老师，我这编译了image还是报错

报错提示：字符串不能转换为浮点型。这点我理解。但是当我找到课件中讲到的同一个程序并没有报错，发现区别仅有以下：我的代码提前定义了类型赋了一个空的字符串值。老师的代码中变量s没有一开始定义和赋值，而是在input中自动有了数据类型为字符串型。不理解老师的代码中if float（s）同样也是字符串转浮点型，为什么没报错？？

我的代码如下：

#需要用到的变量初始赋值
salary_sum = 0.0
salary_eve = 0.0
salarys = []
salary ="" #临时变量，中间变量,用于存储每次输入的薪资值
while True:
    salary = input("请输入薪资，按Q或q完成全部输入")
    if salary.upper() == "Q":
        print("完成全部薪资输入,退出")
        break
    elif float(salary) < 0:
        continue
    else:
        salarys.append(float(salary))
#统计并处理打印信息
num = len(salarys)
for a in salarys:
    salary_sum += float(a)
salary_eve = salary_sum / num
print("员工数{0}".format(num))
print("录入的薪资为{0}".format(salarys))
print("平均薪资为{0}".format(salary_eve))

报错提示截图如下：

老师的代码课件中如下：

老师，在调用这个函数时，为什么不能单独调第一个打印，

通过self传入类属性,不可以使用

Student.nrm()

这个n-1和*4是什么，能详细说明一下吗？

这里凭什么可以实现接口啊, 两个项目没有任何关联, 只是跟父工程添加了依赖, 

我的就一点都不行,

没有erlang安装包，rabbitmq那一章节也没有erlang安装包

老师，new  后面的可以看做 调用这个类，   s.()这个点 后面的可以看做是使用这个方法输出什么，是这样吗？

老师我觉得我这个项目写崩了有点。。。后台管理系统突然登录不进去了，，我这边没改什么东西啊。。下面试AdminServiceApplication报的异常信息

2020-12-07 02:15:24.452  INFO 3563 --- [nio-8080-exec-1] c.b.service.impl.SysLoginServiceImpl     : 用户admin开始登录

2020-12-07 02:15:24.610  INFO 3563 --- [nio-8080-exec-1] c.netflix.config.ChainedDynamicProperty  : Flipping property: authorization-server.ribbon.ActiveConnectionsLimit to use NEXT property: niws.loadbalancer.availabilityFilteringRule.activeConnectionsLimit = 2147483647

2020-12-07 02:15:24.623  INFO 3563 --- [nio-8080-exec-1] c.netflix.loadbalancer.BaseLoadBalancer  : Client: authorization-server instantiated a LoadBalancer: DynamicServerListLoadBalancer:{NFLoadBalancer:name=authorization-server,current list of Servers=[],Load balancer stats=Zone stats: {},Server stats: []}ServerList:null

2020-12-07 02:15:24.628  INFO 3563 --- [nio-8080-exec-1] c.n.l.DynamicServerListLoadBalancer      : Using serverListUpdater PollingServerListUpdater

2020-12-07 02:15:24.680  INFO 3563 --- [nio-8080-exec-1] com.alibaba.nacos.client.naming          : new ips(1) service: DEFAULT_GROUP@@authorization-server -> [{"clusterName":"DEFAULT","enabled":true,"ephemeral":true,"healthy":true,"instanceHeartBeatInterval":5000,"instanceHeartBeatTimeOut":15000,"instanceId":"192.168.86.147#9999#DEFAULT#DEFAULT_GROUP@@authorization-server","ip":"192.168.86.147","ipDeleteTimeout":30000,"metadata":{"preserved.register.source":"SPRING_CLOUD"},"port":9999,"serviceName":"DEFAULT_GROUP@@authorization-server","weight":1.0}]

