class MyClass
{
    private int myVar;
    public void SetVar(int var)
    {
        this.myVar = var; // 使用 this 關鍵字引用當前對象的成員變量
    }
}

class MyClass
{
    private int myVar;
    public void SetVar(int myVar)
    {
        this.myVar = myVar; // 使用 this 關鍵字指定成員變量
    }
}

class MyClass
{
    private int myVar;
    public MyClass(int var)
    {
        this.myVar = var;
    }
    public MyClass() : this(0) // 調(diào)用另一個構造函數(shù)
    {
    }
}

class MyClass
{
    public void Method()
    {
        AnotherClass.DoSomething(this); // 將當前對象傳遞給另一個方法
    }
}

using System;
public static class StringExtensions
{
    public static int WordCount(this string str)
    {
        return str.Split(new char[] { ' ', '.', '?' }, StringSplitOptions.RemoveEmptyEntries).Length;
    }
}
class Program
{
    static void Main()
    {
        string sentence = "Hello, world! This is a sentence.";
        int wordCount = sentence.WordCount();
        Console.WriteLine($"The sentence has {wordCount} words.");
    }
}