(C++ windows) Open default web browser

xDan · Post by **xDan** » Mon Apr 02, 2007 8:08 pm

I know this isn't irrlicht specific but it may be useful to anyone developing a shareware game.

#include <windows.h>
#include <string>

bool runApp(char *appName)
{
    STARTUPINFO sinfo;
    FillMemory(&sinfo, sizeof(STARTUPINFO), 0);
    sinfo.cb = sizeof(STARTUPINFO);

    PROCESS_INFORMATION pinfo;

    if (CreateProcess(NULL, appName, NULL, NULL, FALSE,
        NORMAL_PRIORITY_CLASS, NULL,
        NULL, // current dir
        &sinfo,
        &pinfo)
        )
    {
        CloseHandle(pinfo.hProcess);
        CloseHandle(pinfo.hThread);
        return true;
    }
    return false;
}

void openWebpage(char *page)
{
    // modified from http://www.codeproject.com/internet/urlnewwindow.asp
    
    std::string strBrowser;
    
    HKEY hKey = NULL;
    if (RegOpenKeyEx(HKEY_CLASSES_ROOT, "http\\shell\\open\\command", 0, KEY_READ, &hKey) == ERROR_SUCCESS)
    {
        DWORD cbData = 0;
        if (RegQueryValueEx(hKey, NULL, NULL, NULL, NULL, &cbData) == ERROR_SUCCESS && cbData > 0)
        {
            TCHAR *psz = new TCHAR[cbData];
            if (psz != NULL)
            {
                if (RegQueryValueEx(hKey, NULL, NULL, NULL, (LPBYTE)psz, &cbData) == ERROR_SUCCESS)
                {
                    strBrowser = psz;
                }
                delete [] psz;
            }
        }
        RegCloseKey(hKey);
    }
    
    if (strBrowser.length() > 0)
    {
        std::string::size_type nStart = strBrowser.find('"', 0);
        
        // if first is a quote, then exe path is in quotes, so find the second quote
        if (nStart == 0)
        {
            std::string::size_type nEnd = strBrowser.find('"', 1);
            if (nStart != nEnd && nEnd != std::string::npos)
            {
                strBrowser = strBrowser.substr(nStart+1, nEnd-nStart-1);
            }
        }
        // otherwise if no quotes, 2nd point is the first space after the last backslash
        else
        {
            std::string::size_type nIndex = strBrowser.rfind('\\', strBrowser.length()-1);
            if (nIndex != std::string::npos)
            {
                std::string::size_type nSpace = strBrowser.find(' ', nIndex);
                if (nSpace != std::string::npos)
                {
                    strBrowser = strBrowser.substr(0, nSpace);
                }
            }
        }
        
        std::string command = "\"";
        command += strBrowser;
        command += "\" \"";
        command += page;
        command += "\"";
        
        if (runApp((char *)command.c_str()))
        {
            return;
        }
    }
    
    ShellExecute(NULL, "open", page, NULL, NULL, SW_SHOWNORMAL);
}

To use: openWebpage("http://irrlicht.sourceforge.net");

BlindSide · Post by **BlindSide** » Tue Apr 03, 2007 9:19 am

Wow Im sure "runApp" will be useful too. I noticed in your game you had this and wondered how you did it. Thank you.

kompromis · Post by **kompromis** » Fri Apr 20, 2007 7:29 pm

just using system("url"); is allot easier

white tiger · Post by **white tiger** » Sat Apr 21, 2007 10:48 am

i have winxp, go to the DOS shell, type "url", press enter, but it seem not working. unknow command

Perceval · Post by **Perceval** » Sat Apr 21, 2007 11:54 am

You have to type :
start theUrl

white tiger · Post by **white tiger** » Sun Apr 22, 2007 1:29 pm

work. thanks

xDan · Post by **xDan** » Sun Apr 22, 2007 2:22 pm

kompromis wrote:just using system("url"); is allot easier

Yes, however there are two problems with that:

1) it opens in an existing window (at least with IE)
2) your app hangs while waiting for the browser to load (and sometimes even for the entire life of the new process).

Midnight · Post by **Midnight** » Sun Apr 22, 2007 3:59 pm

xDan wrote:
kompromis wrote:just using system("url"); is allot easier
Yes, however there are two problems with that:

1) it opens in an existing window (at least with IE)
2) your app hangs while waiting for the browser to load (and sometimes even for the entire life of the new process).

