说明
1-100while求和
static void Main(string[] args)
{
Sum();
}
static void Sum()
{
int i = 2;
int sum = 0;
do
{
sum = sum + i;
Console.WriteLine("i等于" + i + "时sum为" + sum + "。");
i = i + 2;
} while (i <= 100);
Console.WriteLine("1-10的偶数之和为" + sum);
Console.ReadKey();
}
for 得奇偶数
static void Main(string[] args)
{
int[] array = { 4, 6, 7, 8, 9, 12, 13, 15 };
int total = 0;
int total1 = 0;
Console.WriteLine("偶数：");
for (int i = 0; i < array.Length; i++)
{
if (array[i] % 2 == 0)
{
total++;
Console.Write("{0}，", array[i]);
continue;
}
}
Console.WriteLine("\n奇数：");
for (int i = 0; i < array.Length; i++)
{
if (array[i] % 2 != 0)
{
total1++;
Console.Write("{0}，", array[i]);
continue;
}
}
Console.WriteLine("\n偶数总数为{0}", total);
Console.WriteLine("奇数总数为{0}", total1);
Console.ReadKey();
}
for 打印菱形
static void Main(string[] args)
{
//int blank; //空格
Console.WriteLine("输入菱形");
int total=int.Parse(Console.ReadLine());
for (int i = 1; i <= total; i++)
{ //空格
for (int j = total - i; j >= 1; j--)
{
Console.Write(" ");
}
//数字
for (int j = 0; j < 2 * i - 1; j++)
{
Console.Write("*");
}
Console.WriteLine();
}
for (int i = total-1; i >= 1; i--)
{ //空格
for (int j = total - i; j >= 1; j--)
{
Console.Write(" ");
}
//数字
for (int j = 0; j < 2 * i - 1; j++)
{
Console.Write("*");
}
Console.WriteLine();
}
Console.ReadKey();
}
if 判断大小写字母
class Program
{
static void Main(string[] args)
{
Console.WriteLine("请输入一个字母");
char ch = (char)Console.Read();
if(ch >='A' && ch <='Z')
{
Console.WriteLine("你输入的为大写字母");
}
else if (ch >='a' && ch <= 'z')
{ Console.WriteLine("你输入的为小写字母"); }
else {
Console.WriteLine("你输入的不是字母");
}
Console.ReadKey();
}
}
if 只能输1-2
class Program
{
static void Main(string[] args)
{
int i = ReadInt(1, 2);
Console.WriteLine(i);
if (i == 1)
{
Console.WriteLine("1dd");
}
if (i == 2)
{
Console.WriteLine("2dd");
}
else { Console.WriteLine("重新输入"); }
Console.ReadKey();
}
static int ReadInt(int min, int max)
{
while (true)
{
int number = Convert.ToInt32(Console.ReadLine());
if (number <min || number > max)
{
Console.WriteLine("只能输入{0}-{1}之间的数字", min, max);
}
return number;
}
}
}
练习
class Program
{
static void Main(string[] args)
{
//username();
message();
}
private static void message()
{
Console.WriteLine("Myshopping管理系统>客户信息管理>添加客户信息");
Console.WriteLine("情输入会员号（只能是4位）：");
double member = Convert.ToInt32(Console.ReadLine());
for (int i = 7; i > 0; i--)
{
if (member > 999 && member < 9999)
{
Console.WriteLine("情输入会员生日（月/日《用两位整数表示》）：");
string birthday = Console.ReadLine();
Console.WriteLine("情输入会员积分：");
double integral = Convert.ToInt32(Console.ReadLine());
Console.WriteLine("您输入的会员信息{0}，{1}，{2}", member, birthday, integral);
}
else
{
Console.WriteLine("输入错误，情重新输入");
Console.WriteLine("你还有的次数"+i);
member = Convert.ToInt32(Console.ReadLine());
continue;
}
}
Console.ReadKey();
}
public static void username()
{
string username = "username";
string pwd = "admin";
string user;
for (int i = 2; i >= 0; i--)
{
Console.WriteLine("请输入账户");
user = Console.ReadLine();
string pw;
Console.WriteLine("请输入密码");
pw = Console.ReadLine();
if (username.Equals(user) || pwd.Equals(pw))
{
Console.WriteLine("欢迎登入shopping系统");
}
else
{
Console.WriteLine("你还有"+i+"机会");
continue;
}
}
Console.WriteLine("对不起你3次都输入错误了，30分钟后在登入吧！");
Console.ReadKey();
}
}
