有效沟通问答-【官方】百战程序员_IT在线教育培训机构

# coding=utf-8
# 结合异常机制finally确保关闭文件对象

try:
    f = open(r"E:\python\IO文件\a.txt", "a")
    s = "好好学Python\n"
    f.write(s)

except BaseException as e:
    print(e)
finally:
    f.close()

运行结果：

代码：

# coding=utf-8
# 结合异常机制finally确保关闭文件对象

try:
    f = open(r"E:\python\IO文件\a.txt", "a",encoding="utf-8")
    s = "好好学Python\n"
    f.write(s)

except BaseException as e:
    print(e)
finally:
    f.close()

运行结果：

问题：

为什么加了encoding="utf-8"之后还出现乱码了呢，我在网上搜了之后没有搜到，麻烦老师了

Python 全系列/第二阶段：Python 深入与提高/文件处理 31868楼

为啥我这个只是两个位置互换了，没有向视频那明显的抢占，什么情况，是win10系统优化了吗？？？

JAVA 全系列/第二阶段：JAVA 基础深化和提高/多线程技术（旧） 31869楼

cf 命令打不开f盘里的文件夹，这个怎么解决啊

JAVA 全系列/第一阶段：JAVA 快速入门/JAVA入门和背景知识 31870楼

老师，为啥反序列化时候是一条一条的进行呢，而不是b = pickle.load(f),将所有的内容反序列化过来。

Python 全系列/第二阶段：Python 深入与提高/文件处理 31871楼

为什么没有出现登录界面,代码没有报错

from tkinter import *
from tkinter import messagebox

class Application(Frame):
    def __init__(self,master=None):
        super().__init__(master)     #super()代表的是父类的定义,而不是父类的对象
        self.master=master
        self.pack()
        self.createWidget()
    def createWidget(self):
        '''创建登陆界面的组件'''
        self.label01=Label(self, text="用户名")
        self.label01.pack()

        #StringVar变量绑定到指点的组件.
        #StringVar变量的值发生变化,组件内容也变化;
        #组件内容发生变化,SringVar变量的值也发生变化
        v1=StringVar()
        self.entry01=Entry(self,textvariable=v1)
        self.entry01.pack()
        v1.set("admin")
        print(v1.get());print(self.entry01.get())



        #创建密码框
        self.label02 = Label(self, text="密码")
        self.label02.pack()


        v2 = StringVar()
        self.entry02 = Entry(self, textvariable=v2,show="*")
        self.entry02.pack()

        Button(self,text="登录",comman=self.login).pack()
    def login(self):
        username=self.entry01.get()
        pwd=self.entry02.get()
        print("去数据库比对用户名和密码")
        print("用户名:"+username)
        print("密码:" + pwd)
        if username=="gaoqi" and pwd=="123456":
             messagebox.showinfo("尚学堂学习系统","登陆成功!欢迎开始学习!")
        else:
              messagebox.showinfo("尚学堂学习系统","登陆失败!重新登录!")
if __name__=='main__':
    root=Tk()
    root.geometry("400x120+200+300")
    app=Application(master=root)
    root.mainloop()

Python 全系列/第二阶段：Python 深入与提高/GUI编程（隐藏） 31872楼

老师，这可咋整，我连续配了两个版本的linux都不行，第一次我以为是版本问题，换了第二个版本的还是不行，我配置的没错呀，有data，有myid，zoo.cfg里的路径，监听端口，还有创建集群的那三句话，还有我自己的IP地址都没错呀，我还特地在没配置myid跟那三句集群的话之前把我配置的三个zookeeper01-03都启动了一遍，都可以，没问题，可是一配置集群就宕机了，我也找不到问题出在哪里

JAVA 全系列/第十一阶段：分布式RPC调用和分布式文件存储/Zookeeper 31873楼

"""开发记事本软件的菜单"""

from tkinter.filedialog import *
from tkinter.colorchooser import *


class Application(Frame):

    def __init__(self, master=None):
        super().__init__(master)        # super()代表的是父类的定义，而不是父类对象
        self.master = master
        self.textpad = None             # textpad表示Text文本框对象
        self.pack()
        self.createWidget()

    def createWidget(self):
        # 创建主菜单栏
        menubar = Menu(root)

        # 创建子菜单
        menuFile = Menu(menubar)
        menuEdit = Menu(menubar)
        menuHelp = Menu(menubar)

        # 将子菜单加入主菜单栏
        menubar.add_cascade(label='文件(F)', menu=menuFile)
        menubar.add_cascade(label='编辑(E)', menu=menuEdit)
        menubar.add_cascade(label='帮助(H)', menu=menuHelp)

        # 添加菜单项
        menuFile.add_command(label='新建', accelerator='ctrl+n', command=self.test)
        menuFile.add_command(label='打开', accelerator='ctrl+o', command=self.openfile)
        menuFile.add_command(label='保存', accelerator='ctrl+s', command=self.test)
        menuFile.add_separator()  # 添加分割线
        menuFile.add_command(label='退出', accelerator='ctrl+q', command=self.test)

