static void Main()
{
Japanese aki = new Japanese();
aki.SayHi();
American tom = new American();
tom.SayHi();
}
static void Main()
{
Japanese jap = new Japanese();
jap.SayHi();
American ap = new American();
ap.SayHi();
}
//↑と同義
// static void SayHelloFromDeligater() {
// Console.WriteLine("hi!");
// }
////////////////////
//
////////////////////
static void Main()
{
//変数
string msg = "Hello World";
Console.WriteLine(msg);
//定数
const string CONST_MSG = "CONST MESSAGE";
Console.WriteLine(CONST_MSG);
//==============================
// 型
//==============================
// 文字列、文字
// string, char
string s = "hello";
char c = 'a';
// 整数値
// byte, short, int, long
int i1 = 100;
// 浮動小数点数
// float, double
double d = 52342.34;
float f = 23.3f;
// 論理値
// bool -> true, false
bool flag1 = true;
// 型推論
var m1 = 5; // int
var n1 = "world"; // string
Console.WriteLine(s);
Console.WriteLine(c);
Console.WriteLine(i1);
Console.WriteLine(d);
Console.WriteLine(f);
Console.WriteLine(flag1);
Console.WriteLine(m1);
Console.WriteLine(n1);
//==============================
// 演算
//==============================
// + - * / %
var x = 10; // int
Console.WriteLine(x / 3); // 3
Console.WriteLine(x % 3); // 1
Console.WriteLine(x / 3.0); // 3.333....
Console.WriteLine(x / (double)3); // 3.333....
// ++ --
var y = 5;
y++;
Console.WriteLine(y); // 6
y--;
Console.WriteLine(y); // 5
var z = 6;
// z = z + 10;
z += 10;
// AND OR NOT
// && || !
var flag = true;
Console.WriteLine(!flag);
//==============================
// 文字列
//==============================
Console.WriteLine("hello " + "world");
// \n, \t 改行、タブ
Console.WriteLine("hell\no wo\trld");
var name1 = "taguchi";
var score1 = 52.3;
Console.WriteLine(string.Format("{0} [{1}]", name1, score1)); // taguchi [52.3]
Console.WriteLine($"{name1} [{score1}]"); //C# 6以降
Console.WriteLine($"{name1, -10} [{score1, 10}]");
Console.WriteLine($"{name1, -10} [{score1, 10:0.00}]");
Console.WriteLine($"{name1, -10} [{score1 + 25, 10:0.00}]");
//==============================
// if
//==============================
// var score2 = int.Parse(Console.ReadLine());
var score2 = int.Parse("90");
// > >= < <= == !=
if (score2 > 80)
{
Console.WriteLine("Great!");
}
else if (score2 > 60)
{
Console.WriteLine("Good!");
}
else
{
Console.WriteLine("so so ...!");
}
Console.WriteLine((score2 > 80) ? "Great" : "so so ...");
//==============================
// switch
//==============================
// var signal = Console.ReadLine();
var signal = "red";
switch (signal)
{
case "red":
Console.WriteLine("Stop!");
break;
case "blue":
case "green":
Console.WriteLine("Go!");
break;
case "yellow":
Console.WriteLine("Caution!");
break;
default:
Console.WriteLine("wrong signal!");
break;
}
//==============================
// while
//==============================
// var i2 = 0;
var i2 = 100;
while (i2 < 10)
{
Console.WriteLine($"loop:{i2}");
i2++;
}
do
{
Console.WriteLine($"loop2:{i2}");
i2++;
} while (i2 < 10);
//==============================
// for
//==============================
// continue それ以降の処理を中止して次のループへ
// break ループ自体を抜ける
for (int i = 0; i < 10; i++)
{
if (i == 3)
{
continue;
}
if (i == 5)
{
break;
}
Console.WriteLine(i);
}
//==============================
// 配列
//==============================
// 配列
int[] scoresA1 = new int[3];
scoresA1[0] = 10;
scoresA1[1] = 30;
scoresA1[2] = 20;
int[] scoresA2 = new int[] { 10, 30, 20 };
