TCS DOT NET Developer Interview Questions and Answers

web.config is specific to a web application and overrides settings in Machine.config

• web.config is specific to a web application, while Machine.config is at the machine level

• web.config can override settings in Machine.config for a specific application

• Machine.config is located in the .NET framework folder, while web.config is in the application folder

State management in .NET refers to the process of storing and retrieving data during the lifecycle of an application.

• State management can be achieved using various techniques such as session state, view state, cookies, and query strings.

• Session state allows storing user-specific data across multiple pages during a user session.

• View state stores the state of the page and its controls between postbacks.

• Cookies can be use...read more

To find the second highest salary, use SQL queries with subqueries or the DISTINCT keyword for unique values.

• Using Subquery: SELECT MAX(salary) FROM employee WHERE salary < (SELECT MAX(salary) FROM employee);

• Using DISTINCT: SELECT DISTINCT salary FROM employee ORDER BY salary DESC LIMIT 1 OFFSET 1;

• Handles Ties: Both methods consider ties, ensuring the second highest unique salary is returned.

• Performance: The choice ...read more

To update the value of 5 to HR in the employee details table, use the SQL UPDATE statement with the appropriate conditions.

• SQL UPDATE Statement: The basic syntax is 'UPDATE table_name SET column_name = new_value WHERE condition;'.

• Example: To update the 'department' column to 'HR' for employees with an ID of 5, the query would be: 'UPDATE employee_details SET department = 'HR' WHERE employee_id = 5;'.

• WHERE Clause: It's ...read more

Solid Principles are a set of five design principles for writing clean, maintainable, and scalable code.

• Single Responsibility Principle (SRP) - A class should have only one reason to change.

• Open/Closed Principle (OCP) - Classes should be open for extension but closed for modification.

• Liskov Substitution Principle (LSP) - Objects of a superclass should be replaceable with objects of its subclasses without affecting the ...read more

Dependency Injection is a design pattern where dependencies are injected into a class rather than created within the class.

• Dependency Injection helps in achieving loose coupling between classes.

• It allows for easier testing by enabling mocking of dependencies.

• There are different ways to implement Dependency Injection such as constructor injection, property injection, and method injection.

• Popular DI containers/frameworks...read more

Configuration settings can be stored in various places such as appsettings.json, environment variables, database, or Azure Key Vault.

• appsettings.json file in ASP.NET Core projects

• Environment variables for sensitive data

• Database for dynamic configuration

• Azure Key Vault for secure storage

To reverse a string, iterate through the characters in the string and build a new string in reverse order.

• Create a new empty string to store the reversed string

• Iterate through the characters of the original string from the end to the beginning

• Append each character to the new string

• Return the reversed string

Routing in .NET MVC is the process of mapping URLs to controller actions.

• Routing is defined in the RouteConfig.cs file in the App_Start folder.

• Routes are defined using the MapRoute method, which takes parameters like URL pattern, default values, and constraints.

• Routes are matched in the order they are defined, so the most specific routes should be placed at the top.

• Route parameters are passed to controller actions as m...read more