c#流程控制

c#分支语句

namespace ConsoleApp1
{internal class Program{static void Main(string[] args){Console.WriteLine("请输入学生成绩");string s=Console.ReadLine();int a=int.Parse(s);//将字符类型强制转换为int类型if (a >= 90){ Console.WriteLine("成绩优秀");}else{Console.WriteLine("成绩一般");}}}
}

namespace ConsoleApp1
{internal class Program{static void Main(string[] args){Console.WriteLine("请输入一个数");int x=Convert.ToInt32(Console.ReadLine());Console.WriteLine("请输入运算类型");char z=Convert.ToChar(Console.ReadLine());Console.WriteLine("请输入另一个数字");int y=Convert.ToInt32(Console.ReadLine());switch (z){case '+':Console.WriteLine("计算结果{0}",x+y);break;case '-':Console.WriteLine("计算结果是{0},x-y");break;case '*':Console.WriteLine("计算结果是{0}", x * y);break;default:Console.WriteLine("不认识计算类型");break;}       }}
}

循环语句

while 循环

namespace ConsoleApp1
{internal class Program{static void Main(string[] args){int a = 10;  //定义一个局部变量while (a>0){Console.WriteLine("第{0}个 hello world",a);a = a - 1;}}}
}

for 循环

namespace ConsoleApp1
{internal class Program{static void Main(string[] args){string[] a=new string[3] ;for (int i=0;i<3;i++){Console.WriteLine("请输入字符");a[i] = Console.ReadLine();}Console.WriteLine(a);for (int i=0;i<3; i++){Console.WriteLine(a[i]);}}}
}

namespace ConsoleApp1
{internal class Program{static void Main(string[] args){//foreach 用于遍历集合中所有元素string[] name = new string[6]; //定义一个字符串数组//for 循环来给数组进行赋值for (int i = 0;i < name.Length; i++){Console.WriteLine("请输入第{0}个学生姓名",i);name[i] = Console.ReadLine();}//foreach来输出字符串数组元素foreach (string a in name){Console.WriteLine("{0}", name.Length);Console.WriteLine("{0}", a);}int name_lenth = name.Length;//逆序输出while(name_lenth > 0){Console.WriteLine(name[name_lenth-1]);name_lenth--;}}}
}