• C#第六章学习代码


    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace _6._1_字符及转义字符
    {
        class Program
        {
            static void Main(string[] args)
            {
    
                //char mychar1 = '0';
                //char mychar2 = 'a';
                //char mychar3 = '男';
                //int myint = 120;
                //Console.WriteLine(mychar1+"  "+mychar2 + "  " + mychar3);
    
               
                //char mychar1 = 'a';
                //char mychar2 = '0';
                //char mychar3 = 'A';
                //if (char.IsLetter(mychar1))
    
                //Console.WriteLine(char.ToUpper(mychar1));
                //if (char.IsDigit(mychar2)) Console.WriteLine("mychar2是数字");
    
                //Console.WriteLine(char.ToLower(mychar3));
                Console.WriteLine("这是第一段话
    这是第二段话");
                Console.WriteLine("D:\Users\Walker\Documents\Visual Studio 2015\Projects\51zxwProjects");
                Console.WriteLine(@"D:UsersWalkerDocumentsVisual Studio 2015Projects51zxwProjects");
              
                Console.ReadKey();
            }
        }
    }
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace _6._2_字符串简介
    {
        class Program
        {
            static void Main(string[] args)
            {
                //string字符串,可以看成是一个没有上限的存储
                //char类型,它是一个0-2^16
                string mystr1 = "这是一句中文";
                string mystr2 = "1234567980";
                string mystr3 = "abcdefg";
                Console.WriteLine(mystr1);
                Console.WriteLine(mystr2);
                Console.WriteLine(mystr3);
                Console.ReadKey();
            }
        }
    }
    

      

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace _6._3_字符串的大小写转换
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Console.WriteLine("请输入您的英文姓名");
                //string mystr = Console.ReadLine();
                ////ToUpper方法可实现将英文转换为大写
                //if (mystr.ToUpper() == "JACK") Console.WriteLine("这么巧,我也叫JACK");
                //else Console.WriteLine("您的名字很有个性");
    
                //string mystr = "this is an example of conversation on string";
                //Console.WriteLine("大写字符串:"+mystr.ToUpper());
                //Console.WriteLine("小写字符串:"+mystr.ToLower());
    
                //char mychar = 'a';
                //Console.WriteLine("小写字符:"+char.ToLower(mychar));
                //Console.WriteLine("大写字符:"+char.ToUpper(mychar));
                //Console.ReadKey();
    
                    Console.ReadKey();
    
    
    
    
    
    
    
            }
        }
    }
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace _6._4_字符串的比较
    {
        class Program
        {
            static void Main(string[] args)
            {
    
                //==  !=
    
                //Equals
                string mystr1 = "Hello";
                string mystr2 = "HELLO";
                Console.WriteLine(string.Equals(mystr1,mystr2));
    
                Console.WriteLine(string.Compare(mystr1,mystr2,true));
                Console.WriteLine(mystr1.CompareTo(mystr2));
                Console.ReadKey();
            }
        }
    }
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace _6._5_字符串的格式化
    {
        class Program
        {
            static void Main(string[] args)
            {
                //Console.WriteLine("{0:C}",21.3);
                //Console.WriteLine("字符串的格式化输出");
                //string s = string.Format("默认格式:-----{0}
    "+"使用C格式:{0:C}
    "+"使用D格式:{0:D}
    "+"使用E格式:{1:E}
    "+"使用F格式:{1:F}
    "+"使用G格式:{0:G}
    "+ "使用N格式:{0:N}
    " + "使用P格式:{0:P1}
    " + "使用X格式:{0:X}
    ",2100,2100.33);
                //Console.WriteLine(s);
                for (int i = 001; i < 051; i++)
                {
    