2020-12-07 02:15:24.685  INFO 3563 --- [nio-8080-exec-1] com.alibaba.nacos.client.naming          : current ips:(1) service: DEFAULT_GROUP@@authorization-server -> [{"clusterName":"DEFAULT","enabled":true,"ephemeral":true,"healthy":true,"instanceHeartBeatInterval":5000,"instanceHeartBeatTimeOut":15000,"instanceId":"192.168.86.147#9999#DEFAULT#DEFAULT_GROUP@@authorization-server","ip":"192.168.86.147","ipDeleteTimeout":30000,"metadata":{"preserved.register.source":"SPRING_CLOUD"},"port":9999,"serviceName":"DEFAULT_GROUP@@authorization-server","weight":1.0}]

2020-12-07 02:15:24.694  INFO 3563 --- [nio-8080-exec-1] c.netflix.config.ChainedDynamicProperty  : Flipping property: authorization-server.ribbon.ActiveConnectionsLimit to use NEXT property: niws.loadbalancer.availabilityFilteringRule.activeConnectionsLimit = 2147483647

2020-12-07 02:15:24.696  INFO 3563 --- [nio-8080-exec-1] c.n.l.DynamicServerListLoadBalancer      : DynamicServerListLoadBalancer for client authorization-server initialized: DynamicServerListLoadBalancer:{NFLoadBalancer:name=authorization-server,current list of Servers=[192.168.86.147:9999],Load balancer stats=Zone stats: {unknown=[Zone:unknown; Instance count:1; Active connections count: 0; Circuit breaker tripped count: 0; Active connections per server: 0.0;]

},Server stats: [[Server:192.168.86.147:9999; Zone:UNKNOWN; Total Requests:0; Successive connection failure:0; Total blackout seconds:0; Last connection made:Wed Dec 31 16:00:00 PST 1969; First connection made: Wed Dec 31 16:00:00 PST 1969; Active Connections:0; total failure count in last (1000) msecs:0; average resp time:0.0; 90 percentile resp time:0.0; 95 percentile resp time:0.0; min resp time:0.0; max resp time:0.0; stddev resp time:0.0]

]}ServerList:com.alibaba.cloud.nacos.ribbon.NacosServerList@6c941ca1

2020-12-07 02:15:24.964 ERROR 3563 --- [nio-8080-exec-1] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is feign.FeignException$BadRequest: [400] during [POST] to [http://authorization-server/oauth/token?grant_type=password&username=admin&password=123456&login_type=admin_type] [OAuth2FeignClient#getToken(String,String,String,String,String)]: [{"error":"invalid_grant","error_description":"Bad credentials"}]] with root cause

feign.FeignException$BadRequest: [400] during [POST] to [http://authorization-server/oauth/token?grant_type=password&username=admin&password=123456&login_type=admin_type] [OAuth2FeignClient#getToken(String,String,String,String,String)]: [{"error":"invalid_grant","error_description":"Bad credentials"}]

at feign.FeignException.clientErrorStatus(FeignException.java:195) ~[feign-core-10.7.4.jar:na]

at feign.FeignException.errorStatus(FeignException.java:177) ~[feign-core-10.7.4.jar:na]

at feign.FeignException.errorStatus(FeignException.java:169) ~[feign-core-10.7.4.jar:na]

at feign.codec.ErrorDecoder$Default.decode(ErrorDecoder.java:92) ~[feign-core-10.7.4.jar:na]

at feign.SynchronousMethodHandler.executeAndDecode(SynchronousMethodHandler.java:156) ~[feign-core-10.7.4.jar:na]

at feign.SynchronousMethodHandler.invoke(SynchronousMethodHandler.java:80) ~[feign-core-10.7.4.jar:na]

at feign.ReflectiveFeign$FeignInvocationHandler.invoke(ReflectiveFeign.java:100) ~[feign-core-10.7.4.jar:na]

at com.sun.proxy.$Proxy140.getToken(Unknown Source) ~[na:na]

at com.bjsxt.service.impl.SysLoginServiceImpl.login(SysLoginServiceImpl.java:51) ~[classes/:na]

at com.bjsxt.controller.SysLoginController.login(SysLoginController.java:39) ~[classes/:na]

at com.bjsxt.controller.SysLoginController$$FastClassBySpringCGLIB$$75a59cd6.invoke(<generated>) ~[classes/:na]

at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218) ~[spring-core-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:771) ~[spring-aop-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) ~[spring-aop-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:749) ~[spring-aop-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed(MethodInvocationProceedingJoinPoint.java:100) ~[spring-aop-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at com.bjsxt.aspect.WebLogAspect.recodeWebLog(WebLogAspect.java:58) ~[classes/:na]

