pygametimerandom
pygame.sprite Sprite

SCREEN_WIDTH = SCREEN_HEIGHT = BG_COLOR = pygame.Color()
TEXT_COLOR = pygame.Color()


BaseItem(Sprite):
    ():
        pygame.sprite.Sprite.()


MainGame():
    window = my_tank = enemyTankList = []
    enemyTankCount = myBulletList = []
    enemyBulletList = []
    explodeList = []

    ():
        ():
        pygame.display.init()
        MainGame.window = pygame.display.set_mode([SCREEN_WIDTHSCREEN_HEIGHT])
        MainGame.my_tank = Tank()
        .createEnemyTank()
        pygame.display.set_caption()
        :
            time.sleep()
            MainGame.window.fill(BG_COLOR)
            .getEvent()
            MainGame.window.blit(.getTextSuface(% (MainGame.enemyTankList))())

            MainGame.my_tank MainGame.my_tank.live:
                MainGame.my_tank.displayTank()
            :
                MainGame.my_tank
                MainGame.my_tank = .blitEnemyTank()
            .blitMyBullet()
            .blitEnemyBullet()
            .blitExplode()
            MainGame.my_tank MainGame.my_tank.live:
                MainGame.my_tank.stop:
                    MainGame.my_tank.move()
                pygame.display.update()

    ():
        top = i (MainGame.enemyTankCount):
            left = random.randint()
            speed = random.randint()
            enemy = EnemyTank(lefttopspeed)
            MainGame.enemyTankList.append(enemy)

    ():
        enemyTank MainGame.enemyTankList:
            enemyTank.live:
                enemyTank.displayTank()
                enemyTank.randMove()
                enemyBullet = enemyTank.shot()
                enemyBullet:
                    MainGame.enemyBulletList.append(enemyBullet)
            :  MainGame.enemyTankList.remove(enemyTank)

    ():
        myBullet MainGame.myBulletList:
            myBullet.live:
                myBullet.displayBullet()
                myBullet.move()
                myBullet.myBullet_hit_enemyTank()
            :
                MainGame.myBulletList.remove(myBullet)

    ():
        enemyBullet MainGame.enemyBulletList:
            enemyBullet.live:
                enemyBullet.displayBullet()
                enemyBullet.move()
                enemyBullet.enemyBullet_hit_myTank()
            :
                MainGame.enemyBulletList.remove(enemyBullet)

    ():
        explode MainGame.explodeList:
            explode.live:
                explode.displayExplode()
            :
                MainGame.explodeList.remove(explode)


    ():
        ()
        ()

    (text):
        pygame.font.init()
        font = pygame.font.SysFont()
        textSuface = font.render(textTEXT_COLOR)
        textSuface

    ():
        eventList = pygame.event.get()
        event eventList:
            event.type == pygame.QUIT:
                .endGame()
            event.type == pygame.KEYDOWN:
                MainGame.my_tank MainGame.my_tank.live:
                    event.key == pygame.K_LEFT:
                        MainGame.my_tank.direction = MainGame.my_tank.stop = ()
                    event.key == pygame.K_RIGHT:
                        MainGame.my_tank.direction = MainGame.my_tank.stop = ()
                    event.key == pygame.K_UP:
                        MainGame.my_tank.direction = MainGame.my_tank.stop = ()
                    event.key == pygame.K_DOWN:
                        MainGame.my_tank.direction = MainGame.my_tank.stop = ()
                    event.key == pygame.K_SPACE:
                        ()
                        (MainGame.myBulletList) < :
                            myBullet = Bullet(MainGame.my_tank)
                            MainGame.myBulletList.append(myBullet)

            event.type == pygame.KEYUP:
                event.key == pygame.K_UP event.key == pygame.K_DOWN event.key == pygame.K_RIGHT event.key == pygame.K_LEFT:
                    MainGame.my_tank MainGame.my_tank.live:
                        MainGame.my_tank.stop = Tank(Sprite):
    (lefttop):
        .images = {
            : pygame.image.load(): pygame.image.load(): pygame.image.load(): pygame.image.load()}
        .direction = .image = .images[.direction]
        .rect = .image.get_rect()
        .rect.left = left
        .rect.top = top
        .speed = .stop = .live = ():
        .direction == :
            .rect.left > :
                .rect.left -= .speed
        .direction == :
            .rect.left + .rect.height < SCREEN_WIDTH:
                .rect.left += .speed
        .direction == :
            .rect.top > :
                .rect.top -= .speed
        .direction == :
            .rect.top + .rect.height < SCREEN_HEIGHT:
                .rect.top += .speed

    ():
        Bullet()

    ():
        .image = .images[.direction]
        MainGame.window.blit(.image.rect)


