Auto-implemented properties in C Sharp (C#) - Step-by-Step Execution

Concept Flow - Auto-implemented properties

Define class with auto-property

↓

Compiler creates hidden field

↓

Get or set property value

↓

Use property in code

↓

Property returns or updates hidden field

Auto-implemented properties let you quickly create properties without writing explicit backing fields. The compiler handles the hidden storage.

Execution Sample

C Sharp (C#)

public class Person {
  public string Name { get; set; }
}

Person p = new Person();
p.Name = "Alice";
Console.WriteLine(p.Name);

This code creates a Person with an auto-property Name, sets it to "Alice", then prints it.

Execution Table

Step	Action	Property 'Name' Value	Hidden Field Value	Output
1	Create Person object p	null	null
2	Set p.Name = "Alice"	"Alice"	"Alice"
3	Read p.Name	"Alice"	"Alice"	"Alice" printed
4	End of program	"Alice"	"Alice"	Program ends

💡 Program ends after printing the property value.

Variable Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	Final
p.Name	null	null	"Alice"	"Alice"	"Alice"
Hidden field backing Name	null	null	"Alice"	"Alice"	"Alice"

Key Moments - 3 Insights

Why don't we see a field declared for 'Name' in the code?

Because the compiler automatically creates a hidden field to store the value, as shown by the 'Hidden Field Value' column in the execution_table.

What happens when we set p.Name = "Alice"?

The set accessor stores "Alice" in the hidden field, updating both 'Property Name Value' and 'Hidden Field Value' in the execution_table at step 2.

How does reading p.Name return the correct value?

The get accessor returns the value stored in the hidden field, which is "Alice" at step 3 in the execution_table.

Visual Quiz - 3 Questions

Look at the execution_table, what is the value of the hidden field after step 2?

A null

B "Alice"

C "Bob"

D Empty string

💡 Hint

Check the 'Hidden Field Value' column at step 2 in the execution_table.

At which step does the property 'Name' get assigned a value?

A Step 2

B Step 3

C Step 1

D Step 4

💡 Hint

Look at the 'Action' column in the execution_table to find when p.Name is set.

If we never set p.Name, what would be the output when reading it?

A Empty string

B "Alice"

C null

D Compilation error

💡 Hint

Refer to the 'Property Name Value' at step 1 before any assignment in the variable_tracker.

Concept Snapshot

Auto-implemented properties:
- Syntax: public Type PropertyName { get; set; }
- Compiler creates hidden field automatically
- Simplifies property declaration
- Get returns hidden field value
- Set updates hidden field value

Full Transcript

Auto-implemented properties in C# let you create properties without writing a backing field. The compiler makes a hidden field behind the scenes. When you set the property, it stores the value in this hidden field. When you get the property, it returns the value from the hidden field. In the example, we create a Person class with a Name property. We set p.Name to "Alice" and then print it. The execution table shows the hidden field storing "Alice" after the set operation. This makes code shorter and easier to read while keeping full property functionality.