I am a newbie to C++. I want to get the content of the clipboard, which might contain Unicode chars, append a div tag with some content formatted in HTML and set that back to clipboard.
I have achieved successfully in getting the content and appending it. But could not set it back to the clipboard as an HTML text. I have achieved setting as simple text. Here is my code:
#include <shlwapi.h>
#include <iostream>
#include <conio.h>
#include <stdio.h>
using namespace std;
wstring getClipboard(){
if (OpenClipboard(NULL)){
HANDLE clip = GetClipboardData(CF_UNICODETEXT);
WCHAR * c;
c = (WCHAR *)clip;
CloseClipboard();
return (WCHAR *)clip;
}
return L"";
}
bool setClipboard(wstring textToclipboard)
{
if (OpenClipboard(NULL)){
EmptyClipboard();
HGLOBAL hClipboardData;
size_t size = (textToclipboard.length()+1) * sizeof(WCHAR);
hClipboardData = GlobalAlloc(NULL, size);
WCHAR* pchData = (WCHAR*)GlobalLock(hClipboardData);
memcpy(pchData, textToclipboard.c_str(), size);
SetClipboardData(CF_UNICODETEXT, hClipboardData);
GlobalUnlock(hClipboardData);
CloseClipboard();
return true;
}
return false;
}
int main (int argc, char * argv[])
{
wstring s = getClipboard();
s += std::wstring(L"some extra text <b>hello</b>");
setClipboard(s);
getch();
return 0;
}
I did try using the code described here and read the doc here. But I couldn't make it work. What I tried could be way off track or completely wrong.
Update: The code below is what I tried after the modifications suggested by Cody Gray to the original code presented here:
bool CopyHTML2(WCHAR *html ){
wchar_t *buf = new wchar_t [400 + wcslen(html)];
if(!buf) return false;
static int cfid = 0;
if(!cfid) cfid = RegisterClipboardFormat("HTML Format");
// Create a template string for the HTML header...
wcscpy(buf,
L"Version:0.9\r\n"
L"StartHTML:00000000\r\n"
L"EndHTML:00000000\r\n"
L"StartFragment:00000000\r\n"
L"EndFragment:00000000\r\n"
L"<html><body>\r\n"
L"<!--StartFragment -->\r\n");
// Append the HTML...
wcscat(buf, html);
wcscat(buf, L"\r\n");
// Finish up the HTML format...
wcscat(buf,
L"<!--EndFragment-->\r\n"
L"</body>\r\n"
L"</html>");
wchar_t *ptr = wcsstr(buf, L"StartHTML");
wsprintfW(ptr+10, L"%08u", wcsstr(buf, L"<html>") - buf);
*(ptr+10+8) = L'\r';
ptr = wcsstr(buf, L"EndHTML");
wsprintfW(ptr+8, L"%08u", wcslen(buf));
*(ptr+8+8) = '\r';
ptr = wcsstr(buf, L"StartFragment");
wsprintfW(ptr+14, L"%08u", wcsstr(buf, L"<!--StartFrag") - buf);
*(ptr+14+8) = '\r';
ptr = wcsstr(buf, L"EndFragment");
wsprintfW(ptr+12, L"%08u", wcsstr(buf, L"<!--EndFrag") - buf);
*(ptr+12+8) = '\r';
// Open the clipboard...
if(OpenClipboard(0)) {
EmptyClipboard();
HGLOBAL hText = GlobalAlloc(GMEM_MOVEABLE |GMEM_DDESHARE, wcslen(buf)+4);
wchar_t *ptr = (wchar_t *)GlobalLock(hText);
wcscpy(ptr, buf);
GlobalUnlock(hText);
SetClipboardData(cfid, hText);
CloseClipboard();
GlobalFree(hText);
}
// Clean up...
delete [] buf;
return true;
}
This code compiles successfully, But I get the following error at SetClipboardData : HEAP[Project1.exe]: Heap block at 007A8530 modified at 007A860A past requested size of d2
Project1.exe has triggered a breakpoint.
Please guide me on how to proceed. I am using Visual Studio Express 2012 on Windows 8. Thanks.
You're mismatching ANSI (narrow) and Unicode (wide) strings.
Unlike the wcscpy function, the w in the wsprintf function doesn't stand for "wide", it stands for "Windows". It is part of the Win32 API, rather than the C runtime library. All of the Win32 API functions that work with strings have two versions, one suffixed with an A that deals with ANSI strings and another suffixed with a W that deals with wide strings. The headers hide all of this from you with macros. I explain all of this in more detail here—recommended reading.
