前言
本文主要使用spring boot + shiro + vue来实现前后端分离的认证登陆和权限管理,适合和我一样刚开始接触前后端完全分离项目的同学,但是你必须自己搭建过前端项目和后端项目,本文主要是介绍他们之间的互通,如果不知道这么搭建前端项目的同学可以先找别的blog看一下。
自己摸索了一下,可能会有一些问题,也有可能有更好的实现方式,但这个demo主要是用来记录自己搭建系统,独立完成前后端分离项目的过程,并且作为自己的毕业设计框架。所以有问题的话欢迎提出,共同交流。源码在github上,有需要的同学可以自己去取(地址在结尾)。
1.前端登陆页面输入http://localhost:8080/#/login会跳转到前端登陆界面,输入用户名密码后向后端 localhost:8888 发送验证请求
2.后台接受输入信息后,通过shiro认证,向前台返回认证结果,密码是通过md5加密的
3.登陆成功后,权限认证,有些页面只能管理员才能进入,有些按钮只能拥有某项权限的人才能看到,后台有些接口只能被有权限的人访问。
这么解决上面的问题?我这里的思路是(注*思路最重要,代码只会贴关键代码,全部代码请上git上取):
1.前端技术栈
框架:vue+elementui+axios
语言:es6,js
环境:node8 + yarn
打包工具: webpack
开发工具:vscode
2.后端
框架:spring Boot多模块+ maven + shiro + jpa + mysql8.0
开发工具:intellij idea
1.后端开发流程
·搭建spring boot多模块项目(本文不会介绍)
·创建shiro角色和权限的数据表
·集成shiro框架和md5加密
·开发登陆认证接口
2.前端开发流程
·搭建前端运行环境和webpack项目(本文不会介绍)
·开发登陆页面组件
·跨域——来支持请求后端接口
·路由开发,钩子函数(页面跳转控制),cookieUtil开发(存储后台roles和permissions信息),自定义指令(前端细粒度控制)
·启动项目,测试登陆及权限验证
1.创建shiro角色和权限的数据表
2.集成shiro框架和md5加密
<!-- shiro -->
<dependency>
<groupId>org.apache.shiro</groupId>
<artifactId>shiro-spring</artifactId>
<version>${
shiro.version}</version>
</dependency>
<dependency>
<groupId>org.apache.shiro</groupId>
<artifactId>shiro-core</artifactId>
<version>1.4.0</version>
<scope>compile</scope>
</dependency>
/**
* Created by WJ on 2019/3/28 0028
* 自定义权限匹配和密码匹配
*/
public class MyShiroRealm extends AuthorizingRealm {
@Resource
private SysRoleService sysRoleService;
@Resource
private UserRepository userRepository;
@Resource
private SysPermissionService sysPermissionService;
@Resource
private UserService userService;
@Override
public AuthorizationInfo doGetAuthorizationInfo(PrincipalCollection principals) {
System.out.println("权限配置-->MyShiroRealm.doGetAuthorizationInfo()");
SimpleAuthorizationInfo authorizationInfo = new SimpleAuthorizationInfo();
User User = (User) principals.getPrimaryPrincipal();
try {
List<SysRole> roles = sysRoleService.selectRoleByUserId(User.getId());
for (SysRole role : roles) {
authorizationInfo.addRole(role.getRole());//角色存储
}
//此处如果多个角色都拥有某项权限,bu会数据重复,内部用的是Set
List<SysPermission> sysPermissions = sysPermissionService.selectPermByRole(roles);
for (SysPermission perm : sysPermissions) {
authorizationInfo.addStringPermission(perm.getPermission());//权限存储
}
} catch (Exception e) {
e.printStackTrace();
}
return authorizationInfo;
}
/*主要是用来进行身份认证的,也就是说验证用户输入的账号和密码是否正确。*/
@Override
protected AuthenticationInfo doGetAuthenticationInfo(AuthenticationToken token) {
//获取用户的输入的账号.
String username = (String) token.getPrincipal();
// System.out.println(token.getCredentials());
//通过username从数据库中查找 User对象,如果找到,没找到.
