NOT_FOUND == Marshal.GetLastWin32Error()))
break;
}
// Start to delete URLs that do not belong to any group.
enumHandle = FindFirstUrlCacheEntry(null, IntPtr.Zero, ref cacheEntryInfoBufferSizeInitial);
if (enumHandle == IntPtr.Zero && ERROR_NO_MORE_ITEMS == Marshal.GetLastWin32Error())
return;
cacheEntryInfoBufferSize = cacheEntryInfoBufferSizeInitial;
cacheEntryInfoBuffer = Marshal.AllocHGlobal(cacheEntryInfoBufferSize);
enumHandle = FindFirstUrlCacheEntry(null, cacheEntryInfoBuffer, ref cacheEntryInfoBufferSizeInitial);
while(true)
{
internetCacheEntry = (INTERNET_CACHE_ENTRY_INFOA)Marshal.PtrToStructure(cacheEntryInfoBuffer, typeof(INTERNET_CACHE_ENTRY_INFOA));
if (ERROR_NO_MORE_ITEMS == Marshal.GetLastWin32Error())
{
break;
}
cacheEntryInfoBufferSizeInitial = cacheEntryInfoBufferSize;
returnValue = DeleteUrlCacheEntry(internetCacheEntry.lpszSourceUrlName);
//if (!returnValue)
//{
returnValue = FindNextUrlCacheEntry(enumHandle, cacheEntryInfoBuffer, ref cacheEntryInfoBufferSizeInitial);
//}
if (!returnValue && ERROR_NO_MORE_ITEMS == Marshal.GetLastWin32Error())
{
break;
}
if (!returnValue && cacheEntryInfoBufferSizeInitial > cacheEntryInfoBufferSize)
{
cacheEntryInfoBufferSize = cacheEntryInfoBufferSizeInitial;
cacheEntryInfoBuffer = Marshal.ReAllocHGlobal(cacheEntryInfoBuffer, (IntPtr) cacheEntryInfoBufferSize);
returnValue = FindNextUrlCacheEntry(enumHandle, cacheEntryInfoBuffer, ref cacheEntryInfoBufferSizeInitial);
}
}
Marshal.FreeHGlobal(cacheEntryInfoBuffer);
}
}
}

This should do the trick:
Response.Cache.SetCacheability(HttpCacheability.NoCache);

Using AttachConsole, user must hit enter to get regular command line

I have a progaram that can be ran both as a winform, or from command line. If it is invoked from a command line I call AttachConsole(-1) to attach to parent console.
However, after my program ends, the user must hit enter to get back the standard command prompt ("c:\>"). is there a way to avoid that need?
Thanks.
I could wrap it in a cmd file to avoid that issue, but I would like to do it from my exe.

Try adding this line just before your exe exits...
System.Windows.Forms.SendKeys.SendWait("{ENTER}");
Bit of a hack, but best I could find when I encountered that problem.

Here is the safest hack that solves the Enter key problem regardless of whether the console window is in the foreground, background, or minimized. You can even run it in multiple console windows.
using System;
using System.Runtime.InteropServices;
using System.Threading;
using System.Windows.Forms;
namespace WindowsAndConsoleApp
{
static class Program
{
const uint WM_CHAR = 0x0102;
const int VK_ENTER = 0x0D;
[DllImport("kernel32.dll")]
static extern bool AttachConsole(int dwProcessId);
private const int ATTACH_PARENT_PROCESS = -1;
[DllImport("kernel32.dll", SetLastError = true)]
static extern bool FreeConsole();
[DllImport("kernel32.dll")]
static extern IntPtr GetConsoleWindow();
[DllImport("user32.dll")]
static extern int SendMessage(IntPtr hWnd, uint msg, IntPtr wParam, IntPtr lParam);
[STAThread]
static void Main(string[] args)
{
if (args.Length > 0)
{
// Do this first.
AttachConsole(ATTACH_PARENT_PROCESS);
Console.Title = "Console Window - Enter Key Test";
Console.WriteLine("Getting the handle of the currently executing console window...");
IntPtr cw = GetConsoleWindow();
Console.WriteLine($"Console handle: {cw.ToInt32()}");
Console.WriteLine("\nPut some windows in from of this one...");
Thread.Sleep(5000);
Console.WriteLine("Take your time...");
Thread.Sleep(5000);
Console.WriteLine("Sending the Enter key now...");
// Send the Enter key to the console window no matter where it is.
SendMessage(cw, WM_CHAR, (IntPtr)VK_ENTER, IntPtr.Zero);
// Do this last.
FreeConsole();
}
else
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new MainForm());
}
}
}
}