Anyway, the simple fix here is to explicitly call the wide variant of that function, since you're correctly using wide strings everywhere else. Make all the calls to wsprintf look like this:
wchar_t *ptr = wcsstr(buf, L"StartHTML");
wsprintfW(ptr+10, L"%08u", wcsstr(buf, L"<html>") - buf);
*(ptr+10+8) = L'\r';
Alternatively, you could use the swprintf function provided by the C runtime library instead of the Win32 version. This one works just like the wcsstr and wcscpy functions you're using elsewhere. The w in the name means "wide". The documentation for this series of functions is here.
Note also that when you use character or string literals, they also need to be wide characters. You accomplish that by prepending them with an L. You do that some places, but miss doing it others. Make sure that you do it consistently.
The compiler should warn you about all this, though. You just need to make sure you turn your warning level up and don't ignore any of the warnings. Also make sure that both the UNICODE and _UNICODE preprocessor symbols are defined globally for your project. That will ensure that you are always calling the Unicode/wide versions of functions. Although that should be the default for all new projects.
This is the function I came up with the help of Jochen Arndt at codeproject.com. Hope this helps somebody. Here is a complete working code, if you are interested in checking this out.
It still has one problem. That is when pasted to onenote alone, it pastes gibberish after a anchor tag. It does not happen with Word, PowerPoint or Excel. And it does not have this problem for normal English language texts. If you have a solution for this, please do let me know. The problem seems to be with OneNote. Not with the code.
bool setClipboard(LPCWSTR lpszWide){
int nUtf8Size = ::WideCharToMultiByte(CP_UTF8, 0, lpszWide, -1, NULL, 0, NULL, NULL);
if (nUtf8Size < 1) return false;
const int nDescLen = 105;
HGLOBAL hGlobal = ::GlobalAlloc(GMEM_MOVEABLE, nDescLen + nUtf8Size);
if (NULL != hGlobal)
{
bool bErr = false;
LPSTR lpszBuf = static_cast<LPSTR>(::GlobalLock(hGlobal));
LPSTR lpszUtf8 = lpszBuf + nDescLen;
if (::WideCharToMultiByte(CP_UTF8, 0, lpszWide, -1, lpszUtf8, nUtf8Size, NULL, NULL) <= 0)
{
bErr = true;
}
else
{
LPCSTR lpszStartFrag = strstr(lpszUtf8, "<!--StartFragment-->");
LPCSTR lpszEndFrag = strstr(lpszUtf8, "<!--EndFragment-->");
lpszStartFrag += strlen("<!--StartFragment-->") + 2;
int i = _snprintf(
lpszBuf, nDescLen,
"Version:1.0\r\nStartHTML:%010d\r\nEndHTML:%010d\r\nStartFragment:%010d\r\nEndFragment:%010d\r\n",
nDescLen,
nDescLen + nUtf8Size - 1, // offset to next char behind string
nDescLen + static_cast<int>(lpszStartFrag - lpszUtf8),
nDescLen + static_cast<int>(lpszEndFrag - lpszUtf8));
}
::GlobalUnlock(hGlobal);
if (bErr)
{
::GlobalFree(hGlobal);
hGlobal = NULL;
}
// Get clipboard id for HTML format...
static int cfid = 0;
cfid = RegisterClipboardFormat("HTML Format");
// Open the clipboard...
if(OpenClipboard(0)) {
EmptyClipboard();
HGLOBAL hText = GlobalAlloc(GMEM_MOVEABLE |GMEM_DDESHARE, strlen(lpszBuf)+4);
char *ptr = (char *)GlobalLock(hText);
strcpy(ptr, lpszBuf);
GlobalUnlock(hText);
::SetClipboardData(cfid, hText);
CloseClipboard();
GlobalFree(hText);
}
}
return NULL != hGlobal;
}
Your problem comes from the use of wchar_t instead of char in the cited example which makes you wrong on the offset computations.
I would however recommend you avoiding the use of wchar_t for transfering UNICODE text to the clipboard. Indeed, UTF-8 char could coded with a sequence of bytes comprised between 1 and 4 bytes, while wchar_t on Windows is a fixed 2 bytes type.
As explained in the Microsoft doc refered in your email, the content of the clipboard shall be UNICODE, which happens to be the same as ASCII for the characters contained in the header of the clipboard memory.
To transfert UNICODE in the clipboard, you can do it using the standard char C++ functions to prepare the content sent to clipboard (std::string for eg.)