//实际项目中,这里可以根据实际情况做缓存,如果不做,Shiro自己也是有时间间隔机制,2分钟内不会重复执行该方法
User user = userRepository.findByUsername(username).get();//*
if (user == null) {
return null;
}
if (user.getState() == 0) {
//账户冻结
throw new LockedAccountException();
}
SimpleAuthenticationInfo authenticationInfo = new SimpleAuthenticationInfo(
user, //用户名
user.getPassword(), //密码
ByteSource.Util.bytes(user.getCredentialsSalt()),//salt=username+salt
getName() //realm name
);
return authenticationInfo;
}
}
@Configuration
public class ShiroConfig
{
@Value("${sessionOutTime}")
private String serverSessionTimeout;
/**
* 密码校验规则HashedCredentialsMatcher,也就是密码比对器
* 这个类是为了对密码进行编码的 ,
* 防止密码在数据库里明码保存 , 当然在登陆认证的时候 ,
* 这个类也负责对form里输入的密码进行编码
* 处理认证匹配处理器:如果自定义需要实现继承HashedCredentialsMatcher
*/
@Bean("credentialsMatcher")
public HashedCredentialsMatcher hashedCredentialsMatcher() {
HashedCredentialsMatcher credentialsMatcher = new HashedCredentialsMatcher();
//指定加密方式为MD5
credentialsMatcher.setHashAlgorithmName("MD5");
//加密次数
credentialsMatcher.setHashIterations(1024);
credentialsMatcher.setStoredCredentialsHexEncoded(true);
return credentialsMatcher;
}
@Bean
public FilterRegistrationBean delegatingFilterProxy() {
FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean();
DelegatingFilterProxy proxy = new DelegatingFilterProxy();
proxy.setTargetFilterLifecycle(true);
proxy.setTargetBeanName("shiroFilter");
filterRegistrationBean.setFilter(proxy);
return filterRegistrationBean;
}
@Bean("shiroFilter")
public ShiroFilterFactoryBean shirFilter(SecurityManager securityManager){
ShiroFilterFactoryBean shiroFilterFactoryBean = new ShiroFilterFactoryBean();
// 必须设置 SecurityManager
shiroFilterFactoryBean.setSecurityManager(securityManager);
// setLoginUrl 如果不设置值,默认会自动寻找Web工程根目录下的"/login.jsp"页面 或 "/login" 映射
// shiroFilterFactoryBean.setLoginUrl("/login");
//设置成功跳转的页面
//shiroFilterFactoryBean.setSuccessUrl("/index");
// 设置无权限时跳转的 url;
//shiroFilterFactoryBean.setUnauthorizedUrl("/notRole");
// 设置拦截器
Map<String, String> filterChainDefinitionMap = new LinkedHashMap<>();
//游客,开发权限
//filterChainDefinitionMap.put("/**", "anon");
filterChainDefinitionMap.put("/guest/**", "anon");
//用户,需要角色权限 “user”
filterChainDefinitionMap.put("/user/**", "roles[user]");
//管理员,需要角色权限 “admin”
filterChainDefinitionMap.put("/admin/**", "roles[admin]");
//开放登陆接口
filterChainDefinitionMap.put("/api/ajaxLogin", "anon");
filterChainDefinitionMap.put("/login", "anon");
filterChainDefinitionMap.put("/loginUser", "anon");
//其余接口一律拦截
//主要这行代码必须放在所有权限设置的最后,不然会导致所有 url 都被拦截
filterChainDefinitionMap.put("/**", "authc");
//配置shiro默认登录界面地址,前后端分离中登录界面跳转应由前端路由控制,后台仅返回json数据
shiroFilterFactoryBean.setLoginUrl("/unauth");
shiroFilterFactoryBean.setFilterChainDefinitionMap(filterChainDefinitionMap);
System.out.println("Shiro拦截器工厂类注入成功");
return shiroFilterFactoryBean;
}
/*
注入securityManager
*/
@Bean
public SecurityManager securityManager(){
DefaultWebSecurityManager securityManager = new DefaultWebSecurityManager();
//设置REALM
securityManager.setRealm(customRealm());
return securityManager;
}
/*
自定义身份认证realm
必须写上这个类,并加上@Bean注解,目的是注入CustomRealm
否则会影响CustomRealm类中其他类的依赖注入
*/
@Bean
public MyShiroRealm customRealm(){
MyShiroRealm myShiroRealm = new MyShiroRealm();
myShiroRealm.setCredentialsMatcher(hashedCredentialsMatcher());// 将md5密码比对器传给realm
return myShiroRealm;
}
/*
开启注解支持
*/
@Bean
//@DependsOn({"lifecycleBeanPostProcessor"})
public DefaultAdvisorAutoProxyCreator advisorAutoProxyCreator(){
DefaultAdvisorAutoProxyCreator advisorAutoProxyCreator = new DefaultAdvisorAutoProxyCreator();
advisorAutoProxyCreator.setProxyTargetClass(true);
return advisorAutoProxyCreator;
}
@Bean
public AuthorizationAttributeSourceAdvisor authorizationAttributeSourceAdvisor(){
AuthorizationAttributeSourceAdvisor authorizationAttributeSourceAdvisor = new AuthorizationAttributeSourceAdvisor();
authorizationAttributeSourceAdvisor.setSecurityManager(securityManager());
return authorizationAttributeSourceAdvisor;
}
@Bean
public FilterRegistrationBean shiroSessionFilterRegistrationBean() {
