Regarding .config files

[MattTC]

Hï!
If the "AddrColWidths" entry is missing in the config file my last code line throws an exception. Is there a common way to check if the entry exists before trying to read it?

I also wonder if there is an easy way to check wether the .config file exists, for example through the config object. I cant find such a way.

String ^exePath = Reflection::Assembly::GetExecutingAssembly()->Location;
System::Configuration::Configuration ^config =  
                                ConfigurationManager::OpenExeConfiguration(exePath);
AppSettingsSection ^appSettingsSection =
                                (AppSettingsSection^)config->GetSection("appSettings");
CommaDelimitedStringCollectionConverter^ converter = 
                                gcnew CommaDelimitedStringCollectionConverter();
CommaDelimitedStringCollection^ collection =
(CommaDelimitedStringCollection^)converter->ConvertFrom(appSettingsSection->Settings["AddrColWidths"]->Value);

Best regards
Mattias

[memeloo]

from my experience I'd discourage you from using .config files. I have always had problems with lost settings in a new app version etc. now I use the windows registry and all problems are gone. (I was to lazy to write my own config wrapper so using the registry was easier but the default .net .config files are evil)

[MattTC]

Well, maybe you´re right, but still, is there an answer to my questions?

[memeloo]

I think the best way is to catch the ConfigurationErrorsException like in msdn examples. some config wrapper could be very useful.

[darwen]

You can check for nulls :

System::Configuration::Configuration ^config =  
    ConfigurationManager::OpenExeConfiguration(exePath);
                                
if (config != nullptr)
{                                
    AppSettingsSection ^appSettingsSection =
        (AppSettingsSection^)config->GetSection("appSettings");
        
    if (appSettingsSection != nullptr)
    {
        if (appSettingsSection->Settings["AddrColWidths"] != nullptr)
        {        
            CommaDelimitedStringCollectionConverter^ converter = 
                gcnew CommaDelimitedStringCollectionConverter();
        
            CommaDelimitedStringCollection^ collection =
                (CommaDelimitedStringCollection^)converter->ConvertFrom(appSettingsSection->Settings["AddrColWidths"]->Value);
        }
    }
}

Darwen.