using System;
namespace _006_变量研究
{
class Program
{
static void Main(string[] args)
{
int a = 23, b = 45;
// 23+45=68
//Console.WriteLine(a + "+" + b + "=" + (a + b));
Console.WriteLine("{0}+{1}={2}", a, b, a + b);//0 1 2
Console.WriteLine("两个数字相加{0}+{0}={2}",34,123,4);
//Console.WriteLine("两个数字相加{0}+{0}={3}",34,123,4);//不存在{3}报错
}
}
}
using System;
namespace _006_变量研究
{
class Program
{
static void Main(string[] args)
{
//int class namespace string void
int age;
int myAge;
int xiaomingAge;
double enemyHp;
double PI;
int HP;
int MP;
}
}
}
变量驼峰命名；
方法和类名Pascal命名。
using System;
namespace _006_变量研究
{
class Program
{
static void Main(string[] args)
{
int a = 5, b = 10;
//a = b;
//b = a;
//int temp = a;
//a = b;
//b = temp;
a = a + b;
b = a - b;
a = a - b;
Console.WriteLine(a);
Console.WriteLine(b);
}
}
}
减法交换变量：
a = a - b;//5-10=-5
b = b + a;//10+(-5)=5
a = b - a;//5-(-5)=10
using System;
namespace _005_练习题
{
class Program
{
static void Main(string[] args)
{
//int a = Convert.ToInt32(Console.ReadLine());
//int b = Convert.ToInt32(Console.ReadLine());
//int c = a + b;
//Console.WriteLine(c);
int a = Convert.ToInt32(Console.ReadLine());
int b = Convert.ToInt32(Console.ReadLine());
int c = (a + b) / 2;
Console.WriteLine(c);
}
}
}
using System;
namespace _004_字符类型
{
class Program
{
static void Main(string[] args)
{
//怎么读取数据 输入数据
//string str = Console.ReadLine(); // "12" 12
//Console.WriteLine(str + "-");
//1、类型一致 2、右边的值所需要的容器大小 小于等于左边的容器
//int a = Console.ReadLine();
string str = Console.ReadLine();// "12" 12
int strInt = Convert.ToInt32(str);// "12" 12 "df"
int a = Convert.ToInt32(Console.ReadLine());
Console.WriteLine(strInt + "-" + a);
}
}
}
using System;
namespace _004_字符类型
{
class Program
{
static void Main(string[] args)
{
//char a = 'c';
//int b = a;
//Console.WriteLine(a);
//Console.WriteLine(b);//99
//97 a
//int a = 97;
//char b = (char)a;//强制类型转换 强塞
//Console.WriteLine(a);
//Console.WriteLine(b);
//char a = '1';
//int b = a;
//Console.WriteLine(a);
//Console.WriteLine(b);
//char a = '\n';
//char b = '\\';
//char c = '\"';
//char d = '\t';
//char e = '\'';
//Console.WriteLine("c:\\a\\b\\c");
//Console.WriteLine(@"c:\a\b\c");
//Console.WriteLine(@"c:\\a\\b\\c");
//string str = @"www.sikiedu.com\nsiki";
// string str = @"www.sikiedu.com ""
//abc
//123
//456789";
// Console.WriteLine(str);
string str = "123" + "456";
string str2 = str + "www";
Console.WriteLine("www" + 123);
}
}
}
using System;
namespace _004_字符类型
{
class Program
{
static void Main(string[] args)
{
//char a = 'c';
//int b = a;
//Console.WriteLine(a);
//Console.WriteLine(b);//99
//97 a
int a = 97;
char b = (char)a;//强制类型转换 强塞
Console.WriteLine(a);
Console.WriteLine(b);
}
}
}
using System;
namespace _003_变量
{
class Program
{
static void Main(string[] args)
{
int a = 3, b = 8;
Console.WriteLine(a + b);//11
Console.WriteLine("a + b");//a + b
Console.WriteLine(a + "+" + b);//3+8
Console.WriteLine("a+b" + a + b);//a+b38
Console.WriteLine("a+b" + (a + b));//a+b11
}
}
}
using System;
namespace _003_变量
{
class Program
{
static void Main(string[] args)
{
int total;
//赋值
total = 4;
//int a;
//a = 1;
//int b = 1;
int a = 1;
a = 3 + 7 - 2;
int b = 3;
b = b + 1;
Console.WriteLine(a);
Console.WriteLine(b);
int c;
c = 10;//初始化
c = 11;
Console.WriteLine(c);
//female male
char sex = 'f';
sex = 'm';
}
}
}
using System;
namespace _003_变量
{
class Program
{
static void Main(string[] args)
{
//创建变量
//创建了一个数据的容器，容器的名字叫做age，容器的类型是int
//声明了一个变量，变量的名字是age
int age; //int变量类型 age变量名
//往容器里面放东西 赋值
age = 10;
double age2;
char age3;
double height;
char sex;
int count;
double ave;
int total;
double temperature;
}
}
}
C#编译
代码 -> 程序集（exe dll）
程序集在运行的时候会编译成机器指令（JIT 及时编译）
using System;
namespace _002_练习
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("*");
Console.WriteLine("**");
Console.WriteLine("***");
Console.WriteLine("****");
Console.WriteLine("*");
Console.WriteLine("*");
Console.WriteLine("*");
}
}
}
2
using System;
namespace _002_练习
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine(" *");
Console.WriteLine(" ***");
Console.WriteLine(" *****");
Console.WriteLine("*******");
Console.WriteLine(" *");
Console.WriteLine(" *");
Console.WriteLine(" *");
}
}
}
3
using System;
namespace _002_练习
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("\\\"");
}
}
}
4
using System;
namespace _002_练习
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("SiKi说:\"what is\\n\"");
}
}
}
using System; //注释：引入命名空间
namespace _001_开始
{
//这个是Program类
class Program
{
//这个是Main方法
static void Main(string[] args)
{
//ctrl + k ctrl + c
//Console.WriteLine("Hello World!1");//这个是输出语句
/*
sdf
sdf sdf
sdf
*/
//Console.WriteLine("Hello World!2");
//Console.WriteLine("Hello World 你好，世界3");
//Console.Write("Hello,World!");
//Console.Write("www.sikiedu.com");
Console.WriteLine("Hello ");
Console.WriteLine("World!");
Console.WriteLine("He\tllo \nWorld!\\");
}
}
}
（1）注释：
单行注释 //
多行注释 /* zhushi */
注释快捷键：ctrl+k ctrl+c
取消注释快捷键：ctrl+k ctrl+u
（2）语句结束加上 ;
（3）代码块 { }
（4）顺序执行
（5）Write 输出后不换行，WriteLine 输出后换行。
using System; //注释：引入命名空间
namespace _001_开始
{
//这个是Program类
class Program
{
//这个是Main方法
static void Main(string[] args)
{
//ctrl + k ctrl + c 注释快捷键
Console.WriteLine("Hello World!1"); //这个是输出语句
/* 多行注释
sdf
sdf sdf
sdf
*/
Console.WriteLine("Hello World!2");
Console.WriteLine("Hello World 你好，世界3");
}
}
}
using System; //注释：引入命名空间
namespace _001_开始
{
class Program
{
static void Main(string[] args)
{
Console.WriteLine("Hello World!");
Console.WriteLine("Hello World!");
}
}
}
Consolas 和 JetBrains Mono 字体，适合 程序员 写代码用。
1.38 11
2.a+b
3.3+8
4.a+b38
5.a+b11
1错2错3对4错5错6对
3