int[] scoresA3 = { 10, 30, 20 };
var scoresA4 = new[] { 10, 30, 20 };
scoresA4[1] = 40;
Console.WriteLine(scoresA4[1]);
Console.WriteLine(scoresA2);
Console.WriteLine(scoresA3);
//==============================
// foreach
//==============================
var scoresB1 = new[] { 10, 30, 20 };
// for (int i = 0; i < scores.Length; i++) {
// Console.WriteLine(scores[i]);
// }
foreach (int score in scoresB1)
{
Console.WriteLine(score);
}
//==============================
// メソッド
//==============================
SayHi1();
Console.WriteLine(SayHi2());
Console.WriteLine(SayHi3());
SayHi4("Tom", 30); // tom 30
SayHi4("Bob"); // bob 23
SayHi4(age: 26, name: "Steve"); // steve 26
//==============================
// クラス
//==============================
User user = new User(); // インスタンス
Console.WriteLine(user.name); // me
user.SayHi(); // hi! me
user.name = "taguchi";
user.SayHi(); // hi! taguchi
User tom = new User("Tom");
tom.SayHi();
User user2 = new User();
user2.SayHi();
AdminUser bob = new AdminUser("Bob");
bob.SayHi();
bob.SayHello();
//==============================
// プロパティ
//==============================
Staff staff = new Staff();
Console.WriteLine(staff.Name);
staff.Name = "taguchi";
Console.WriteLine(staff.Name);
staff.Post = "Chief ";
Console.WriteLine(staff.Post);
//==============================
// インデクサ
//==============================
Team giants = new Team();
giants[0] = "taguchi";
giants[1] = "fkoji";
giants[2] = "dotinstall";
Console.WriteLine(giants[1]);
User.GetCount(); // 0
User userA1 = new User();
User userA2 = new User();
User userA3 = new User();
User.GetCount(); // 3
Console.WriteLine(userA1);
Console.WriteLine(userA2);
Console.WriteLine(userA3);
//==============================
// 抽象クラス
//==============================
Japanese aki = new Japanese();
aki.SayHi();
American mike = new American();
mike.SayHi();
//==============================
// インターフェース
//==============================
Partner partner = new Partner();
partner.Share();
//==============================
// ジェネリック
//==============================
MyData <string> s1 = new MyData <string>();
s1.GetThree("hello");
MyData <double> g1 = new MyData <double>();
g1.GetThree(23.3);
MyInteger mi = new MyInteger();
mi.GetThree(55);
//==============================
// 名前空間
//==============================
DotinstallNamespace.Player player1 = new DotinstallNamespace.Player();
Player player2 = new Player(); //using宣言しておけば、namespace省略可。
player1.SayHi();
player2.SayHi();
//==============================
// 構造体
//==============================
Point p1 = new Point(5, 3);
Point p2 = new Point(12, 4);
p1.GetInfo();
p2.GetInfo();
//==============================
// 列挙型
//==============================
Direction dir = Direction.Right;
Console.WriteLine((int)Direction.Right);
switch (dir)
{
case Direction.Stay:
// そのまま
break;
case Direction.Right:
// 右へ
break;
case Direction.Left:
// 左へ
break;
}
//==============================
// 例外
//==============================
MyExceptionPractice.Div(10, 0);
MyExceptionPractice.Div(10, -3);
//==============================
// デリゲート
//==============================
MyDelegate ShowMessage;
ShowMessage = SayHiFromDeligater; // デリゲートにメソッドを登録
ShowMessage += SayHelloFromDeligater; //メソッドを追加（マルチキャストデリゲート）
ShowMessage -= SayHelloFromDeligater; //登録の解除
ShowMessage(); // 実行
//==============================
