How can I avoid duplicated code in this situation?

Question

I built a javascript script that creates dynamic forms, and I'm creating a validation for each section that the user creates, that updates the title from the duplicated questions. So, I built a method for that. The user can choose between creating a section with dropboxes, checkboxes...

So, I had to create 6 methods with exacly the same code, I'm only changing the type of the list. Is there any wait to prevent that, creating a generic method?

    private static int CheckDuplicatedDropdownQuestions(Template template, int i, List<string> collectQuestions)
    {
        foreach (var field in template.Fields.Dropdown)
        {
            if (!collectQuestions.Contains(field.Title))
            {
                collectQuestions.Add(field.Title);
            }
            else
            {
                field.Title = field.Title + " (" + i + ")";
                i++;
            }
        }

        return i;
    }
    ...

Answer 1

Try creating a new method for the foreach part

     private static int CheckDuplicatedDropdownQuestions(Template template, int i, 
    List<string> collectQuestions,string field)
    {
        if(field=="Dropdown")
        {
           NewMethod(template.Fields.Dropdown,ref i);
        }
        else if(field=="CheckBox")
        {
           NewMethod(template.Fields.CheckBox,ref i);
        }

        return i;
    }

    private static void NewMethod(var FieldType,ref int i)
    {
        foreach (var field in FieldType)
        {
            if (!collectQuestions.Contains(field.Title))
            {
                collectQuestions.Add(field.Title);
            }
            else
            {
                field.Title = field.Title + " (" + i + ")";
                i++;
            }
        }
    }