1. Thanachat Thanomkulabut
Struct
Thanachat Thanomkulabut

2. Array Review Group multiple items of the same type into one "variable"
double[] score;
score = new double[7];
score
Every items is double 1 2 3
How can we do if we want to keep a few things that are of different types together? 4 5 6

3. Structure Preview StudentInfo IcecreamInfo Name: Thanachat Code: C4564
string
string
Dept:
CPE
Flavor:
Chocolate
string
string
Age: 18
Weight:
500 (g)
int
int
Gender: M
Price:
65.50 B
char
double

4. Structure
Allows multiple items of varying types to be kept in one place
Somewhat similar to an array
In C#, a structure is known as struct
A struct is defined by programmer

5. Using struct Type
1. Define struct
2. Create struct
3. Access struct

6. Defining a Struct StudentInfo Name: Thanachat struct StudentInfo {
Must use "struct" keyword
Every struct needs a name
Name:
Thanachat
struct StudentInfo {
public string name;
public string dept;
public int age;
public char gender; }
string
Dept:
CPE
string
Age: 18
int
Members (or properties) of struct
Gender: M
char
Protection level – always use "public" for now

7. Defining a Struct IcecreamInfo struct IcecreamInfo {
public string code;
public string flavor;
public int weight;
public double price; }
Code:
C4564
string
Flavor:
Chocolate
string
Weight:
500 (g)
int
Price:
65.50 B
double

8. Defining a Struct (cont'd)
Where do we put the struct definition?
Inside a class and outside a method
E.g.,
using System;
class StructTest {
static void Main() { : }
struct StdInfo {
public int id;
public string name;
public string dept; }

9. Defining a Struct ComplexNumber Real: 3.7 Imag: -10.5 using System;
class StructTest {
struct ComplexNumber {
public double real;
public double imag; }
static void Main() { :
Real:
3.7
double
Imag:
-10.5
double

10. Defining a Struct (Test I)
MovieInfo
using System;
class StructTest {
struct MovieInfo {
public string name;
public string genre;
public int minute; }
static void Main() { :
Name:
Avatar
string
Genre:
Sci-Fi
string
Minute:
165
int

11. Creating a Struct Or Syntax: <struct_name> <var_name>;
<struct_name> <var_name> = new <struct_name>();
<struct_name> <var_name>;

12. Creating a Struct (Example)
<struct_name> <var_name>= new <struct_name>();
using System;
class StructTest {
static void Main() { }
StudentInfo
struct StdInfo {
public string name;
public string dept;
public int age;
public char gender; }
Name:
string
Dept:
string
Age:
int
StdInfo
student
Gender:
= new
StdInfo ();
char

13. Creating a Struct (Example)
<struct_name> <var_name>;
using System;
class StructTest {
static void Main() { }
StudentInfo
struct StdInfo {
public string name;
public string dept;
public int age;
public char gender; }
Name:
string
Dept:
string
Age:
int
StdInfo
student
StdInfo
Student;
Gender:
= new
StdInfo ();
char

14. Creating a Struct (Test)1
<struct_name> <var_name>= new <struct_name>(); 2
<struct_name> <var_name>;
IcecreamInfo
class StructTest {
static void Main() { }
struct
IcecreamInfo {
Code:
public
string
code;
string
public
string
flavor;
Flavor:
public
int
weight;
string
public
double
price;
Weight: }
int
Price:
IcecreamInfo
ice1
double
IcecreamInfo
ice1;
= new
IcecreamInfo();

15. Accessing Struct Variable
Syntax
<var_name>.<member_name>
Student1
StudentInfo
using System;
class StructTest {
static void Main() { }
Monitor Mc
name
Name: Mc
struct StdInfo {
public string name;
public string dept;
public int age;
public char gender; }
string
dept
Dept:
age 18
string
gender
Age:
int
StdInfo
student1;
student1.name = "Mc";
Gender:
student1.age = 18;
char
Console.Write(student1.name);