// 匿名メソッド
//==============================
MyDelegate ShowMessage2;
ShowMessage2 = delegate {
Console.WriteLine("hi!(Anonymous methods)");
};
ShowMessage2();
//==============================
// ラムダ式
//==============================
MyDelegate ShowMessage3;
// ラムダ式: 引数 => 処理
ShowMessage3 = () => {
Console.WriteLine("hi!(Lambda expression)");
};
ShowMessage3 += () => Console.WriteLine("hello!(Lambda expression)");
ShowMessage3();
//==============================
// イベント
//==============================
MyButton btn = new MyButton();
// メソッドを登録できる（以下ではラムダ式を使用している）
btn.MyEvent += () => Console.WriteLine("Button Clicked!");
btn.OnClicked();
//==============================
// Collection
// - List（データの集合）
// - HashSet（順番を持たない、かつ重複を許さないデータの集合。順番を指定してアクセスする事はできない。）
// - Dictionary（キーと値でデータを管理していくデータの集合）
//※要using System.Collections.Generic;
//==============================
//------------
// List
//------------
List <int> scoresA = new List <int>();
scoresA.Add(30);
scoresA.Add(80);
scoresA.Add(60);
List <int> scoresB = new List <int>()
{
30, 80, 60
};
scoresB[1] = 100;
Console.WriteLine(scoresB.Count);
foreach (var score in scoresB)
{
Console.WriteLine(score);
}
//------------
// HashSet
//------------
HashSet <int> answers = new HashSet <int>()
{
3, 5, 8, 5
}; //重複分は無視される
answers.Add(10); // 3, 5, 8, 10
answers.Remove(3); // 5, 8, 10
Console.WriteLine(answers.Contains(3)); // false
foreach (var answer in answers)
{
Console.WriteLine(answer);
}
//------------
// Dictionary
//------------
Dictionary <string, int> registrants = new Dictionary <string, int>()
{
{ "taguchi", 50 },
{ "fkoji", 80 },
};
registrants.Add("dotinstall", 40);
Console.WriteLine(registrants["fkoji"]); // 80
registrants["taguchi"] = 60;
foreach (KeyValuePair <string, int> registrant in registrants)
{
Console.WriteLine($"{registrant.Key}: {registrant.Value}");
}
//==============================
// LINQ
//==============================
//要 using System.Linq;
List <double> prices = new List <double>()
{
53.2, 48.2, 32.8
};
//------------
// SQL
//------------
var resultsA = from price in prices
where price * 1.08 > 50.0
select price * 1.08;
foreach (var result in resultsA)
{
Console.WriteLine(result);
}
//------------
// Method
//------------
var results = prices
.Select(n => n * 1.08)
.Where(n => n > 50.0);
foreach (var result in results)
{
Console.WriteLine(result);
}
//-----< Sample01 >-----
List <Customer> _customers = new List <Customer>();
_customers.Add(new Customer {
Name = "Fukuzawa", Age = 35, IsMarried = true,
});
_customers.Add(new Customer {
Name = "Higuchi", Age = 28, IsMarried = true,
});
_customers.Add(new Customer {
Name = "Noda", Age = 42, IsMarried = false,
});
_customers.Add(new Customer {
Name = "Igawa", Age = 21, IsMarried = false,
});
_customers.Add(new Customer {
Name = "Sawada", Age = 31, IsMarried = true,
});
Console.WriteLine("====================");
// All
foreach (var customer in _customers)
{
Console.WriteLine(customer.Name);
}
Console.WriteLine("====================");
// フィルタリング１
foreach (var customer in _customers.Where(n => n.IsMarried))
{
Console.WriteLine(customer.Name);
}
Console.WriteLine("====================");
// フィルタリング２
foreach (var customer in _customers
.Where(n => n.IsMarried)
.Where(n => n.Age > 30)
)
{
Console.WriteLine(customer.Name);
}
Console.WriteLine("====================");
}