While the cited example works, please find here another code sample using C++ framework that can actually copy UTF-8 chars to the clipboard in HTML format:
void copyHTMLtoClipboard(const std::string& html) {
std::string contextStart("Version:0.9\r\nStartHTML:0000000000\r\nEndHTML:0000000000\r\nStartFragment:0000000000\r\nEndFragment:0000000000\r\n<html><body>\r\n<!--StartFragment -->\r\n");
std::string contextEnd("\r\n<!--EndFragment -->\r\n</body></html>");
std::stringstream aux;
aux << contextStart << html << contextEnd;
std::string res = aux.str();
size_t htmlStart = 105 * sizeof(char);
size_t fragmentStart = 119 * sizeof(char);
size_t htmlEnd = res.size() * sizeof(char);
size_t fragmentEnd = htmlEnd - 35 * sizeof(char);
aux.fill('0');
aux.width(10);
aux.seekp(23);
aux << htmlStart;
aux.seekp(43);
aux.fill('0');
aux.width(10);
aux << htmlEnd;
aux.seekp(69);
aux.fill('0');
aux.width(10);
aux << fragmentStart;
aux.seekp(93);
aux.fill('0');
aux.width(10);
aux << fragmentEnd;
res = aux.str();
HGLOBAL hdst = GlobalAlloc(GMEM_MOVEABLE | GMEM_DDESHARE, htmlEnd + sizeof(char));
LPSTR dst = (LPSTR)GlobalLock(hdst);
memcpy(dst, res.c_str(), htmlEnd);
dst[htmlEnd] = 0;
GlobalUnlock(hdst);
OpenClipboard(NULL);
EmptyClipboard();
SetClipboardData(RegisterClipboardFormat(L"HTML Format"), hdst);
CloseClipboard();
GlobalFree(hdst);
}
Note that this code was compiled defining the macros _UNICODE and UNICODE.
Related
I am trying to get the text of the currently chosen tab in CTabCtrl.
int tabCurSel = currentTabCtrl->GetCurSel();
TCITEM tcItem;
tcItem.mask = TCIF_TEXT;
tcItem.cchTextMax = 256; //Do I need this?
CString tabCurrentCString;
currentTabCtrl->GetItem(tabCurSel, &tcItem);
tabCurrentCString = tcItem.pszText;
CT2A tabCurrentChar(tabCurrentCString);
std::string tabCurrentStr(tabCurrentChar);
return tabCurrentStr;
I clearly have some unnecessary string conversions and currently this returns a "Error reading characters of the string" in
tcItem.pszText;
How can I get the string from the CTabCtrl? I ultimately am trying to get an std::string but the main question is how to get the text from the tab.
tcItem.pszText is pointing to 0. To fill it with text, it has to point to a buffer before a call is made to GetItem:
Documentation for: CTabCtrl::GetItem
pszText
Pointer to a null-terminated string containing the tab text if the
structure contains information about a tab. If the structure is
receiving information, this member specifies the address of the buffer
that receives the tab text.
Example:
TCITEM tcItem { 0 };
tcItem.mask = TCIF_TEXT;
const int len = 256;
tcItem.cchTextMax = len;
TCHAR buf[len] = { 0 };
tcItem.pszText = buf;
currentTabCtrl->GetItem(tabCurSel, &tcItem);
Both tcItem.pszText and buf will point to the same text. Or use CString with CString::GetBuffer()/CString::ReleaseBuffer()
CString tabCurrentCString;
TCITEM tcItem;
tcItem.mask = TCIF_TEXT;
tcItem.cchTextMax = 256;
tcItem.pszText = tabCurrentCString.GetBuffer(tcItem.cchTextMax);
BOOL result = currentTabCtrl->GetItem(tabCurSel, &tcItem);
tabCurrentCString.ReleaseBuffer();
if (result)
MessageBox(tabCurrentCString); //success
It looks like you are using the recommended Unicode settings. Avoid converting UNICODE to ANSI (std::string). This conversion will work for Latin languages, most of the time, but it's not needed. You can use std::wstring if you need to use that in STL, or convert to UTF-8 if you want to send data to internet etc.
std::string str = CW2A(tabCurrentCString, CP_UTF8);
I'm writing an MFC app with C++ in Visual Studio 2012. App connects to a MySQL database and shows every row to a List Box.
Words are in Russian, database encoding is cp1251. I've set the same character set using this code:
if (!mysql_set_character_set(mysql, "cp1251")) {
statusBox.SetWindowText((CString)"CP1251 is set for MYSQL.");
}
But it doesn't help at all.
