数组

using System.Collections;

// See aka.ms/new-console… for more information Console.WriteLine("Hello, World!"); Console.WriteLine("helo" + 1); //将1转换成字符串，不需要我们手动去强转 //强转 Convert.ToString() (String)值 //Convert.ToInt32(Console.ReadLine()); //Convert.ToString(Console.ReadLine());

//Console.WriteLine(Convert.ToInt32("1") - 2);

/* double num1 = 2.3; int num = (int)num1; Console.WriteLine(num); */

//数组 int[] intArray1 = {1,2,3 }; // 数组的长度是不是固定的？ 是固定的 int[] intArray2 = new int[4]; //定义数组的长度为4，默认每一个下标对应的值为0 //每一个值都有一个编号，索引，通过编号找到对应的值 Console.WriteLine(intArray2[1]); int[] intArray3 =new int[4] {1,2,3,4}; //3种方式 Console.WriteLine(intArray3[1]); intArray2[3] = 4; //更改数组元素 Console.WriteLine(intArray2[3]); //Console.Write;

/* 用for循环来遍历数组

*/ foreach(int i in intArray1) { Console.WriteLine(i); } for (int i = 0;i < intArray3.Length;i++) { Console.WriteLine(intArray3[i]); } //声明一个动态数组 ArrayList arrayList = new ArrayList() { 1, 2, 3, 4 ,35,1}; arrayList.Add(67); // 向数组中添加元素 arrayList.Insert(0, 10); //往指定的下标位置添加元素 arrayList.Remove(1); //移除数组中的1，只能移除一次 //arrayList.Remove(1);

foreach (int i in arrayList) { Console.Write(i+" "); //注意行输出 } Console.WriteLine(arrayList.Count); //看数组的个数 Console.WriteLine(arrayList.Capacity); //动态扩容

//字符串 string str1 = "abcdefg"; str1 = "abcdefge"; // 新开辟的空间，旧的值被释放 foreach (char i in str1) // int i in str 则打印出ascii码 { Console.WriteLine(i); } for(int i=0; i < str1.Length; i++) { Console.WriteLine(str1[i]); } str1 = str1.ToUpper(); //返回了一个新的字符串 Console.WriteLine(str1.ToUpper()); Console.WriteLine(str1.ToLower());

//截取字符串 str1 = str1.Substring(0, 3); //第一个参数是初始下标的位置，第二个参数是截取的s长度 Console.WriteLine(str1); string str2 = " tjm "; Console.WriteLine(str2.Trim()); Console.WriteLine(str2.TrimStart()); //去掉头空格 Console.WriteLine(str2.TrimEnd()); //去掉尾空格

string str3 = "小明 - 1234567890 - 男"; string[] personInfo = str3.Split("-"); //通过字符-进行分割 foreach(string i in personInfo) { Console.Write(i + ""); } //有分割就有合并 join(str.","); str2 = string.Join(",",personInfo); Console.WriteLine(str2);

/*int a = 0; int kongping = 0; int keleping = 364; while (true) { keleping -= 1; a += 1; kongping += 1;

if (kongping == 3)
{
    kongping -= 3;
    keleping += 1;
}
if(keleping == 0)
{
    Console.WriteLine("喝可乐的次数:{0}",a);
    Console.WriteLine("还剩下空瓶的个数:{0}",kongping);
    break;
}

}*/ /*int bottle = 364; int drinkNum = bottle; int emptyNum = bottle; while (emptyNum > 2) {

drinkNum += emptyNum / 3;
emptyNum = emptyNum / 3 + emptyNum % 3;

} Console.WriteLine("{0},,,{1}s",emptyNum,drinkNum);*/

char[] charArray = Console.ReadLine().ToCharArray(); //转成字符数组 for(int i = 0; i < charArray.Length; i++) { if ('a' <= charArray[i] && charArray[i] <='z' || 'A' <= charArray[i] && charArray[i] <= 'Z') { if('w' <= charArray[i] || 'W' <= charArray[i] && charArray[i] <= 'Z') { charArray[i] = (char)(charArray[i] - 22); } else { charArray[i] = (char)(charArray[i] - 3); }

}

} Console.WriteLine(String.Join("",charArray)); int a = 0; for (int i = 0; i < charArray.Length; i++) { Console.WriteLine((int)charArray[i]); } /* Console.WriteLine(charArray[i]); foreach (char i in str1) // int i in str 则打印出ascii码 { Console.WriteLine(i); } */