Error while moving connectionString from ADX Portal version 6.0.0017 to Azure Key Vault.

Hi Guys, 

We are moving ConnectionString from web.config in our ADX Studio Portal version 6.0.0017 into Azure Key Vault for security purposes. Our application calls the early bind class of CRM 2013's "xrmservicecontext()" method.

I have tried getting the content using "XrmServiceContext(Microsoft.Xrm.Client.CrmConnection connection)" but we are still getting the error as in the attached screenshot.

Please help us with this. Is there any other alternative approach for this. 

*connectionString format: 

<connectionStrings>

<add name="Xrm" connectionString="ServiceUri=; Domain=; Username=; Password=;"/>

</connectionStrings>

*code used:

String username = "";
String password = "";
String domain = "";
String organizationServiceUrl = "";

var connectionString = "Url={0}; Username={1}; Password={2}; Domain={3};".FormatWith(organizationServiceUrl, username, password, domain);

var context = new XrmServiceContext(new CrmConnection(connectionString));

Thanks in advance.