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_211]

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_211]

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_211]

at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_211]

at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs(AbstractAspectJAdvice.java:644) ~[spring-aop-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod(AbstractAspectJAdvice.java:633) ~[spring-aop-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.aop.aspectj.AspectJAroundAdvice.invoke(AspectJAroundAdvice.java:70) ~[spring-aop-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:749) ~[spring-aop-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:95) ~[spring-aop-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:749) ~[spring-aop-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:691) ~[spring-aop-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at com.bjsxt.controller.SysLoginController$$EnhancerBySpringCGLIB$$138d1ae8.login(<generated>) ~[classes/:na]

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_211]

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_211]

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_211]

at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_211]

at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190) ~[spring-web-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138) ~[spring-web-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:105) ~[spring-webmvc-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:879) ~[spring-webmvc-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:793) ~[spring-webmvc-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040) ~[spring-webmvc-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943) ~[spring-webmvc-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) ~[spring-webmvc-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:909) ~[spring-webmvc-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at javax.servlet.http.HttpServlet.service(HttpServlet.java:660) ~[tomcat-embed-core-9.0.35.jar:9.0.35]

at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) ~[spring-webmvc-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at javax.servlet.http.HttpServlet.service(HttpServlet.java:741) ~[tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-9.0.35.jar:9.0.35]

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.35.jar:9.0.35]

at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:320) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:126) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:90) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:118) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:111) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:158) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.oauth2.provider.authentication.OAuth2AuthenticationProcessingFilter.doFilter(OAuth2AuthenticationProcessingFilter.java:176) ~[spring-security-oauth2-2.3.4.RELEASE.jar:na]

at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:116) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.header.HeaderWriterFilter.doHeadersAfter(HeaderWriterFilter.java:92) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:77) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:105) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:56) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:215) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:178) ~[spring-security-web-5.3.2.RELEASE.jar:5.3.2.RELEASE]

at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:358) ~[spring-web-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:271) ~[spring-web-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.35.jar:9.0.35]

at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) ~[spring-web-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.35.jar:9.0.35]

at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) ~[spring-web-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.35.jar:9.0.35]

at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.doFilterInternal(WebMvcMetricsFilter.java:93) ~[spring-boot-actuator-2.3.0.RELEASE.jar:2.3.0.RELEASE]

at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.35.jar:9.0.35]

at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.6.RELEASE.jar:5.2.6.RELEASE]

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202) ~[tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541) [tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139) [tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) [tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) [tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) [tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:373) [tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) [tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868) [tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1590) [tomcat-embed-core-9.0.35.jar:9.0.35]

at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-9.0.35.jar:9.0.35]

at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_211]

at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_211]

at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-9.0.35.jar:9.0.35]

at java.lang.Thread.run(Thread.java:748) [na:1.8.0_211]

2020-12-07 02:15:25.634  INFO 3563 --- [erListUpdater-0] c.netflix.config.ChainedDynamicProperty  : Flipping property: authorization-server.ribbon.ActiveConnectionsLimit to use NEXT property: niws.loadbalancer.availabilityFilteringRule.activeConnectionsLimit = 2147483647

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>06php与MySQL增删改查</title>
    <script src="./jquery-3.6.0.min.js"></script>
</head>

