Passing value types to methods in C Sharp (C#) - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to pass the integer value to the method.

C Sharp (C#)

int number = 5;
ChangeValue([1]);

void ChangeValue(int num) {
    num = 10;
}
Console.WriteLine(number);

Drag options to blanks, or click blank then click option'

Aref number

Bnumber

Cout number

Din number

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'ref' or 'out' without declaring the method parameter accordingly.

Expecting the original variable to change when passing by value.

Passing number directly passes the value, so changes inside the method do not affect the original variable.

2fill in blank

medium

Complete the method call to pass the integer by reference.

C Sharp (C#)

int value = 3;
ModifyValue([1]);

void ModifyValue(ref int val) {
    val = 7;
}
Console.WriteLine(value);

Drag options to blanks, or click blank then click option'

Aref value

Bin value

Cout value

Dvalue

Attempts:

3 left

💡 Hint

Common Mistakes

Omitting the ref keyword in the method call.

Using out instead of ref when the method expects ref.

Using ref keyword passes the variable by reference, so changes inside the method affect the original variable.

3fill in blank

hard

Fix the error in the method call to correctly pass the value by output parameter.

C Sharp (C#)

int result;
Calculate(out [1]);

void Calculate(out int res) {
    res = 20;
}
Console.WriteLine(result);

Drag options to blanks, or click blank then click option'

Aout result

Bref result

Cresult

Dvalue

Attempts:

3 left

💡 Hint

Common Mistakes

Using ref instead of out in the call.

Not initializing the variable before passing it as out (which is allowed).

The method expects an out parameter, so the call must use out keyword.

4fill in blank

hard

Fill both blanks to correctly pass and modify the value type using ref.

C Sharp (C#)

int count = 1;
UpdateValue([1]);

void UpdateValue([2] int num) {
    num = 100;
}
Console.WriteLine(count);

Drag options to blanks, or click blank then click option'

Aref count

Bcount

Cref

Dout

Attempts:

3 left

💡 Hint

Common Mistakes

Using out keyword in method or call instead of ref.

Passing variable without ref when method expects ref.

The method parameter must have ref keyword, and the call must also use ref to pass by reference.

5fill in blank

hard

Fill all three blanks to create a method that takes a value type by in parameter and call it correctly.

C Sharp (C#)

int data = 50;
DisplayValue([1]);

void DisplayValue([2] int val) {
    Console.WriteLine([3]);
}

Drag options to blanks, or click blank then click option'

Ain data

Bval

Cdata

Din

Attempts:

3 left

💡 Hint

Common Mistakes

Omitting in keyword in method or call.

Trying to modify the parameter inside the method (not allowed with in).

The method parameter uses in keyword to pass by readonly reference, so the call must also use in. Inside the method, print the parameter val.