Quick Interview Questions

What is the execution entry point for a C# console application ?

In a C# console application or Windows application, the Main method serves as the entry point of the program. When the application is launched, the Main method is the first method that is invoked by the runtime.

Following are some key details about the Main method:

1. Signature: The Main method must have a specific signature, which is typically defined as static void Main(string[] args). The string[] args parameter allows for command-line arguments to be passed to the application if needed.
2. Static: The Main method must be declared as static. This is because it is called by the runtime before any objects of the class are instantiated.
3. Accessibility: The Main method should not be declared as public. By default, it has the accessibility level of the class it is defined in. Typically, it is declared as private or left with the default accessibility level, which allows it to be accessed within the same class.
4. Return Type: The Main method has a return type of void, indicating that it does not return a value. The application terminates when the Main method completes execution.

Example of a Main method in a console application:

In the above example, the Main method is defined as static within the Program class. It serves as the starting point of the application's execution.

Can we create a console application in c# without Main() method ?

No you can't, All executables in .NET need an entry point.

Every C# application must contain a single Main method specifying where program execution is to begin.

Why Main() method is static ?

A static method can be called without instantiating an object. Therefore main() method needs to be static in order to allow it to be the entry to your program.

What is string[] args in Main method ?

The string[] args parameter in the Main method allows for the inclusion of command-line arguments that can be passed to the program. These arguments can be accessed through the args array, which follows a zero-indexed structure. For instance, args[0] retrieves the first command-line parameter if one is provided.

The Main method can be declared with or without the string[] argument to accommodate the command-line arguments. When working with Visual Studio to develop Windows Forms applications, you have the option to manually add the parameter or utilize the Environment class to retrieve the command-line arguments programmatically.

What is the use of GetCommandLineArgs() method ?

GetCommandLineArgs() returns a string array containing the command-line arguments for the current process. The first element in the array contains the file name of the executing program. The remaining elements contain any additional tokens entered on the command line.

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