Rob L's approach is somewhat dangerous as it will send an Enter to the active window. A better approach is to actual send the Enter to the correct process (console).
here is how
internal static class NativeMethods
{
[DllImport("kernel32.dll", SetLastError = true)]
internal static extern bool AllocConsole();
[DllImport("kernel32.dll", SetLastError = true)]
internal static extern bool FreeConsole();
[DllImport("kernel32", SetLastError = true)]
internal static extern bool AttachConsole(int dwProcessId);
[DllImport("user32.dll")]
internal static extern IntPtr GetForegroundWindow();
[DllImport("user32.dll", SetLastError = true)]
internal static extern uint GetWindowThreadProcessId(IntPtr hWnd, out int lpdwProcessId);
[DllImport("User32.Dll", EntryPoint = "PostMessageA")]
internal static extern bool PostMessage(IntPtr hWnd, uint msg, int wParam, int lParam);
internal const int VK_RETURN = 0x0D;
internal const int WM_KEYDOWN = 0x100;
}
--snip--
bool attached = false;
// Get uppermost window process
IntPtr ptr = NativeMethods.GetForegroundWindow();
int u;
NativeMethods.GetWindowThreadProcessId(ptr, out u);
Process process = Process.GetProcessById(u);
if (string.Compare(process.ProcessName, "cmd", StringComparison.InvariantCultureIgnoreCase) == 0)
{
// attach to the current active console
NativeMethods.AttachConsole(process.Id);
attached = true;
}
else
{
// create new console
NativeMethods.AllocConsole();
}
Console.Write("your output");
NativeMethods.FreeConsole();
if (attached)
{
var hWnd = process.MainWindowHandle;
NativeMethods.PostMessage(hWnd, NativeMethods.WM_KEYDOWN, NativeMethods.VK_RETURN, 0);
}
This solution is build upon the code that is found here:
http://www.jankowskimichal.pl/en/2011/12/wpf-hybrid-application-with-parameters/

