StringBuilder methods and performance in C Sharp (C#) - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to append a string to the StringBuilder.

C Sharp (C#)

var sb = new StringBuilder();
sb.[1]("Hello");
Console.WriteLine(sb.ToString());

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

AAdd

BInsert

CConcat

DAppend

Attempts:

3 left

💡 Hint

Common Mistakes

Using Add which does not exist for StringBuilder.

Using Concat which is a string method, not StringBuilder.

Using Insert which adds text at a specific position, not at the end.

The Append method adds the specified string to the end of the StringBuilder.

2fill in blank

medium

Complete the code to insert a string at the beginning of the StringBuilder.

C Sharp (C#)

var sb = new StringBuilder("World");
sb.[1](0, "Hello ");
Console.WriteLine(sb.ToString());

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

AInsert

BAppend

CReplace

DRemove

Attempts:

3 left

💡 Hint

Common Mistakes

Using Append which adds text only at the end.

Using Replace which changes existing text.

Using Remove which deletes text.

The Insert method inserts a string at the specified index, here at position 0 (the start).

3fill in blank

hard

Fix the error in the code to remove 5 characters starting at index 6.

C Sharp (C#)

var sb = new StringBuilder("Hello, World!");
sb.[1](6, 5);
Console.WriteLine(sb.ToString());

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

ADelete

BRemove

CCut

DErase

Attempts:

3 left

💡 Hint

Common Mistakes

Using Delete which does not exist in StringBuilder.

Using Cut or Erase which are not valid methods.

The Remove method deletes a specified number of characters starting at a given index.

4fill in blank

hard

Fill both blanks to replace 'World' with 'C#' in the StringBuilder.

C Sharp (C#)

var sb = new StringBuilder("Hello, World!");
sb.[1]("World", [2]);
Console.WriteLine(sb.ToString());

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

A"C#"

BReplace

C"Java"

DRemove

Attempts:

3 left

💡 Hint

Common Mistakes

Using Remove which deletes text but does not replace.

Swapping the order of method and replacement string.

The Replace method replaces all occurrences of a string with another string. Here, 'World' is replaced with 'C#'.

5fill in blank

hard

Fill all three blanks to create a StringBuilder, append 'Hello', insert 'C# ', and remove 1 character at index 5.

C Sharp (C#)

var sb = new [1]();
sb.[2]("Hello");
sb.[3](0, "C# ");
sb.Remove(5, 1);
Console.WriteLine(sb.ToString());

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

AStringBuilder

BAppend

CInsert

DString

Attempts:

3 left

💡 Hint

Common Mistakes

Using String instead of StringBuilder for the object.

Mixing up Append and Insert methods.

First, create a StringBuilder object. Then Append adds 'Hello' at the end. Next, Insert adds 'C# ' at the start. Finally, Remove deletes one character at index 5.