                    string mystr = string.Format("{0:D3}",i);
                   Console.WriteLine(mystr);
                }
                Console.ReadKey();
            }
        }
    }
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace _6._6_字符串的截取
    {
        class Program
        {
            static void Main(string[] args)
            {
                //string mystr = "walker";
                //string mystr0 = mystr.Substring(2,2);
                //Console.WriteLine(mystr0);
                Console.WriteLine("请输入一个单词,不区分大小写");
                string mystr = Console.ReadLine();
                string firstCapital = mystr.Substring(0, 1).ToUpper();
                string otherCpaital = mystr.Substring(1).ToLower();
                Console.WriteLine("单词首字母大写"+firstCapital+otherCpaital);
                Console.ReadKey();
            }
        }
    }
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace _6._7_字符串的分割
    {
        class Program
        {
            static void Main(string[] args)
            {
                string mystr = "51zxw-C#-Walker=6.7字符串的分割";
                Console.WriteLine("原字符串为"+mystr);
                //Console.WriteLine("用-分割后的字符串为:");
                //string[] changeMystr = mystr.Split('-');
                //foreach (string outstr in changeMystr) Console.Write(outstr+"	");
    
    
                Console.WriteLine("用-和=分割后的字符串为:");
                string[] changeMystr = mystr.Split(new char[] { '-','='});
                foreach (string outstr in changeMystr) Console.Write(outstr+"	");
                Console.ReadKey();
            }
        }
    }
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace _6._._8_字符串的合并
    {
        class Program
        {
            static void Main(string[] args)
            {
                Console.WriteLine("字符串的合并");
                string mystr1 = "51zxw";
                string mystr2 = "C#";
                string mystr3 = "Walker";
                string changeMystr = mystr1 + mystr2 + mystr3;
                Console.WriteLine("第一种方法(+)");
                Console.WriteLine(changeMystr);
                Console.WriteLine("第二种方法(Concat)");
                string changeMystr2 = string.Concat(mystr1,mystr2,mystr3);
                Console.WriteLine(changeMystr2);
                Console.WriteLine("第三种方法");
                string[] mystrArray = { "51zxw","C#","walker"};
                string changeMystr3 = string.Join("***", mystrArray);
                Console.WriteLine(changeMystr3);
                Console.ReadKey();
            }
        }
    }
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace _6._9_字符串的插入与填充
    {
        class Program
        {
            static void Main(string[] args)
            {
    
                //字符串的插入
                string mystr = "51zx.net";
                string insertMystr = mystr.Insert(8,"w");
                Console.WriteLine("字符串的插入");
                Console.WriteLine(insertMystr);
                //PadRight用来在字符串的结尾处添加指定(重复)字符以达到指定的总长度,总长度直接用数字来指定
                string padStr = "abc";
                string padStr2 = "abcd";
                string padStr3 = "efghi";
                string padRightStr = padStr.PadRight(6, '/')+"
    "+padStr2.PadRight(6,'/')+"
    "+padStr3.PadRight(6,'/');
                Console.WriteLine("字符串结尾处填充");
                Console.WriteLine(padRightStr);
                //PadLeft用来在字符串的开头处添加指定的字符以达到我们指定的总长度
                string padLeftStr = padStr.PadLeft(6) + "
    " + padStr2.PadLeft(6) + "
    " + padStr3.PadLeft(6);
                Console.WriteLine("字符串开始位置填充");
                Console.WriteLine(padLeftStr);
                
    
                Console.ReadKey();
            }
        }
    }
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace _6._10_字符串的删除_移除_
    {
        class Program
        {
            static void Main(string[] args)
            {
                //通过Remove方法来实现字符串的移除
    
                //第一种方法 从指定位置开始移除后边的字符串
                string mystr = "xw.net//12345\5464";
                string changeMystr = mystr.Remove(13);
                Console.WriteLine("用一个参数实现Remove的结果");
                Console.WriteLine(changeMystr);
                //第二种方法 从指定位置开始移除指定位数的字符串
                string mystr2 = "w.comt";
                string changeMystr2 = mystr2.Remove(9,4);
                Console.WriteLine("用两个参数实现Remove的结果");
                Console.WriteLine(changeMystr2);
                Console.ReadKey();
    
