using System; namespace Lesson03 { class Program { static void Main(string[] args) { // ========== if / else ========== Console.WriteLine("=== if / else ==="); int score = 85; if (score >= 90) { Console.WriteLine("优秀"); } else if (score >= 60) { Console.WriteLine("及格"); } else { Console.WriteLine("不及格"); } // 三元运算符 string result = score >= 60 ? "及格" : "不及格"; Console.WriteLine($"三元运算: {result}"); // ========== switch ========== Console.WriteLine("\n=== switch ==="); int day = 3; switch (day) { case 1: Console.WriteLine("星期一"); break; case 2: Console.WriteLine("星期二"); break; case 3: Console.WriteLine("星期三"); break; default: Console.WriteLine("其他"); break; } // ========== for 循环 ========== Console.WriteLine("\n=== for 循环 ==="); for (int i = 0; i < 5; i++) { Console.WriteLine($"计数: {i}"); } // ========== foreach ========== Console.WriteLine("\n=== foreach 循环 ==="); string[] names = { "无言势", "VRChat", "字幕" }; foreach (string name in names) { Console.WriteLine(name); } // ========== while 循环 ========== Console.WriteLine("\n=== while 循环 ==="); int count = 0; while (count < 3) { Console.WriteLine($"while: {count}"); count++; } // ========== do while ========== Console.WriteLine("\n=== do while ==="); int n = 0; do { Console.WriteLine($"do while: {n}"); n++; } while (n < 3); // ========== break 和 continue ========== Console.WriteLine("\n=== break 和 continue ==="); for (int i = 0; i < 10; i++) { if (i == 3) continue; // 跳过 3 if (i == 7) break; // 退出循环 Console.WriteLine(i); } Console.ReadLine(); } } }