I display data using this code:
while ((row = mysql_fetch_row(result)) != NULL) {
CString string = (CString)row[1];
listBox.AddString(string);
}
This code also doesn't help:
mysql_query(mysql, "set names cp1251");
Please help. What should I do to display cyrillic correctly?
When crossing system boundaries that use different character encodings you have to convert between them. In this case, the MySQL database uses CP 1251 while Windows (and CString) use UTF-16. The conversion might look like this:
#if !defined(_UNICODE)
#error Unicode configuration required
#endif
CString CPtoUnicode( const char* CPString, UINT CodePage ) {
CString retValue;
// Retrieve required string length
int len = MultiByteToWideChar( CodePage, 0,
CPString, -1,
NULL, 0 );
if ( len == 0 ) {
// Error -> return empty string
return retValue;
}
// Allocate CString's internal buffer
LPWSTR buffer = retValue.GetBuffer( len );
// Do the conversion
MultiByteToWideChar( CodePage, 0,
CPString, -1,
buffer, len );
// Return control of the buffer back to the CString object
retValue.ReleaseBuffer();
return retValue;
}
This should be used as follows:
while ( ( row = mysql_fetch_row( result ) ) != NULL ) {
CString string = CPtoUnicode( row[1], 1251 );
listBox.AddString( string );
}
Alternatively, you could use CStrings built-in conversion support, which requires to set the thread's locale to the source encoding (CP 1251) and use the conversion constructor.
We have some data in a text file which is built into our executable as a custom resource to be read at runtime. The size of this text file is over 7 million characters.
I can successfully search for and locate strings within the resource which appear near the top of the text file, but when attempting to search for terms a few million characters down, strstr returns NULL indicating that the string cannot be found. Is there a limit to the length of a string literal that can be stored in a char* or the amount of data that can be stored in an embedded resource? Code is shown below
char* data = NULL;
HINSTANCE hInst = NULL;
HRSRC hRes = FindResource(hInst, MAKEINTRESOURCE(IDR_TEXT_FILE1), "TESTRESOURCE");
if(NULL != hRes)
{
HGLOBAL hData = LoadResource(hInst, hRes);
if (hData)
{
DWORD dataSize = SizeofResource(hInst, hRes);
data = (char*)LockResource(hData);
}
else
break;
char* pkcSearchResult = strstr(data, "NumListDetails");
if ( pkcSearchResult != NULL )
{
// parse data
}
}
Thanks.
The problem might be the method you use for searching. strstr uses ANSI strings, and will terminate when it encounters a '\0' in the search domain.
You might use something like memstr (one of many implementations can be found here).
Do you get any output from GetLastError(), specifically after calling SizeofResource.
You can also check that dataSize > 0 to ensure an error hasn't occurred.
DWORD dataSize = SizeofResource(hInst, hRes);
if(dataSize > 0)
{
data = (char*)LockResource(hData);
}
else
{
//check error codes
}
MSDN Docs
The problem was null characters in the data which prematurely ended the char* variable. To get around this I just had to read the data into a void pointer then copy it into a dynamically created array.
DWORD dataSize = SizeofResource(hInst, hRes);
void* pvData = LockResource(hData);
char* pcData = new char[dataSize];
memcpy_s(pcData,strlen(pcData),pvData,dataSize);
I have a Java class that returns a unicode string... Java has the correct version of the string but when it comes through a JNI wrapper in the form of a jstring it must be converted over to a C++ or C++/CLI string. Here is some test code I have which actually works on most languages except for the asian char sets. Chinese Simplified & Japanese characters are garbled and I can't figure out why. Here is the code snippet, I don't see anything wrong with either methods of conversion (the if statement checks os as I have two VMs with diff OS's and runs the appropriate conversion method).
String^ JStringToCliString(const jstring string){
String^ converted = gcnew String("");
JNIEnv* envLoc = GetJniEnvHandle();
std::wstring value;
jboolean isCopy;
if(string){
try{
jsize len = env->GetStringLength(string);
if(Environment::OSVersion->Version->Major >= 6) // 6 is post XP/2003
{
TraceLog::Log("Using GetStringChars() for string conversion");
const jchar* raw = envLoc->GetStringChars(string, &isCopy);
// todo add exception handling here for jvm
if (raw != NULL) {
value.assign(raw, raw + len);
converted = gcnew String(value.c_str());
env->ReleaseStringChars(string, raw);
}
}else{
TraceLog::Log("Using GetStringUTFChars() for string conversion.");
const char* raw = envLoc->GetStringUTFChars(string, &isCopy);
if(raw) {
int bufSize = MultiByteToWideChar(CP_UTF8, 0 , raw , -1, NULL , 0 );
wchar_t* wstr = new wchar_t[bufSize];
MultiByteToWideChar( CP_UTF8 , 0 , raw , -1, wstr , bufSize );
String^ val = gcnew String(wstr);
delete[] wstr;
converted = val; // partially working
envLoc->ReleaseStringUTFChars(string, raw);
}
}
}catch(Exception^ ex){
TraceLog::Log(ex->Message);
}
}
return converted;
}
Answer was to enable east asian languages in Windows XP as Win7 + Later work fine. Super easy.... waste of a entire day lol.