It's late to the party and there have been many suggestions over the years, but as I recently just solved this issue myself by stitching together a bunch of information from various posts, I thought I'd post the solution here since it has the most relevant title.
This solution works without using the Enter key or simulating a key press. The only thing I couldn't completely solve is intercepting the Enter from the parent console when your application starts. I think this is impossible because it happens before you get a chance to intercept it; however, there is a reasonable quasi-workaround.
Before diving into the code, here's the sequence of things we need to do:
Attach to the parent console
Capture the text of the current prompt output by the parent console
Clear the parent console's prompt by overwriting it with spaces (not sure it's possible to otherwise prevent this from happening)
Interact with the console as normal
Restore parent console's previous prompt by writing what we captured in #2
This is what it would look like in use:
using System;
using System.Windows.Forms;
public static void Main(string[] args)
{
if (args.Length > 0)
{
using (new ConsoleScope())
{
Console.WriteLine("I now own the console");
Console.WriteLine("MUA HA HA HA HA HA!!!");
}
}
else
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new MainForm());
}
}
... and now for the code. It's more than I'd like, but this is as succinct as I could make it for a post. May this help others attempting the same thing. Enjoy!
using System;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Text;
public sealed class ConsoleScope : IDisposable
{
const int ATTACH_PARENT_PROCESS = -1;
const int STD_OUTPUT_HANDLE = -11;
readonly bool createdNewConsole;
readonly string prompt;
bool disposed;
public ConsoleScope()
{
if (AttachParentConsole())
{
prompt = CaptureParentConsoleCurrentPrompt();
}
else
{
AllocConsole();
createdNewConsole = true;
}
}
~ConsoleScope() => CleanUp();
public void Dispose()
{
CleanUp();
GC.SuppressFinalize(this);
}
static string CaptureParentConsoleCurrentPrompt()
{
var line = (short)Console.CursorTop;
var length = (short)Console.CursorLeft;
var noPrompt = line == 0 && length == 0;
if (noPrompt)
{
return default;
}
return ReadCurrentLineFromParentConsoleBuffer(line, length);
}
static string ReadCurrentLineFromParentConsoleBuffer(short line, short length)
{
var itemSize = Marshal.SizeOf(typeof(CHAR_INFO));
var buffer = Marshal.AllocHGlobal(length * itemSize);
var encoding = Console.OutputEncoding;
var text = new StringBuilder(capacity: length + 1);
var coordinates = default(COORD);
var textRegion = new SMALL_RECT
{
Left = 0,
Top = line,
Right = (short)(length - 1),
Bottom = line,
};
var bufferSize = new COORD
{
X = length,
Y = 1,
};
try
{
if (!ReadConsoleOutput(GetStdOutputHandle(), buffer, bufferSize, coordinates, ref textRegion))
{
Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error());
}
var array = buffer;
for (var i = 0; i < length; i++)
{
var info = Marshal.PtrToStructure<CHAR_INFO>(array);
var chars = encoding.GetChars(info.CharData);
text.Append(chars[0]);
array += itemSize;
}
}
finally
{
Marshal.FreeHGlobal(buffer);
}
// now that we've captured the current prompt, overwrite it with spaces
// so that things start where the parent left off at
Console.SetCursorPosition(0, line);
Console.Write(new string(' ', length));
Console.SetCursorPosition(0, line - 1);
return text.ToString();
}
void CleanUp()
{
if (disposed)
{
return;
}
disposed = true;
RestoreParentConsolePrompt();
if (createdNewConsole)
{
FreeConsole();
}
}
void RestoreParentConsolePrompt()
{
var text = prompt;
if (!string.IsNullOrEmpty(text))
{
// this assumes the last output from your application used
// Console.WriteLine or otherwise output a CRLF. if it didn't,
// you may need to add an extra line here
Console.Write(text);
}
}
[StructLayout(LayoutKind.Sequential)]
struct CHAR_INFO
{
[MarshalAs(UnmanagedType.ByValArray, SizeConst = 2)]
public byte[] CharData;
public short Attributes;
}
[StructLayout(LayoutKind.Sequential)]
struct COORD
{
public short X;
public short Y;
}
[StructLayout(LayoutKind.Sequential)]
struct SMALL_RECT
{
public short Left;
public short Top;
public short Right;
public short Bottom;
}
// REF: https://learn.microsoft.com/en-us/windows/console/allocconsole
[DllImport("kernel32.dll", SetLastError = true)]
static extern bool AllocConsole();
// REF: https://learn.microsoft.com/en-us/windows/console/attachconsole
[DllImport("kernel32.dll", SetLastError = true)]
static extern bool AttachConsole(int dwProcessId);
// REF: https://learn.microsoft.com/en-us/windows/console/freeconsole
[DllImport("kernel32.dll", SetLastError = true)]
static extern bool FreeConsole();
static bool AttachParentConsole() => AttachConsole(ATTACH_PARENT_PROCESS);
// REF: https://learn.microsoft.com/en-us/windows/console/readconsoleoutput
[DllImport("kernel32.dll", SetLastError = true)]
static extern bool ReadConsoleOutput(IntPtr hConsoleOutput, IntPtr lpBuffer, COORD dwBufferSize, COORD dwBufferCoord, ref SMALL_RECT lpReadRegion);
[DllImport("kernel32.dll", SetLastError = true)]
static extern IntPtr GetStdHandle(int nStdHandle);
static IntPtr GetStdOutputHandle() => GetStdHandle(STD_OUTPUT_HANDLE);
}

Ok, I don't have the solution, but it seems to be because the cmd.exe is not waiting on the started process, whereas with a normal console application cmd.exe waits until the the application exits. I don't know what makes cmd.exe decide to wait or not on an application, normal Windows Forms applications are just started and cmd.exe doesn't wait for it to exit. Maybe this hint triggers somebody! I will dig a bit deeper in the mean while.

Try calling the FreeConsole function prior to exiting your executable.

This one has been the easiest solution for me:
myapp.exe [params] | ECHO.

