Underlying numeric values in C Sharp (C#) - Step-by-Step Execution

Concept Flow - Underlying numeric values

Define enum with named constants

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Assign enum variable a named constant

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Convert enum to underlying numeric value

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Use numeric value in code or output

This flow shows how an enum variable is assigned a named constant and then converted to its underlying numeric value.

Execution Sample

C Sharp (C#)

enum Color { Red = 1, Green = 2, Blue = 3 }
Color c = Color.Green;
int numericValue = (int)c;
Console.WriteLine(numericValue);

This code defines an enum Color, assigns Green to c, converts it to int, and prints the numeric value.

Execution Table

Step	Action	Variable	Value	Explanation
1	Define enum Color	Color	Red=1, Green=2, Blue=3	Enum named constants assigned numeric values
2	Assign Color.Green to c	c	Green	Variable c holds enum value Green
3	Convert c to int	numericValue	2	Green corresponds to numeric value 2
4	Print numericValue	Output	2	Output shows underlying numeric value of Green

💡 Program ends after printing the numeric value 2

Variable Tracker

Variable	Start	After Step 2	After Step 3	Final
c	undefined	Green	Green	Green
numericValue	undefined	undefined	2	2

Key Moments - 2 Insights

Why do we cast the enum variable to int before printing?

Because enum variables hold named constants, not numbers directly. Casting to int extracts the underlying numeric value, as shown in step 3 of the execution_table.

Can enum values be used directly as numbers without casting?

No, enum values are strongly typed. You must cast them to their underlying numeric type to use them as numbers, as demonstrated in step 3.

Visual Quiz - 3 Questions

Look at the execution_table, what is the value of 'c' after step 2?

A Green

B Red

C Blue

D 2

💡 Hint

Check the 'Variable' and 'Value' columns for step 2 in the execution_table.

At which step is the enum variable converted to its numeric value?

A Step 1

B Step 3

C Step 2

D Step 4

💡 Hint

Look for the step where 'numericValue' is assigned in the execution_table.

If we change Color.Green to have value 5, what will numericValue be after step 3?

A 2

B 3

C 5

D Green

💡 Hint

Refer to variable_tracker and understand that numericValue matches the enum's underlying number.

Concept Snapshot

enum Color { Red=1, Green=2, Blue=3 }
Color c = Color.Green; // c holds named constant
int numericValue = (int)c; // cast to get underlying number
Console.WriteLine(numericValue); // prints 2

Key: Enum values have numeric underlying values; cast to int to use them as numbers.

Full Transcript

This example shows how enums in C# have underlying numeric values. First, we define an enum Color with named constants Red=1, Green=2, Blue=3. Then, we assign the variable c to Color.Green. To get the numeric value of c, we cast it to int, which gives 2. Finally, we print this numeric value. The execution table traces each step, showing how variables change. Beginners often wonder why casting is needed; it's because enums are not numbers directly but named constants. Changing enum values changes the numeric output accordingly.