C# 方法、函数的值如何传递

作者：vkvi 来源：ITPOW（原创）日期：2010-12-18

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

public partial class Param : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        C1 c1 = new C1();
        Response.Write(c1.P); // 1
        Change(c1);
        Response.Write(c1.P); // 2
        Change2(c1);
        Response.Write(c1.P); // 2，Change2 的 c1 = new C1(); 改变不了外界的 c1

        int m = 1;
        Response.Write(m); // 1
        Change(m);
        Response.Write(m); // 1
    }

    private void Change(C1 c1)
    {
        c1.P *= 2;
    }

    private void Change2(C1 c1)
    {
        c1 = new C1();
    }

    private void Change(int m)
    {
        m *= 2;
    }
}

public class C1
{
    public int P = 1;
}

注意，Change2 并改变不了外界的 c1。