/*
 *   2018年6月20日20:01:33
 *   代码目的：
 *   演示命名空间由类组成。类由方法和属性构成。
 *   属性的权限有public， protected， private组成
 *   并且程序的入口从某个类的static void Main()函数开始
 *   在类中的普通成员可以在方法中自由访问。
 *   演示访问权限的使用
 *   输出到控制台Console.WriteLine函数的演示，并且打印变量值的代码控制。
 *   演示C#中类型转换
 *   演示C#中string类型的使用
 */
using System;

namespace RectangleApplication
{
    class Rectangle
    {
        // 成员变量
        public double length;
        double width;
        public void Acceptdetails()
        {
            length = 4.5;
            width = 3.5;
        }
        public double GetArea()
        {
            return length * width;
        }
        public void Display()
        {
            //打印某个变量，用{0}, {1}表示
            Console.WriteLine("Length: {0}, Width: {1}", length, width);
            Console.WriteLine("Width: {0}", width);
            Console.WriteLine("Area: {0}", GetArea());
        }
    }

    class ExecuteRectangle
    {
        static void Main(string[] args)
        {
            Rectangle r = new Rectangle();
            //受保护级别限制
            //r.length = 5;
            r.Acceptdetails();
            r.Display();
            r.length = 4;
            r.Display();
            //转义字符'\'
            string str = "C:\\Windows";

            Console.WriteLine("Size of int: {0}", sizeof(int));
            Console.WriteLine("Size of uint: {0}", sizeof(uint));
            Console.WriteLine("{0}", str);
            Console.WriteLine("{0}", str.Length);

            Console.WriteLine("=======================");
            string[] a1 = new string[] { "a", "b", "c" };
            string[] a2 = a1;

            for (int i = 0; i < a2.Length; i++)
            {
                Console.Write(a2[i] + " ");    //a b c
            }
            a1[2] = "d";
            Console.WriteLine();            //换行

            for (int i = 0; i < a2.Length; i++)
            {
                Console.Write(a2[i] + " ");    //a b d
            }
            Console.WriteLine();

            Console.WriteLine("========================");
            Console.WriteLine("String 是一种特殊的引用类型");
            string a = "123";
            string b = a;
            Console.WriteLine(a + " " + b);  //123 123
            //此处需要注意
            b = "456";
            Console.WriteLine(a + " " + b);  //123 456

            Console.WriteLine("===============");
            Console.WriteLine("类型转换");
            double d = 5673.74;
            int ia;
            // 强制转换 double 为 int
            ia = (int)d;
            Console.WriteLine(ia);

            ia = 75;
            float f = 53.005f;
            bool b1 = true;
            Object oo = f;

            Console.WriteLine(ia.ToString());
            Console.WriteLine(f.ToString());
            Console.WriteLine(d.ToString());
            Console.WriteLine(b1.ToString());
            Console.WriteLine();

            Console.WriteLine("=============");
            Console.WriteLine("类型之间的转换");
            string locstr = 123.ToString();

            //如果要将"locstr"转成整型数
            int ii;
            //方法一: 用 Convert 
            ii = Convert.ToInt16(locstr);
            Console.WriteLine("ii: {0}", ii);
            //方法二: 用 Parse
            ii = int.Parse(locstr);

            Console.WriteLine();

            Console.WriteLine("=============");
            string s1 = "abcd";
            string s2 = "1234";
            int aa, bb;
            bool bo1 = int.TryParse(s1, out aa);
            Console.WriteLine(s1 + " " + bo1 + " " + aa);
            bool bo2 = int.TryParse(s2, out bb);
            Console.WriteLine(s2 + " " + bo2 + " " + bb);

            try
            {
                Console.WriteLine("输入数字，将计算出它加一的答案");
                int aaa = int.Parse(Console.ReadLine());   //有可能会抛出异常
                Console.WriteLine("答案是{0}", ++aaa);   //如果没有异常，程序才会进入这一步
            }
            catch (Exception)
            {
                Console.WriteLine("无法转换");  //如果捕获到异常，就说“无法转换”
            }
            Console.ReadLine();
        }
    }
}

/*
Length: 4.5, Width: 3.5
Width: 3.5
Area: 15.75
Length: 4, Width: 3.5
Width: 3.5
Area: 14
Size of int: 4
Size of uint: 4
C:\Windows
10
=======================
a b c
a b d
========================
String 是一种特殊的引用类型
123 123
123 456
===============
类型转换
5673
75
53.005
5673.74
True

=============
类型之间的转换
ii: 123

=============
abcd False 0
1234 True 1234
输入数字，将计算出它加一的答案
3
答案是4

 */