How reflection bypasses compile-time safety in C Sharp (C#) - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to get the type of the class using reflection.

C Sharp (C#)

Type type = typeof([1]);

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AGetType()

Bclass

CMyClass

Dobject

Attempts:

3 left

💡 Hint

Common Mistakes

Using GetType() inside typeof, which is invalid syntax.

Using 'class' keyword instead of a class name.

Using typeof(MyClass) gets the Type object for the class MyClass.

2fill in blank

medium

Complete the code to get the MethodInfo object for the method named "Calculate".

C Sharp (C#)

MethodInfo method = type.GetMethod([1]);

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ACalculate()

B"Calculate"

CCalculate

DmethodName

Attempts:

3 left

💡 Hint

Common Mistakes

Passing the method name without quotes.

Including parentheses in the method name string.

The method name must be passed as a string, so use "Calculate".

3fill in blank

hard

Fix the error in invoking the method using reflection.

C Sharp (C#)

object result = method.Invoke([1], null);

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Anull

Btype

Cmethod

Dthis

Attempts:

3 left

💡 Hint

Common Mistakes

Passing null for instance methods causes runtime errors.

Passing the Type object instead of an instance.

When invoking an instance method, you must pass the instance object (here this) as the first argument.

4fill in blank

hard

Fill both blanks to create a dictionary of method names and their return types using reflection.

C Sharp (C#)

var methods = type.GetMethods();
var dict = new Dictionary<string, Type> { { [1], [2] } };

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Amethods[0].Name

Bmethods[0].ReturnType

Cmethods[1].Name

Dmethods[1].ReturnType

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing method indices for key and value.

Using method names for both key and value.

Use methods[0].Name as the key and methods[0].ReturnType as the value for the dictionary entry.

5fill in blank

hard

Fill all three blanks to filter methods with no parameters and create a dictionary of their names and return types.

C Sharp (C#)

var filtered = methods.Where(m => m.GetParameters().Length [1] 0);
var dict = filtered.ToDictionary(m => m.[2], m => m.[3]);

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A==

BName

CReturnType

DLength

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect comparison operators like > or <.

Using Length property instead of Name or ReturnType.

Use == to check for zero parameters, then use Name and ReturnType to create the dictionary.