第3章 变量和表达式

变量命名约定：

1.PascalCase 帕斯卡拼写法

Age

LastName

WinterOfDiscontent

2.camelCase 骆驼拼写法

age

firstName

timeOfDeath

区别：两种命名约定都应用到由多个单词组成的名称中，并指定名称中的每个单词除了第一个字母大写外，其余字母都是小写。在camelCase中，还有个规则，即第一个单词以小写字母开头；

建议：简单的变量使用camelCase规则；对于比较高级的命名则使用PascalCase;

static void Main(string[] args)
{
/*This is a comment*/
/*And so...
...is this!*/
//This is a different sort of comment.
// <A statement>; //Explanation of statement
/*#region Using directives
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
#endregion*/
//使用简单类型变量
/*int myInteger;
string myString;
myInteger=17;
myString="\"myInteger\" is ";//转义序列\转义双引号
//myString = "This string has a\nline break.";
//myString = @"C:\Temp\MyDir\MyFile.doc";
Console.WriteLine("{0}{1}.", myString, myInteger);
Console.ReadKey();
//@"C:\Temp\MyDir\MyFile.doc"*/
//变量的声明和赋值
int xSize = 4 , ySize = 5 , zSize = 6 , aSize = 7 ;
xSize = ySize++ * --zSize;
Console.WriteLine("{0}{1}{2}{3}", xSize, ySize, zSize, aSize);
Console.ReadKey();

}

3.

static void Main(string[ ] args)意思？

static 静态的
void 空返回值
Main 方法名，在这个地方为主方法，每个程序只能有一个Main
()表示方法里面的参数
string[] args：string表示参数类型为一个字符串数组，args表示参数名称

这句话你记住格式就行了，不会有什么改变的，就是一个主方法固定声明的格式。

4.verbatim string literal

逐字字符串字面量；原义字符串；逐字字符串字面变量

C# 支持两种形式的字符串：常规字符串 (regular string literal) 和原义字符串 (verbatim string literal)。

查看相关

5.

||

subtracting

英[səbt'ræktɪŋ]

美[səbt'ræktɪŋ]

减去; 减，扣除，做减法( subtract的现在分词 );
ex:the result of subtracting a from b is c;||

||sum[英][sʌm][美][sʌm]
n.总数; 算术; 金额; 概略，要点;
vt.& vi.总计; 总结，概括; 归纳;

ex: the sum of a and b is c;||

||

product

英[ˈprɒdʌkt]

美[ˈprɑ:dʌkt]

n.	产品; 乘积; 结果; 作品;

ex:the product of a and b is c;||

||dividing by 除法

ex:the result of dividing a by b is c;||

remainder[英][rɪˈmeɪndə(r)][美][rɪˈmendɚ]
n.剩余物; 其他人员; 差数; 廉价出售的图书;
vt.廉价出售（书）; 廉价出售;
adj.剩余的; 留存下的;

ex:the remainder after dividing a by b is c .

代码示例：

static void Main(string[] args)
{
//变量赋值、用户输入、类型转换、加减乘除余数
/*double firstNumber, secondNumber;
string userName;
Console.WriteLine("Enter your name:");
userName = Console.ReadLine();
Console.WriteLine("Welcome {0} !", userName);
Console.WriteLine("Now give me a number :");
firstNumber=Convert.ToDouble(Console.ReadLine());
Console.WriteLine("Now give me another number :");
secondNumber = Convert.ToDouble(Console.ReadLine());
Console.WriteLine("The sum of {0} and {1} is {2}.", firstNumber, secondNumber, firstNumber + secondNumber);
Console.WriteLine("The result of subtracting {0} from {1} is {2}.", secondNumber, firstNumber, firstNumber - secondNumber);
Console.WriteLine("The product of {0} and {1} is {2}.", firstNumber,secondNumber,firstNumber * secondNumber);
Console.WriteLine("The result of dividing {0} by {1} is {2}.", firstNumber, secondNumber, firstNumber / secondNumber);
Console.WriteLine("The remainder after dividing {0} by {1} is {2}.", firstNumber, secondNumber, firstNumber % secondNumber);
Console.ReadLine();*/
int firstNumber, secondNumber, thirdNumber, fourthNumber;
Console.WriteLine("Give me a number :");
firstNumber = Convert.ToInt32(Console.ReadLine());
Console.WriteLine("Give me another number :");
secondNumber = Convert.ToInt32(Console.ReadLine());
Console.WriteLine("Give me another number :");
thirdNumber = Convert.ToInt32(Console.ReadLine());
Console.WriteLine("Give me another number :");
fourthNumber = Convert.ToInt32(Console.ReadLine());
Console.WriteLine("The product of {0}, {1}, {2}, and {3} is {4}.", firstNumber, secondNumber, thirdNumber, fourthNumber, firstNumber * secondNumber * thirdNumber * fourthNumber);
Console.ReadLine();

}