convert string to sObjectfield type

Question

I have a custom setting where I have fields api name and getting the field api name and use with sObject. At that time I am getting error cannot use string with the sObject. How can I convert the string to a sObjectField or is there any other way to do it. my code

 Map<String, SObjectField> fieldMap = SObjectType.CVSR__Visit__c.fields.getMap();

    for(String fieldName : map_customSet.keyset()){

        system.debug('field map ' + fieldMap.get(fieldName));
        SObjectField sObjfieldName = fieldMap.get(fieldName);

        //system.debug('Visit Field ' + v.sObjfieldName );


    }

Answer 1

You can access SObject fields using Strings (as well as using SObjectField tokens): see the get and put methods listed in the sObject Class documentation.

So generally there is not much benefit in first converting the String to the corresponding SObjectField token. But if you want to do that it is possible via this map for any SObject:

Map<String, SObjectField> m = SObjectType.Account.fields.getMap();

PS

The way that you access fields using strings (or SObjectField tokens) is via get and put:

CVSR__Visit__c v = ...;
String sObjfieldName = 'Name';
String v = (String) a.get(sObjfieldName);

Also note that if this code is running outside of the CVSR managed package and the field is part of the CVSR managed package, you will need to include the "CVSR__" prefix on the field name in your custom setting.