            }
        }
    }
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace _6._11_字符串的修剪
    {
        class Program
        {
            static void Main(string[] args)
            {
    
                //字符串的修剪通过Trim()来实现
                string userName = "    walker     ";
                Console.WriteLine("原字符串是:"+userName+"|");
                Console.WriteLine("把空格修剪后是:"+userName.Trim()+"|");
                //修剪开始用TrimStart()
                Console.WriteLine("修剪开始空格后是:"+userName.TrimStart()+"|");
    
                //修剪结尾用TrimEnd()
                Console.WriteLine("修剪结尾空格后是:" + userName.TrimEnd() + "|");
                //将"#%%##%#http:/t#%"修剪为.net"
                string mywebsite = "#%%##%##%";
                Console.WriteLine("修剪其他字符的方法1:"+mywebsite.Trim('#','%'));
                Console.WriteLine("修剪其他字符的方法2:" + mywebsite.Trim("#%".ToCharArray()));
    
                Console.ReadKey();
            }
        }
    }
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace _6._12_字符串的复制
    {
        class Program
        {
            static void Main(string[] args)
            {
                //C#当中复制字符串是通过Copy和CopyTo来实现的
                //Copy  静态方法:string.方法来进行引用
                string mystr = "zxw.net";
                string copyMystr = string.Copy(mystr);
                Console.WriteLine(copyMystr);
                //CopyTo 非静态方法
                char[] mycharArray = new char[20];
    
                mystr.CopyTo(7,mycharArray,0,13);
                Console.WriteLine("CopyTo实现复制的结果是:");
                Console.WriteLine(mycharArray);
                Console.ReadKey();
            }
        }
    }
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace _6._13_字符串的替换
    {
        class Program
        {
            static void Main(string[] args)
            {
                //字符串的替换
                //C#中实现的方法是 非静态方法Replace
           
                string mystr = "xw.net";
                Console.WriteLine("替换前字符串为:"+mystr);
                Console.WriteLine("C#利用Replace进行替换的结果"+mystr.Replace('w', 'W'));
                Console.ReadKey();
            }
        }
    }
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace _6._14_字符串的查找
    {
        class Program
        {
            static void Main(string[] args)
            {
                //IndexOf方法
                //string mystr = "12351zxw45651zxw";
                ////              0123456789ABCDEF
                //int myReturnVal1 = mystr.IndexOf("51zxw");
                //int myReturnVal2 = mystr.LastIndexOf("51zxw");
    
                //Console.WriteLine(myReturnVal1);
                //Console.WriteLine(myReturnVal2);
    
                Console.WriteLine("请您输入一个字符串,我们来判断是否包含51zxw及它出现第一次和最后一次的位置");
                string mystr = Console.ReadLine();
                int myReturnVal1 = mystr.IndexOf("51zxw");
                int myReturnVal2 = mystr.LastIndexOf("51zxw");
                if (myReturnVal1 < 0) Console.WriteLine("您输入的字符串不包含51zxw");
                else
                {
                    Console.WriteLine("您输入的字符串包含51zxw,它第一次出现的位置是第{0}位,最后一次出现的位置是第{1}位", myReturnVal1+1,myReturnVal2+1);
    
                }
                Console.ReadKey();
            }
        }
    }
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace _6._15_类型转换
    {
        class Program
        {
            static void Main(string[] args)
            {
                //类型转换
                //隐式转换
                // char mychar = 'a';
                //int myint = 10;
    
    
    
                //Console.WriteLine(mychar);
                //Console.WriteLine(myint);
    
                ////myint = mychar;
                ////Console.WriteLine(myint);
    
                //mychar = checked((char)myint);
                //Console.WriteLine(mychar);
                int myint = 100;
                string mystr = "456";
    