Have an annoying problem with my code, probably I am doing something wrong because my Python
implementation is much faster!
C++ implementation problems:
Iterating over "HKEY_CLASSES_ROOT" takes a lot of ram, I assume it's because c++ implementation uses lots of variables. Fixed
It's also slow, much slower than python implantation of the code Fixed
The code even slower when trying to iterate over HKEY_CLASSES_ROOT Fixed
New Questions:
Thanks to Nam Nguyen i understood what causing the leaks in my code, and directly effecting execution time, the code below is the fixed one. how come c++ implementation runs as fast as my python implementation?
C++ implementation:
#include <iostream>
#include <windows.h>
#include <stdio.h>
#include <tchar.h>
#include <string>
using namespace std;
#define MAX_KEY_LENGTH 255
int RecurseOpenRegEx(HKEY hkey, string subKey = "",string search = "nothing", DWORD sum = 0)
{
TCHAR csubKey[MAX_KEY_LENGTH];
DWORD nSubKeys = 0;
DWORD pathLength = MAX_PATH;
TCHAR storeKeyName[MAX_KEY_LENGTH];
DWORD keyLength;
HKEY hKey = hkey; //somehow i need to reassign HKEY, otherwise it won't pass it with the function, this is bigger than me tough...
const char * ccsearch = search.c_str();
const char * ccsubKey;
if (subKey != "")
{
ccsubKey = subKey.c_str();
copy(subKey.begin(), subKey.end(),csubKey); //convert string to TCHAR
}
if (RegOpenKeyEx(hkey, ccsubKey, 0, KEY_READ, &hkey) == ERROR_SUCCESS)
{
if (RegQueryInfoKey(hkey, csubKey, &pathLength, NULL,&nSubKeys, NULL, NULL, NULL, NULL, NULL, NULL, NULL) == ERROR_SUCCESS)
{
sum += nSubKeys;
for (DWORD subKeyIndex = 0; subKeyIndex < nSubKeys; subKeyIndex++)
{
keyLength = MAX_KEY_LENGTH;
if (RegEnumKeyEx(hkey, subKeyIndex, storeKeyName, &keyLength, NULL, NULL, NULL, NULL) == ERROR_SUCCESS)
{
string sKeyName = storeKeyName; //Convert TCHAR to string explicitly
if (subKey != "")
{
sKeyName = subKey + "\\" + sKeyName;
}
sum += RecurseOpenRegEx(hKey, sKeyName);
}
}
}
}
RegCloseKey(hkey); //Now closing the right key
return sum;
}
int main()
{
cout << "sum of all keys: " << RecurseOpenRegEx(HKEY_LOCAL_MACHINE);
return 0;
}
Python implementation:
import winreg
def recurseRegistrySearch(key, keySearch = "",subkey = "", subkeypath = "", x = 0):
key = winreg.OpenKey(key, subkey, 0)
y = winreg.QueryInfoKey(key)[0]
x += y
for items in range(x):
try:
subkey = winreg.EnumKey(key, items)
if ((keySearch.lower() in subkey.lower()) and (keySearch != "")):
print(subkeypath + "\\" + subkey)
x += recurseRegistrySearch(key, keySearch, subkey, subkeypath = subkeypath + "\\" + subkey)
except WindowsError:
pass
return x
print("sum of all keys: {0}".format(recurseRegistrySearch(winreg.HKEY_CLASSES_ROOT)))
There is leak of resource in your code. You open hkey but you close hKey (note the difference in case of k and K).
On a side note, you store the opened registry key into hkey itself. And it happens that hkey is the passed in parameter, shared among all calls to RecurseOpenRegEx. That is why "somehow i need to reassign HKEY".
Basically, what I can advise you now is immediately clean up your code. Bugs like these are hard to spot when your code is a too difficult to read. Once done, I believe you will find it easier to debug/trace.
Probably it's your heavy use of string variables ,which involves a lot of dynamic memory allocations.
Try accepting parameters as LPCTSTR .assign string variables inside the function with those LPCTSTRs and pass parameters with str.c_str().