1. using console it opens in a new tab with newest IE.
2. so pause your app code manually take the load off or run an app that launches it returns and shutsdown.

xDan · Post by **xDan** » Mon Apr 23, 2007 9:12 pm

using console it opens in a new tab with newest IE.

Oh, well done. It doesn't in some browsers or I wouldn't have bothered posting this.

CuteAlien · Post by **CuteAlien** » Tue May 01, 2007 8:21 pm

I just had to figure that out for a linux system, so i might share also.

Many linux systems have no default browser, but i found a gpl script which i could modify slightly, so that it now starts a browser on most systems. Btw. don't worry about the gpl-license here, the script is an own application so you can still call it from within an application without having to release your own sources.

The script is called "open_browser.sh":

Code: Select all

#!/bin/sh
# Try to find a browser and start it with the parameters given to this script
# Terms of the GNU General Public License apply

HOMEPAGE=$@
BROWSER=`which htmlview`

if [ ! -x "$BROWSER" ]; then
	
	BROWSER=`which firefox`
	if [ ! -x "$BROWSER" ]; then
		
		BROWSER=`which opera`
		if [ ! -x "$BROWSER" ]; then
	
			BROWSER=`which mozilla`
			if [ ! -x "$BROWSER" ]; then
	
				BROWSER=`which konqueror`
				if [ ! -x "$BROWSER" ]; then
	
					BROWSER=`which galeon`
					if [ ! -x "$BROWSER" ]; then

						BROWSER=`which iceweasel`
						if [ ! -x "$BROWSER" ]; then

							BROWSER=`which netscape`
							if [ ! -x "$BROWSER" ]; then
								echo Please start your favorite webbrowser and open:
								echo $@
								exit 1
							fi
						fi
					fi
				fi
			fi
		fi
	fi
fi

$BROWSER $HOMEPAGE &

All i have to do now is to call that script:

Code: Select all

// that code is in the public domain

// you need to set the name used for your script here
#define BROWSER_SCRIPT "open_browser.sh"

void openWebpage(char *page) 
{
    int pid;
    switch ( pid=fork())
    {
        case 0: // child
            execl(BROWSER_SCRIPT, BROWSER_SCRIPT, page, (char*)0);

            // should never be reached
            perror("execl failed");
            exit(2);
        case -1:
            perror("fork failed");
            exit(2);
        default:
            // just continue
            break;
    }
}

Halan · Post by **Halan** » Thu May 24, 2007 4:55 pm

nice, but what files do i need to link?

greets,
halan

Ico · Post by **Ico** » Thu May 24, 2007 6:13 pm

Under Windows I use "ShellExecute" for such things as it allows me to specify the action (lpOperation) to perform too (i.e. for html documents/urls you might try "opennew" instead of just plain "open" - didn't test it on urls however

).

CuteAlien · Post by **CuteAlien** » Thu May 24, 2007 8:00 pm

@Halan: Do you get any linker errors? If you paste them we might be able to tell what you are missing.

@Ico: When you check xDan's code you see that he also uses ShellExecute if everything else fails. I tried also to get along with just using ShellExecute at first, but it had some problems. For example sometimes web pages would be opened in tiny browser windows.

Halan · Post by **Halan** » Fri May 25, 2007 4:06 pm

sry its in german but i think you can read the functions so...

CLauncher.obj : error LNK2019: Verweis auf nicht aufgelöstes externes Symbol "__imp__RegCloseKey@4" in Funktion ""public: void __thiscall CLauncher::openWebpage(char *)" (?openWebpage@CLauncher@@QAEXPAD@Z)".
CLauncher.obj : error LNK2019: Verweis auf nicht aufgelöstes externes Symbol "__imp__RegQueryValueExA@24" in Funktion ""public: void __thiscall CLauncher::openWebpage(char *)" (?openWebpage@CLauncher@@QAEXPAD@Z)".
CLauncher.obj : error LNK2019: Verweis auf nicht aufgelöstes externes Symbol "__imp__RegOpenKeyExA@20" in Funktion ""public: void __thiscall CLauncher::openWebpage(char *)" (?openWebpage@CLauncher@@QAEXPAD@Z)".
..\Bin\Client\ProjectFreedom.exe : fatal error LNK1120: 3 nicht aufgelöste externe Verweise.

greets,
halan

CuteAlien · Post by **CuteAlien** » Fri May 25, 2007 4:37 pm

According to msdn (http://msdn2.microsoft.com/en-us/library/ms724911.aspx) you need Advapi32.lib