I attempted my own Qt cpp version of Chris Martinez's C# answer:
https://github.com/NightVsKnight/QtGuiConsoleApp/blob/main/QtGuiConsoleApp/main.cpp
#include <QApplication>
#include <QMessageBox>
#ifdef Q_OS_WIN
// Solution posted to https://stackoverflow.com/a/73942013/252308
#define VC_EXTRALEAN
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
QString consolePromptClear()
{
QString prompt = nullptr;
auto bSuccess = AttachConsole(ATTACH_PARENT_PROCESS);
if (bSuccess)
{
auto hStdOut = GetStdHandle(STD_OUTPUT_HANDLE);
if (hStdOut != INVALID_HANDLE_VALUE)
{
CONSOLE_SCREEN_BUFFER_INFO csbi;
bSuccess = GetConsoleScreenBufferInfo(hStdOut, &csbi);
if (bSuccess)
{
auto dwConsoleColumnWidth = (DWORD)(csbi.srWindow.Right - csbi.srWindow.Left + 1);
auto xEnd = csbi.dwCursorPosition.X;
auto yEnd = csbi.dwCursorPosition.Y;
if (xEnd != 0 || yEnd != 0)
{
DWORD dwNumberOfChars;
SHORT yBegin = yEnd;
{
// Walk backwards to find first all blank line
auto pBuffer = (LPWSTR)LocalAlloc(LPTR, dwConsoleColumnWidth * sizeof(WCHAR));
while (yBegin)
{
COORD dwReadCoord = { 0, yBegin };
bSuccess = ReadConsoleOutputCharacterW(hStdOut, pBuffer, dwConsoleColumnWidth, dwReadCoord, &dwNumberOfChars);
if (!bSuccess) break;
DWORD i;
for (i=0; i < dwNumberOfChars; ++i)
{
WCHAR wchar = pBuffer[i];
if (wchar != L' ')
{
--yBegin;
break;
}
}
if (i == dwNumberOfChars)
{
// Found all blank line; we want the *next* [non-blank] line
yBegin++;
break;
}
}
LocalFree(pBuffer);
}
auto promptLength = (yEnd - yBegin) * dwConsoleColumnWidth + xEnd;
auto lpPromptBuffer = (LPWSTR)LocalAlloc(LPTR, promptLength * sizeof(WCHAR));
COORD dwPromptCoord = { 0, yBegin };
bSuccess = ReadConsoleOutputCharacterW(hStdOut, lpPromptBuffer, promptLength, dwPromptCoord, &dwNumberOfChars);
if (bSuccess)
{
Q_ASSERT(promptLength == dwNumberOfChars);
prompt = QString::fromWCharArray(lpPromptBuffer, dwNumberOfChars);
bSuccess = SetConsoleCursorPosition(hStdOut, dwPromptCoord);
if (bSuccess)
{
FillConsoleOutputCharacterW(hStdOut, L' ', promptLength, dwPromptCoord, &dwNumberOfChars);
}
}
LocalFree(lpPromptBuffer);
}
}
}
}
if (prompt.isEmpty())
{
FreeConsole();
return nullptr;
}
else
{
freopen_s((FILE**)stdout, "CONOUT$", "w", stdout);
freopen_s((FILE**)stderr, "CONOUT$", "w", stderr);
freopen_s((FILE**)stdin, "CONIN$", "r", stdin);
return prompt;
}
}
void consolePromptRestore(const QString& prompt)
{
if (prompt.isEmpty()) return;
auto hStdOut = GetStdHandle(STD_OUTPUT_HANDLE);
if (hStdOut == INVALID_HANDLE_VALUE) return;
CONSOLE_SCREEN_BUFFER_INFO csbi;
BOOL bSuccess = GetConsoleScreenBufferInfo(hStdOut, &csbi);
if (!bSuccess) return;
auto xEnd = csbi.dwCursorPosition.X;
auto yEnd = csbi.dwCursorPosition.Y;
if (xEnd == 0 && yEnd == 0) return;
auto buffer = prompt.toStdWString();
auto lpBuffer = buffer.data();
auto nLength = (DWORD)buffer.length();
COORD dwWriteCoord = { 0, (SHORT)(yEnd + 1) };
DWORD dwNumberOfCharsWritten;
WriteConsoleOutputCharacterW(hStdOut, lpBuffer, nLength, dwWriteCoord, &dwNumberOfCharsWritten);
dwWriteCoord = { (SHORT)dwNumberOfCharsWritten, (SHORT)(yEnd + 1) };
SetConsoleCursorPosition(hStdOut, dwWriteCoord);
}
#else
// Non-Windows impl...
#endif
int main(int argc, char *argv[])
{
// NOTE: Any console output before call to consolePromptClear() may get cleared.
// NOTE: Console vs GUI mode has **NOTHING** to do with being passed arguments; You can easily pass arguments to GUI apps.
int returnCode;
auto prompt = consolePromptClear();
if (prompt.isEmpty())
{
QApplication a(argc, argv);
a.setQuitOnLastWindowClosed(true);
QMessageBox msgBox(nullptr);
msgBox.setWindowTitle(a.applicationName());
msgBox.setTextFormat(Qt::RichText);
msgBox.setText("App is detected to be running as a GUI");
msgBox.setStandardButtons(QMessageBox::Ok);
msgBox.show();
returnCode = a.exec();
}
else
{
QCoreApplication a(argc, argv);
QTextStream qout(stdout);
qout << "App is detected to be running as a Console" << Qt::endl;
returnCode = 0;
consolePromptRestore(prompt);
}
return returnCode;
}