16. Accessing Struct Variable
Monitor
z1 + z2 = (7, 4) z1
Real
Imag
ComplexNumber
Real:
Imag:
double 5
class StructExample {
static void Main() { }
struct ComplexNumber {
public double real;
public double imag; } 1 z2
Real
Imag 2
ComplexNumber z1,z2,z3;
z1.real = 5;
z1.imag = 1; 3
z2.real = 2;
z2.imag = 3;
z3.real = z1.real + z2.real; z3
Real
Imag
z3.imag = z1.imag + z2.imag;
Console.Write(("z1 + z2 = ({0}, {1})"
,z3.real,z3.imag); 7 4

17. Test II
From test I extend the Main method to read name, genre and minute of your favorite movie and show them to the monitor
using System;
class StructTest {
struct MovieInfo {
public string name;
public string genre;
public int minute; }
static void Main() { :
MovieInfo
Name:
Genre:
Minute:
string
int

18. Test II static void Main() { MovieInfo myMovie;
myMovie.name = Console.ReadLine();
myMovie.genre = Console.ReadLine();
myMovie.minute = int.Parse(Console.ReadLine());
Console.WriteLine ("Movie name = {0}",myMovie.name);
Console.WriteLine ("Movie genre = {0}",myMovie.genre);
Console.WriteLine ("Movie minute = {0}",myMovie.minute); }

19. Example: Struct & Method
How can I replace this code with Method ReadInfo()
static void Main() {
MovieInfo myMovie;
myMovie.name = Console.ReadLine();
myMovie.genre = Console.ReadLine();
myMovie.minute = int.Parse(Console.ReadLine());
Console.WriteLine ("Movie name = {0}",myMovie.name);
Console.WriteLine ("Movie genre = {0}",myMovie.genre);
Console.WriteLine ("Movie minute = {0}",myMovie.minute); }
static void Main() {
MovieInfo myMovie;
myMovie = ReadInfo(); }
static
MovieInfo
ReadInfo () {
MovieInfo M;
M.name = Console.ReadLine();
M.genre = Console.ReadLine();
M.minute = int.Parse(Console.ReadLine());
return M; }

20. Example: Struct & Method
How can I replace this code with Method ShowInfo()
static void Main() {
MovieInfo myMovie;
myMovie = ReadInfo();
Console.WriteLine ("Movie name = {0}",myMovie.name);
Console.WriteLine ("Movie genre = {0}",myMovie.genre);
Console.WriteLine ("Movie minute = {0}",myMovie.minute); }
ShowInfo(myMovie); }
static
void
ShowInfo
(MovieInfo M) {
Console.WriteLine("Movie name = {0}",M.name);
Console.WriteLine ("Movie genre = {0}",M.genre);
Console.WriteLine ("Movie minute = {0}",M.minute); }

21. Array of Structs 1 2 Array of integers Struct of student info
Array of structs of student info 7 10 3 5 17 8 2 1 4 6 9 11
Aum
CPE
ID:
Name:
Dept:
Aum
CPE
ID:
Name:
Dept:
Nat IE
ID:
Name:
Dept: 1
Top EE
ID:
Name:
Dept: 2

22. Array of Structs Array declaration double[] score;
struct StdInfo {
public int id;
public string name;
public string dept; }
Array declaration
Array of Struct declaration
double[] score;
score = new double[4];
score 1 2 3
StdInfo[] student;
student = new StdInfo[4]; id
name
dept id
name
dept id
name
dept id
name
dept
student 1 2 3

23. Array of Structs Array Accessing score[2] = 5;
Array of Struct Accessing
score[2] = 5;
score 5 1 2 3
student[1].dept = "CPE";
student[3].id = 713; id
name
dept id
name
dept id
name
dept id
name
dept
713
student
CPE 1 2 3

24. Example : Read 50 Student’s Information
class StructTest {
struct StdInfo {
public int id;
public string name;
public string dept; }
static void Main() {
} }
StdInfo
ID:
Name:
Dept:
int
string
StdInfo[] student = new StdInfo[50];
for(int i=0;i<50;i++){
Console.Write("Input ID: ");
student[i].id = int.Parse(Console.ReadLine());
Console.Write("Input Name: ");
student[i].name = Console.ReadLine();
Console.Write("Input Department: ");
student[i].dept = Console.ReadLine(); }

25. Example Display name of students of CPE department
for(int i=0;i<50;i++){
if(student[i].dept == "CPE")
Console.WriteLine(student[i].name); }

26. Any question?