I tried as below mentioned code, for adding field value in dynamic way

String type='Object__c';
Map<String, Schema.SObjectType> schemaMap = Schema.getGlobalDescribe();
//getting required custom object
Schema.SObjectType patentSchema = schemaMap.get(type);
Map<String, Schema.SObjectField> fieldMap = patentSchema.getDescribe().fields.getMap();
Object__c obj = New Object__c();
for (String fieldName : fieldMap.keySet()) 
Schema.SObjectField schemafieldName = fieldMap.get(fieldName);
//It provides to get the object fields label.
String fieldLabel = fieldMap.get(fieldName).getDescribe().getLabel();
//It provides to get the object fields data type.
Schema.DisplayType fielddataType = fieldMap.get(fieldName).getDescribe().getType();
if(fielddataType == Schema.DisplayType.Date)
    //system.debug('Field : '+fieldLabel+' | API Name : '+fieldName+' | DataType : '+fielddataType);
if(fieldLabel == 'Name')
    obj.fieldMap.get(fieldName).getDescribe() = 'Harsha';


When I run this code in developer console I got the error

Error: Expression cannot be assigned


closed as unclear what you're asking by Raul, glls, Oleksandr Berehovskyi, battery.cord, Himanshu Oct 26 '18 at 15:41

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • not absolutely clear for me, what are you trying to achieve ? – Oleksandr Berehovskyi Oct 25 '18 at 11:25
  • Do you want to dynamically add value to any record? – Pranay Jaiswal Oct 25 '18 at 11:29

obj.fieldMap.get(fieldName).getDescribe() = 'Harsha'; is your problem.

Your assignment statements must always have an "lvalue" - something that can receive an assigned value - on the left hand side. You have an expression here, a function call, although an invalid one since obj does not have a property fieldMap.

If what you're trying to do is dynamically assign to a field on your sObject obj, you can use put():

obj.put(fieldName, (Object)'Harsha');

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