MyTank(Tank):
    ():
        EnemyTank(Tank):
    (lefttopspeed):
        (EnemyTank).(lefttop)
        .images = {
            : pygame.image.load(): pygame.image.load(): pygame.image.load(): pygame.image.load()}
        .direction = .randDirection()
        .image = .images[.direction]
        .rect = .image.get_rect()
        .rect.left = left
        .rect.top = top
        .speed = speed
        .flag = .step = ():
        num = random.randint()
        num == :
            num == :
            num == :
            num == :
            ():
        .step <= :
            .direction = .randDirection()
            .step = :
            .move()
            .step -= ():
        num = random.randint()
        num < :
            Bullet()


Bullet(Sprite):
    (Tank):
        .image = pygame.image.load()
        .direction = Tank.direction
        .rect = .image.get_rect()
        .direction == :
            .rect.left = Tank.rect.left + Tank.rect.width / - .rect.width / .rect.top = Tank.rect.top - .rect.height
        .direction == :
            .rect.left = Tank.rect.left + Tank.rect.width / - .rect.width / .rect.top = Tank.rect.top + Tank.rect.height
        .direction == :
            .rect.left = Tank.rect.left - .rect.height
            .rect.top = Tank.rect.top + Tank.rect.width / - .rect.height / .direction == :
            .rect.left = Tank.rect.left + Tank.rect.height
            .rect.top = Tank.rect.top + Tank.rect.height / - .rect.height / .speed = .live = ():
        .direction == :
            .rect.top > :
                .rect.top -= .speed
            :
                .live = .direction == :
            .rect.top + .rect.height < SCREEN_HEIGHT:
                .rect.top += .speed
            :
                .live = .direction == :
            .rect.left > :
                .rect.left -= .speed
            :
                .live = .direction == :
            .rect.left + .rect.width < SCREEN_WIDTH:
                .rect.left += .speed
            :
                .live = ():
        MainGame.window.blit(.image.rect)

    ():
        enemyTank MainGame.enemyTankList:
            pygame.sprite.collide_rect(enemyTank):
                enemyTank.live = .live = explode = Explode(enemyTank)
                MainGame.explodeList.append(explode)
    ():
        MainGame.my_tank MainGame.my_tank.live:
            pygame.sprite.collide_rect(MainGame.my_tank):
                explode = Explode(MainGame.my_tank)
                MainGame.explodeList.append(explode)
                .live = MainGame.my_tank.live = Wall():
    ():
        ():
        Explode():
    (tank):
        .rect = tank.rect
        .images = [
            pygame.image.load()pygame.image.load()pygame.image.load()pygame.image.load()pygame.image.load()]
        .step = .image = .images[.step]
        .live = ():
        .step < (.images):
            .image = .images[.step]
            .step += MainGame.window.blit(.image.rect)
        :
            .live = .step = Music():
    ():
        ():
        __name__ == :
    MainGame().startGame()

老师  为啥我写完后敌方子弹碰到我方坦克后整个画面就卡住不动了呢，也不报错

s="爱你一百遍" 
ss=s*100
print(ss)
#100次循环打印
for i in range(100):
    print("第%d 次%s"%((i+1),s))

老师 如上面的代码中 print("第%d 次%s"%((i+1),s))1、代码里的%d和%s的作用是干嘛的？？能不能解释一下这句代码

2、"第%d 次%s"% 字符串后面怎么还加一个%？

老师,idea怎么找不到相对路径，自己在网上找了一些资料也没搞明白

public class TestVariable {

public static void main(String[] args){

int age=18;

int b; //只是声明了变量b，没有初始化；

int x=0,y=0,z=1;

System.out.println(age);

b = 0;   //使用之前，必须初始化！

System.out.println(b);

System.out.println(z);

}

}

老师这是我写的代码，然后显示的提示的是这样

错误: 仅当显式请求注释处理时才接受类名称 'TestVariable'

1 个错误

E:\mycode>

tkinter *
tkinter messagebox

root= Tk()
btn01 = Button(root)
btn01[]=btn01.pack()
songhua():
    messagebox.showinfo(,)
    ()

btn01.bind(,songhua)
root.mainloop()

老师，搞了好多天，实在是搞不定了，麻烦能帮忙看一下吗？这个问题真的困扰我太久了。如下图报错

一直提示拒绝连接，我网上查说是端口没有开启，我把端口全部开启了，也不行，一直报这个，换了其它端口也不行，已经实在是没有办法了啊，求求老师帮忙解决一下啊。

在bean标签什么时候id属性需要，什么时候不需要

老师，我想问一下当线程池里面有1个以上的线程同时运行时，这里Runnable任务的运行结果的顺序是不是就肯定不能保证。有没有方法可以让运行速度变快，又能让结果是按顺序显示的。

