C#关于多线程及线程同步|C#关于多线程及线程同步 lock锁的应用 C#关于多线程及线程同步lock锁

Form1.cs

using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Threading; using System.Threading.Tasks; using System.Windows.Forms; namespace WinLock { public partial class Form1 : Form { public Form1() { InitializeComponent(); }private void btn_Start_Click(object sender, EventArgs e) { listBox1.Items.Clear(); Thread[] threads = new Thread[10]; //使用new关键字在堆里创建对象，其生命期相当于全局变量，但访问的时候与普通变量一样 Account acc = new Account(1000, this); for (int i = 0; i < 10; i++) { Thread t = new Thread(acc.DoTransactions); t.Name = "线程" + i; threads[i] = t; } for (int i = 0; i < 10; i++) { threads[i].Start(); } }delegate void AddListBoxItemDelegate(string str); //在类的内部也能声明代理 public void AddListBoxItem(string str) { if (listBox1.InvokeRequired)//如果是跨线程访问控件则为true { AddListBoxItemDelegate d = AddListBoxItem; //代理 listBox1.Invoke(d, str); //调用代理函数并传递参数 } else { listBox1.Items.Add(str); //不是跨线程访问控件则直接访问该控件 } } } }

account.cs

using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Threading; using System.Threading.Tasks; namespace WinLock { public class Account { private Object lockedObj = new Object(); int balance; Random r = new Random(); Form1 form1; public Account(int initial, Form1 form1) { this.form1 = form1; this.balance = initial; } /// /// 取款 /// /// 取款金额 /// 余额 private int Withdraw(int amount) { if (balance < 0) { form1.AddListBoxItem("余额：" + balance + " 已经为负值了，还想取呵！"); }//将lock (lockedObj)这句注释掉，看看会发生什么情况 lock (lockedObj) { if (balance >= amount) { string str = Thread.CurrentThread.Name + "取款---"; str += string.Format("取款前余额：{0,-6}取款：{1,-6}", balance, amount); balance = balance - amount; str += "取款后余额：" + balance; form1.AddListBoxItem(str); return amount; } else { return 0; } } } /// 自动取款 public void DoTransactions()//Transaction--事务 { for (int i = 0; i < 100; i++) { Withdraw(r.Next(1, 100)); } }} }

不加lock 会出现统一资源被多次利用的情况
【C#关于多线程及线程同步|C#关于多线程及线程同步 lock锁的应用】