                //myint = Convert.ToInt32(mystr);
                //mystr = Convert.ToString(myint);
                //mystr = myint.ToString();
                myint = int.Parse(mystr);
                Console.WriteLine(myint);
    
    
    
    
    
    
    
    
    
                Console.ReadKey();
            }
        }
    }
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace _6._16_类型转换_2_
    {
        class Program
        {
            static void Main(string[] args)
            {
                double mydouble = 5.5;
                int myint = 100;
                string mystring = "256";
                string stringResult;
                int intResult;
                //string→int
    
                //(int) 此方法不适用于将string转换为int,只能转换数值类型为int,而不能转换引用类型
                //不会进四舍五入,直接舍掉小数
                //intResult = (int)mydouble;
                //Console.WriteLine(intResult);
    
                //Convert.ToInt32() 它会将空值NULL转换为0
                //0-4:直接舍掉
                //5:看整数位,4.5 5  6 返回一个临近的偶数
                //6-9:进位
    
                //intResult = Convert.ToInt32(mydouble);
                //Console.WriteLine(intResult);
    
                ////int.Parse();不能转换空值 只能将string转换为int
                //intResult = int.Parse(mystring);
                //Console.WriteLine(intResult);
    
                //int→string
                //强制括号转换只能转换数值类型的 stringResult = (string)myint;
                stringResult = Convert.ToString(myint);
    
                stringResult = myint.ToString();
    
               
    
                Console.ReadKey();
            }
        }
    }
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;//引入命名空间
    using System.Threading.Tasks;
    
    namespace _6._17_StringBuilder类
    {
        class Program
        {
            static void Main(string[] args)
            {
                StringBuilder mystringBuilder = new StringBuilder("1zxw.net");
                Console.WriteLine("=================Append===================");
                //追加对应的字符串
                Console.WriteLine(mystringBuilder.Append("是一个神奇的网站"));
                Console.WriteLine("==================Insert===================");
                //在对应位置插入指定的字符串
                Console.WriteLine(mystringBuilder.Insert(20,"
    "));
                Console.WriteLine("======================Remove==============");
                //移除从索引开始位置的N个字符
                Console.WriteLine(mystringBuilder.Remove(20,1));
                Console.WriteLine("====================Replace===============");
                Console.WriteLine(mystringBuilder.Replace("神奇","强大"));
                Console.WriteLine("======================AppendFormat=======");
                //按照指定的格式来添加对应的字符串
                int saveMoney = 2000;
                Console.WriteLine(mystringBuilder.AppendFormat("并且为我省了{0:C}",saveMoney));
                Console.WriteLine("=========================AppendLine=======");
                Console.WriteLine(mystringBuilder.AppendLine("这句话会自动换行"));
    
                Console.ReadKey();
    
            }
        }
    }
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Text;
    using System.Threading.Tasks;
    
    namespace _6._18_本章小结及任务实施
    {
        class Program
        {
            static void Main(string[] args)
            {
                Console.WriteLine("请输入两个字符串,每个字符串以回车确认输入,我们将会以"|"来进行分隔 :");
                string mystr1 = Console.ReadLine();
                string mystr2 = Console.ReadLine();
                string maxstr;
                if (string.Compare(mystr1, mystr2) > 0) maxstr = mystr1;
                else maxstr = mystr2;
                Console.WriteLine("您输入的两个字符串分别是:{0},{1}",mystr1,mystr2);
                //利用SubString来进行分隔
                Console.WriteLine("拆分较大字符串后的结果是:");
                for (int i = 0; i < maxstr.Length; i++)
                {
                    Console.Write(maxstr.Substring(i, 1));
                    if(i!=maxstr.Length-1)Console.Write("|");
                }
                Console.ReadKey();
            }
        }
    }
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  • 原文地址:https://www.cnblogs.com/zqyo2000z/p/5338869.html
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