<body>
    <form action="06php与MySQL增.php" method="post" id="insert">
        <span>账号：</span><input type="text" placeholder="请输入您的账号" name="insert-userName" id="userName">
        <span>密码：</span><input type="password" placeholder="请输入您的密码" name="insert-password" id="password">
        <span>电子邮箱：</span><input type="text" placeholder="请输入您的电子邮箱" name="insert-email" id="email">
        <button type="submit">增</button>
    </form>
    <form action="06php与MySQL删.php" method="post" id="delete">
        <span>id：</span><input type="text" placeholder="请输入您要删除的id号" name="delete-id" id="id">
        <button type="submit">删</button>
    </form>
    <form>
        <!-- 修改密码 -->
        <span>账号：</span><input type="text" placeholder="请输入您的账号" name="update-userName" id="update-userName">
        <span>修改后的密码：</span><input type="text" placeholder="请输入您修改后的密码" name="update-password" id="update-password">
        <button id="update-pwd-btn">提交改后的密码</button><span id="update-result"></span>
        <br>
        <!-- 按用户名查找 -->
        <span>查找的账号：</span><input type="text" placeholder="请输入您要查找的账号" name="select-userName" id="select-userName">
        <button id="select-btn">提交</button><span id="select-result"></span>
        <script>
            $("#update-pwd-btn").click(function() {
                var updateUserName = $("#update-userName").val();
                var updatePwd = $("#update-password").val();
                $.ajax({
                    type: 'get',
                    url: "http://localhost/php/06php与MySQL改.php",
                    data: {
                        userName: updateUserName,
                        password: updatePwd
                    },
                    success: function(res) {
                        //$("#update-result").html(res);
                        console.log("改操作成功！");
                    }
                })
            })

            $("#select-btn").click(function() {
                var selectUserName = $("#select-userName").val();
                $.ajax({
                    type: "post",
                    url: "http://localhost/php/06php与MySQL查.php",
                    data: {
                        userName: selectUserName
                    },
                    success: function(res) {
                        // $("#select-result").html(res);
                        console.log('查操作成功');
                    }
                })
            })
        </script>

    </form>
    <script>
    </script>
</body>

</html>

我给每一个增删改查都写了一个php文件，增和删没用ajax,可以跳转实现功能。但是用Ajax做的改查，数据库的数据是可以改，但是success对应的回调函数不执行。我把回调函数就写成console.log('查操作成功')也不可以。一打开控制台就会有报错：DevTools 无法加载来源映射：无法加载 chrome-extension://gighmmpiobklfepjocnamgkkbiglidom/browser-polyfill.js.map 的内容：系统错误: net::ERR_FILE_NOT_FOUND

下面是我写的查操作的php文件

<?php

    $userName=$_GET['userName'];

    $password=$_GET['password'];

    $con=mysqli_connect('localhost','root','','zirenqimysql');

    if($con){

        mysqli_query($con,"set names utf8");

        $sql="update `usertable` set password='$password' where userName='$userName'";

        $result=mysqli_query($con,$sql);

        mysqli_close($con);

        if($result>0){

            echo "改操作成功！";

        }else{

            echo "改操作失败！";

        }

    }else{

        echo "连接失败！";

    }

?>

我不知道为什么success对应的函数没有结果，控制台的报错要怎么改？

你好，准备好的模块没有办法上传至Pypi，报错信息如下。百度和Q&A并没有类似的报错信息可以参考。麻烦各位帮忙看看，谢谢了。

老师，这返回的东西是什么情况啊，还可以这么写？这个showimg是不是就是所绑定的url？

搭建maven项目时，pom.xml文件里添加的依赖出现红色字样？检查setting中的maven吗？

老师，我pycharm的版本是2020的，我按照课程的代码敲了，但是浏览器报错

from flask import Flask

app = Flask(__name__)


@app.route('/')
def hello_world():
    return 'Hello World!'

@app.route('/article/<id>/')
def list1(id):
    print(id)
    return '您请求的文章详情id为：%s' % id


if __name__ == '__main__':
    app.run()

老师，执行此代码的时候，next语句开始执行consumer方法，此时g生成器中应该还没有给n传递值，此时

print(f"生产了第{n}个产品")

这个语句是否执行了呢？为什么打印出来生产了第0个产品？

老师这个报错应该怎么改。我的表格一共三列