Getting type information at runtime in C Sharp (C#) - Step-by-Step Execution

Concept Flow - Getting type information at runtime

Start Program

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Create Object

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Call GetType()

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Retrieve Type Info

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Use Type Info (e.g., Name)

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Display or Use Result

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End Program

The program creates an object, calls GetType() to get its type info, then uses that info to display or decide something.

Execution Sample

C Sharp (C#)

string name = "Hello";
Type t = name.GetType();
Console.WriteLine(t.Name);

This code gets the type of the string variable and prints its type name.

Execution Table

Step	Action	Variable/Expression	Result/Value	Output
1	Create string variable	name	"Hello"
2	Call GetType() on name	name.GetType()	System.String (Type object)
3	Assign Type object to t	t	System.String (Type object)
4	Access t.Name property	t.Name	"String"
5	Print t.Name	Console.WriteLine(t.Name)		String

💡 Program ends after printing the type name of the variable.

Variable Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	After Step 4	Final
name	null	"Hello"	"Hello"	"Hello"	"Hello"	"Hello"
t	null	null	System.String (Type object)	System.String (Type object)	System.String (Type object)	System.String (Type object)
t.Name	null	null	null	"String"	"String"	"String"

Key Moments - 3 Insights

Why do we call GetType() on the variable instead of the type name directly?

GetType() is called on the object instance (see Step 2) to get its runtime type. Calling it on the type name itself is not valid because GetType() is an instance method.

What does the Type object represent?

The Type object (assigned to t in Step 3) holds metadata about the variable's type, like its name, methods, properties, etc.

Why does Console.WriteLine(t.Name) print "String"?

Because t.Name accesses the Name property of the Type object, which returns the simple name of the type, here "String" (Step 5).

Visual Quiz - 3 Questions

Look at the execution table, what is the value of variable 't' after Step 3?

A "Hello"

B null

C System.String (Type object)

D "String"

💡 Hint

Check the 'Result/Value' column for Step 3 in the execution_table.

At which step does the program output the type name?

A Step 5

B Step 3

C Step 2

D Step 4

💡 Hint

Look at the 'Output' column in the execution_table to find when output occurs.

If we changed 'name' to an integer variable, what would t.Name be after Step 4?

A "String"

B "Int32"

C "Object"

D "Integer"

💡 Hint

The Type.Name returns the simple type name of the variable's runtime type (see variable_tracker for t.Name).

Concept Snapshot

Use GetType() on an object to get its runtime type info.
The returned Type object has properties like Name to identify the type.
Example: string s = "Hi"; Type t = s.GetType(); t.Name is "String".
GetType() is an instance method, so call it on variables, not type names.
Useful for checking or displaying type info during program execution.

Full Transcript

This example shows how to get type information at runtime in C#. We start by creating a string variable named 'name' with the value "Hello". Then we call the GetType() method on 'name' to get its type information, which returns a Type object representing System.String. We store this Type object in the variable 't'. Next, we access the Name property of 't' to get the simple name of the type, which is "String". Finally, we print this name to the console. This process helps us find out what type a variable is while the program is running.