asp.net core survey application

Building a survey application in ASP.NET Core requires a flexible data model and a modular architecture to accommodate dynamic question types (e.g., multiple choice, free text, rating scales) and user responses.

1. Core Domain Models & Entity Framework Core To support dynamic questionnaires, the domain schema relies on parent-child relationships between surveys, questions, options, and responses. Survey Id (Guid / int): Primary key. Title (string): Survey name. Description (string): Intro text for participants. IsActive (bool): Publishing state. CreatedAt / ExpiresAt (DateTime): Scheduling attributes. Questions (ICollection): List of associated questions. Question Id (Guid / int): Primary key. SurveyId (Guid / int): Foreign key to Survey. Text (string): Question prompt. QuestionType (enum): SingleChoice, MultipleChoice, Text, Rating, Dropdown. IsRequired (bool): Validation rule. Order (int): Display order on the UI. Options (ICollection): Predefined choices (if applicable). QuestionOption Id (Guid / int): Primary key. QuestionId (Guid / int): Foreign key to Question. OptionText (string): Display text for choices. Order (int): Ordering of choices. SurveyResponse Id (Guid / int): Primary key. SurveyId (Guid / int): Foreign key to Survey. RespondentUserId (string / optional): Linked to identity if authenticated, null for anonymous. SubmittedAt (DateTime): Submission timestamp. Answers (ICollection): Individual question responses. Answer Id (Guid / int): Primary key. SurveyResponseId (Guid / int): Foreign key to SurveyResponse. QuestionId (Guid / int): Foreign key to Question. SelectedOptionId (Guid / int, optional): Foreign key for choice-based questions. AnswerText (string, optional): Freeform text answer.
2. Recommended Application Architecture A Clean Architecture or N-Tier Architecture separates business rules, persistence, and presentation concerns. Core / Domain Layer: Contains C# POCO entities, custom domain exceptions, and domain interfaces. Application Layer: Contains business logic, DTOs (Data Transfer Objects), CQRS Handlers (via MediatR), or Service classes (e.g., ISurveyService, IResponseService). Infrastructure Layer: Holds the ApplicationDbContext (EF Core), database migrations, repository implementations, and external integrations (e.g., email notification service). Presentation Layer: ASP.NET Core Web API: Exposes RESTful JSON endpoints for single-page application (SPA) frontends like React, Angular, or Vue.js. ASP.NET Core Blazor / Razor Pages: Server-side or WebAssembly full-stack C# implementation for form building and submission.
3. Key Feature Modules Survey Creator / Builder Module (Admin Side) Dynamic form generator allowing drag-and-drop or sequential reordering of questions. Validation rules setup (min/max length, required fields). Survey publishing controls and unique shareable link generation. Survey Runner Module (Public / Participant Side) Dynamic form rendering driven by ViewModel mappings based on QuestionType. Client-side validation using Data Annotations or FluentValidation alongside client JS/Blazor validation. State preservation to allow multi-page surveys or save-and-resume support. Analytics & Reporting Module Aggregated statistical visualizations for closed-ended questions (pie charts, bar graphs). Data export functionality (CSV, Excel via ClosedXML, or PDF). Real-time submission dashboard using SignalR.
4. Security & Authentication Features Authentication: Managed via ASP.NET Core Identity for administrator accounts and option for anonymous participant submissions. Authorization: Role-based or policy-based access control ([Authorize(Roles = "Admin")]) ensuring survey modification rights remain protected. Submission Protection: CSRF anti-forgery token validation ([ValidateAntiForgeryToken]) and rate limiting middleware to prevent bot submissions.