        # 将主菜单加到根窗口
        root['menu'] = menubar

        # 文本编辑区
        self.textpad = Text(root, width=65, height=30)
        self.textpad.pack()

        # 创建上下菜单
        self.contextMenu = Menu(root)
        self.contextMenu.add_command(label='背景颜色', command=self.test)

        # 右键绑定事件
        root.bind('<Button-3>', self.createContextMenu)

    def openfile(self):
        self.textpad.delete("1.0", "end")  # 把text控件中所有的内容清空
        with askopenfile(title="打开文本文件") as f:
            self.textpad.insert(INSERT, f.read())
            self.filename = f.name
        # try:
        #     # 以utf-8编码打开
        #     with open(askopenfilename()) as f:
        #         self.textpad.insert(INSERT, f.read())
        #         self.filename = f.name
        #         print(f.read())
        # except UnicodeDecodeError:
        #     # 以GBK编码打开
        #     with open(askopenfilename()) as f:
        #         print(f.read())

    def test(self):
        pass

    def createContextMenu(self, event):
        self.contextMenu.post(event.x_root, event.y_root)


if __name__ == '__main__':
    root = Tk()
    root.geometry("450x300+200+300")
    root.title("百战程序员的简易记事本")
    app = Application(master=root)
    root.mainloop()

老师在选择本地文件之后，报这个错误，请问是什么原因？

Python 全系列/第二阶段：Python 深入与提高/GUI编程（隐藏） 31874楼

问题：老师我用c3p0数据库连接池用配置文件实现连接时报错了，你看是我这个xml文件建的有问题吗，还是c3p0-0.9.1.2.jar这个版本还需要依赖别的jar包，下面是报的错，最下面是配置文件图片

六月 19, 2020 10:37:26 上午 com.mchange.v2.log.MLog <clinit>

信息: MLog clients using java 1.4+ standard logging.

六月 19, 2020 10:37:27 上午 com.mchange.v2.c3p0.C3P0Registry banner

信息: Initializing c3p0-0.9.1.2 [built 21-May-2007 15:04:56; debug? true; trace: 10]

六月 19, 2020 10:37:27 上午 com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource getPoolManager

信息: Initializing c3p0 pool... com.mchange.v2.c3p0.ComboPooledDataSource [ acquireIncrement -> 5, acquireRetryAttempts -> 30, acquireRetryDelay -> 1000, autoCommitOnClose -> false, automaticTestTable -> null, breakAfterAcquireFailure -> false, checkoutTimeout -> 0, connectionCustomizerClassName -> null, connectionTesterClassName -> com.mchange.v2.c3p0.impl.DefaultConnectionTester, dataSourceName -> hellc3p0, debugUnreturnedConnectionStackTraces -> false, description -> null, driverClass -> com.mysql.jdbc.Driver, factoryClassLocation -> null, forceIgnoreUnresolvedTransactions -> false, identityToken -> 1hge9eiaa1k63i3np8f2kz|e73f9ac, idleConnectionTestPeriod -> 0, initialPoolSize -> 10, jdbcUrl -> jdbc.mysql://localhost:3306/test, maxAdministrativeTaskTime -> 0, maxConnectionAge -> 0, maxIdleTime -> 0, maxIdleTimeExcessConnections -> 0, maxPoolSize -> 100, maxStatements -> 0, maxStatementsPerConnection -> 2, minPoolSize -> 10, numHelperThreads -> 3, numThreadsAwaitingCheckoutDefaultUser -> 0, preferredTestQuery -> null, properties -> {user=******, password=******}, propertyCycle -> 0, testConnectionOnCheckin -> false, testConnectionOnCheckout -> false, unreturnedConnectionTimeout -> 0, usesTraditionalReflectiveProxies -> false ]

六月 19, 2020 10:37:47 上午 com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector run

警告: com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector@1f407bb -- APPARENT DEADLOCK!!! Creating emergency threads for unassigned pending tasks!

六月 19, 2020 10:37:47 上午 com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector run

警告: com.mchange.v2.async.ThreadPoolAsynchronousRunner$DeadlockDetector@1f407bb -- APPARENT DEADLOCK!!! Complete Status:

Managed Threads: 3

Active Threads: 3

Active Tasks:

com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@4e0ee3ce (com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#0)

com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@6fe6fc6b (com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#1)

com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@7f0acc23 (com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#2)

Pending Tasks:

com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@17088d3d

com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@2e211c81

com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@767ca88a

com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@5fbe09b2

com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@c0c061d

com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@2a6fc609

com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@39440336

Pool thread stack traces:

Thread[com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#0,5,main]

java.lang.Thread.sleep(Native Method)

com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1805)

com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)

Thread[com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#1,5,main]

java.lang.Thread.sleep(Native Method)

com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1805)

com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)

Thread[com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#2,5,main]

java.lang.Thread.sleep(Native Method)

com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1805)

com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)

六月 19, 2020 10:37:56 上午 com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask run

警告: com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@4e0ee3ce -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (30). Last acquisition attempt exception:

java.sql.SQLException: No suitable driver

at java.sql.DriverManager.getDriver(DriverManager.java:315)

at com.mchange.v2.c3p0.DriverManagerDataSource.driver(DriverManagerDataSource.java:223)

at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:134)

at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182)

at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171)

at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137)

at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014)

at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32)

at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810)

at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547)

六月 19, 2020 10:37:56 上午 com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask run

警告: com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@7f0acc23 -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (30). Last acquisition attempt exception: