asp.net mvc - How to compare two connectingstrings in C# -

i have default connectionstring , connectionstring in webconfig, this:

<add name="bag_zipcodes" connectionstring="password=;persist security info=true;      user id=sa;initial catalog=e;data source=" /> 

but if connectionstring not in webconfig. use one:

configurationmanager.connectionstrings[dbschema.defaultconnectionname]; 

so compare this:

var zipcodeconnection = configurationmanager.connectionstrings["bag_zipcodes"];             //zipcodeconnection = configurationmanager.connectionstrings[dbschema.defaultconnectionname];  if (zipcodeconnection == configurationmanager.connectionstrings["bag_zipcodes"] && zipcodeconnection != null)     zipcodeconnection = configurationmanager.connectionstrings["bag_zipcodes"];  else if (zipcodeconnection == configurationmanager.connectionstrings[dbschema.defaultconnectionname] && zipcodeconnection != null)      zipcodeconnection = configurationmanager.connectionstrings[dbschema.defaultconnectionname]; 

but if delete connectionstring webconfig: add name="bag_zipcodes

then connectionstring null.

thank you

this can done using coalesce statement.

var zipcodeconnection = (configurationmanager.connectionstrings["bag_zipcodes"])                       ?? configurationmanager.connectionstrings[dbschema.defaultconnectionname];