老师，centos7在安装ftp的时候，yum install -y vsftpd出现图中的报错，有什么解决办法吗？百度了半天也没有解决，求教

老师，我在hbuilder中打开的时候，出现了一张有照片，一张没有照片，出现照片的是相对路径的照片。

而在复制粘贴之后到桌面上的HTML打开的是绝对路径的显示照片，而相对路径不显示。

以下是代码：

<!DOCTYPE html>

<html>

<head>

<meta charset="utf-8">

<title></title>

</head>

<body>

<!--相对路径-->

<img src="img/2.jpg" />

<!--绝对路径-->

<img src="F:\\百战网页编程与设计\\项目\\01HTML\\img\\1.jpg" />

<!--网络路径-->

<img src="https://www.baidu.com/img/PCtm_d9c8750bed0b3c7d089fa7d55720d6cf.png" />

<p>

6666

<a href="#">

<img src="img/2.jpg" title="图片2" width="200px" height="100px" border="2px" alt="图片显示错误" align="center" />

</a>

8888

</p>

</body>

</html>

就很奇怪，望能解答，谢谢。

这个是什么原因？

老师为什么下面这个类不加static上面的创建对面就会报错，这是为什么

老师我代码应该没有写错呀，但是为什么还是会报错呢？

package com.bjsxt.network_programming;

import java.io.*;
import java.net.URL;

public class TestURL2 {
    public static void main(String[] args) throws IOException {
        /**
         * 网络爬虫
         * （1）从网络上获取资源www.baidu.com
         * （2）存储到本地
         */
//创建URL对象
        URL url=new URL("https://www.baifu.com/");//主页资源

        //获取字节流
        InputStream is=url.openStream();
        //缓存流
        BufferedReader br=new BufferedReader(new InputStreamReader(is,"utf-8"));
        //存储到本地
        BufferedWriter bw=new BufferedWriter(new OutputStreamWriter(new FileOutputStream("index.html"),"utf-8"));
        //边读边写
        String line =null;
        while ((line=br.readLine())!=null){
            bw.write(line);
            bw.newLine();
            bw.flush();
        }
        //关闭流

        bw.close();
        br.close();

    }
}

Exception in thread "main" java.net.ConnectException: Connection timed out: connect

at java.net.DualStackPlainSocketImpl.connect0(Native Method)

at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:79)

at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)

at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)

at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)

at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172)

at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)

at java.net.Socket.connect(Socket.java:589)

at sun.security.ssl.SSLSocketImpl.connect(SSLSocketImpl.java:666)

at sun.security.ssl.BaseSSLSocketImpl.connect(BaseSSLSocketImpl.java:173)

at sun.net.NetworkClient.doConnect(NetworkClient.java:180)

at sun.net.www.http.HttpClient.openServer(HttpClient.java:463)

at sun.net.www.http.HttpClient.openServer(HttpClient.java:558)

at sun.net.www.protocol.https.HttpsClient.<init>(HttpsClient.java:264)

at sun.net.www.protocol.https.HttpsClient.New(HttpsClient.java:367)

at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(AbstractDelegateHttpsURLConnection.java:191)

at sun.net.www.protocol.http.HttpURLConnection.plainConnect0(HttpURLConnection.java:1156)

at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:1050)

at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:177)

at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1564)

at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1492)

at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:263)

at java.net.URL.openStream(URL.java:1045)

at com.bjsxt.network_programming.TestURL2.main(TestURL2.java:17)

Process finished with exit code 1

老师好，这里的str1和str2难道不是String类型的变量吗？

为什么他们可以像对象一样去调用equals这个方法呢

try catch 和抛出异常的疑问：

以下2段代码，都能往磁盘写文件，在处理异常时，用try catch和抛出异常都能正常写文件，2者在用法上有什么规则或者要求吗？抛出异常感觉代码会更简洁，

import java.io.FileWriter;
import java.io.IOException;
public class TestFileWrite2 {
    public static void main(String[] args) throws IOException {
        FileWriter writer=new FileWriter("G:\\test5.txt");
        writer.write("hello,python");
        if(writer!=null) {
            writer.close();
        }
    }
}

-------------------

import java.io.IOException;
public class TestFileWriter {
    public static void main(String[] args) {
        //创建对象
        FileWriter writer=null;
        try {
            writer=new FileWriter("G:\\test2.txt");
            //写数据
            writer.write("hello,java");//写到的是缓冲区，不关闭不会写到文件里
            // writer.flush();
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            //
            try {
                if(writer!=null)
                writer.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
}