C# C# 语法

[Yann]

1.变量声明和使用：

string name = "John";
int age = 25;
Console.WriteLine("My name is {0} and I am {1} years old.", name, age);

2.条件语句（if-else）：

int score = 85;
if (score >= 60)
{
Console.WriteLine("You passed the exam!");
}
else
{
Console.WriteLine("You failed the exam.");
}

3.循环语句（for）：

for (int i = 1; i <= 5; i++)
{
Console.WriteLine("Number: {0}", i);
}

4.数组声明和访问：

string[] fruits = { "apple", "banana", "orange" };
Console.WriteLine(fruits[0]); // 输出 "apple"

5.方法声明和调用：

void Greet(string name)
{
Console.WriteLine("Hello, {0}!", name);
}

Greet("Alice"); // 输出 "Hello, Alice!"

6.类声明和实例化：

class Person
{
private string name;

public Person(string name)
    {
 this.name = name;
    }

public void Greet()
    {
Console.WriteLine("Hello, my name is {0}!", name);
    }
}

Person person = new Person("John");
person.Greet(); // 输出 "Hello, my name is John!"

7.文件导入和命名空间使用：

// 文件1.cs
public class MyClass
{
public string Variable = "Hello from file 1!";
}

// 文件2.cs
using System;
using YourNamespace;

class Program
{
static void Main()
    {
MyClass myObject = new MyClass();
Console.WriteLine(myObject.Variable); // 输出 "Hello from file 1!"
    }
}

8.异常处理：

public double Divide(int numerator, int denominator)
{
if (denominator == 0)
    {
throw new Exception("Division by zero error!");
    }
return (double)numerator / denominator;
}

try
{
Console.WriteLine(Divide(10, 0));
}
catch (Exception e)
{
Console.WriteLine("Error: " + e.Message);
}