How to change the app. config configuration file

　　

1. Modify appsettings settings

Configuration config = configurationmanager.openexeconfiguration (configurationuserlevel.none);
var seturl = config. appsettings.settings["Apiaddress"];
if (seturl==null)
{
Config. APPSETTINGS.SETTINGS.ADD ("Apiaddress", apihelper.apiurl);;
Config. Save (configurationsavemode.modified);//Saving
Configurationmanager.refreshsection ("appSettings");//refresh (to prevent read-in memory)
}
else if (seturl.value! = Apihelper.apiurl)
{
Config. appsettings.settings["Apiaddress"]. Value = Apihelper.apiurl;
Config. Save (configurationsavemode.modified);
Configurationmanager.refreshsection ("appSettings");
}

2. Modify the connection string for the current project according to the AppConfig of the other project

<summary>
Detects if the config for the API project is changed and updates the current project's config if changed
</summary>
<param name= "connectionStringName" ></param>
<param name= "Newconnectionstring" ></param>
private void Updateconfigdbaddress ()
{
Try
{
var licenseconfig = configurationmanager.openexeconfiguration (Configurationuserlevel.none);
String apipath = Path.Combine (AppDomain.CurrentDomain.BaseDirectory, "... \\Web.config ");
Execonfigurationfilemap map = new Execonfigurationfilemap ();
Map. Execonfigfilename = Apipath;
Configuration apiconfig = configurationmanager.openmappedexeconfiguration (map, Configurationuserlevel.none);

Updateconfigdbaddress (Licenseconfig, Apiconfig, "connectionStringName");
}
Catch
{ }
}

private void Updateconfigdbaddress (Configuration licenseconfig,configuration apiconfig,string connectionstringname)
{
Connectionstringssection apisection = (connectionstringssection) apiconfig.getsection ("connectionStrings");
if (apisection.connectionstrings[connectionstringname]! = NULL)
{
String newvalue = Apisection.connectionstrings[connectionstringname]. ToString ();
Connectionstringssection licensesection = (connectionstringssection) licenseconfig.getsection ("ConnectionStrings") ;
if (licensesection.connectionstrings[connectionstringname] = = null)
{
Connectionstringsettings connectionstringsettings = new Connectionstringsettings (connectionStringName, NewValue);
LICENSESECTION.CONNECTIONSTRINGS.ADD (connectionstringsettings);
Licenseconfig.save (Configurationsavemode.full);
}
else if (newvalue! = Licensesection.connectionstrings[connectionstringname]. ToString ())
{
Licensesection.connectionstrings[connectionstringname]. ConnectionString = newvalue;
Licenseconfig.save (Configurationsavemode.full);
}
}
}

How to change the app. config configuration file