FilterRegistrationBean filterRegistrationBean = new FilterRegistrationBean();
filterRegistrationBean.setFilter(new ShiroSessionFilter());
filterRegistrationBean.setOrder(FilterRegistrationBean.LOWEST_PRECEDENCE);
filterRegistrationBean.setEnabled(true);
filterRegistrationBean.addUrlPatterns("/*");
Map<String, String> initParameters = new HashMap<>();
initParameters.put("serverSessionTimeout", serverSessionTimeout);
initParameters.put("excludes", "/favicon.ico,/images/*,/js/*,/css/*,/static/*,/upload/*");
filterRegistrationBean.setInitParameters(initParameters);
return filterRegistrationBean;
}
/*@Bean
public ShiroDialect shiroDialect() {
return new ShiroDialect();
}*/
}
@Test
public void md5Test() {
String hashAlgorithName = "MD5";
String password = "123456";
int hashIterations = 1024;
ByteSource byteSource = ByteSource.Util.bytes("wujiesalt");
Object obj = new SimpleHash(hashAlgorithName, password, byteSource, hashIterations);
System.out.println("加密之后的密码" + obj);
}
@Controller
public class ShiroController {
@Resource
private LoginService loginService;
/**
* 登录方法
* @param userInfo
* @return
*/
@RequestMapping(value = "/api/ajaxLogin", method = RequestMethod.POST, produces = "application/json; charset=UTF-8")
@ResponseBody
public Result ajaxLogin(@RequestBody User userInfo) {
Subject subject = SecurityUtils.getSubject();
UsernamePasswordToken token = new UsernamePasswordToken(userInfo.getUsername(), userInfo.getPassword());
try {
subject.login(token);
LoginInfo loginInfo = loginService.getLoginInfo(userInfo.getUsername());
return ResultFactory.buildSuccessResult(loginInfo);// 将用户的角色和权限发送到前台
} catch (IncorrectCredentialsException e) {
return ResultFactory.buildFailResult("密码错误");
} catch (LockedAccountException e) {
return ResultFactory.buildFailResult("登录失败,该用户已被冻结");
} catch (AuthenticationException e) {
return ResultFactory.buildFailResult("该用户不存在");
} catch (Exception e) {
e.printStackTrace();
}
return ResultFactory.buildFailResult("登陆失败");
}
/**
* 未登录,shiro应重定向到登录界面,此处返回未登录状态信息由前端控制跳转页面
* @return
*/
@RequestMapping(value = "/unauth")
@ResponseBody
public Object unauth() {
Map<String, Object> map = new HashMap<String, Object>();
map.put("code", "1000000");
map.put("msg", "未登录");
return map;
}
}
@Service
public class LoginService {
@Resource
private SysRoleService sysRoleService;
@Resource
private UserRepository userRepository;
@Resource
private SysPermissionService sysPermissionService;
public LoginInfo getLoginInfo(String username) {
User user = userRepository.findByUsername(username).get();
List<SysRole> roles = sysRoleService.selectRoleByUserId(user.getId());
Set<String> roleList = new HashSet<>();
Set<String> permissionList = new HashSet<>();
for (SysRole role : roles) {
roleList.add(role.getRole());//角色存储
}
//此处如果多个角色都拥有某项权限,bu会数据重复,内部用的是Set
List<SysPermission> sysPermissions = sysPermissionService.selectPermByRole(roles);
for (SysPermission perm : sysPermissions) {
permissionList.add(perm.getPermission());//权限存储
}
return new LoginInfo(roleList,permissionList);
}
}
请输入代码/**
* Created by WJ on 2019/3/26 0026
*/
public class ResultFactory {
public static Result buildSuccessResult(LoginInfo data) {
return buidResult(ResultCode.SUCCESS, "成功", data);
}
public static Result buildFailResult(String message) {
return buidResult(ResultCode.FAIL, message, null);
}
public static Result buidResult(ResultCode resultCode, String message, LoginInfo data) {
return buidResult(resultCode.code, message, data);
}
public static Result buidResult(int resultCode, String message, LoginInfo data) {
return new Result(resultCode, message, data);
}
}
public class Result {
/**
* 响应状态码
*/
private int code;
/**
* 响应提示信息
*/
private String message;
/**
* 响应结果对象
*/
private LoginInfo loginInfo;
public Result(int code, String message, LoginInfo loginInfo) {
this.code = code;
this.message = message;
this.loginInfo = loginInfo;
}
public int getCode() {
return code;
}
public void setCode(int code) {
this.code = code;
}
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
public LoginInfo getLoginInfo() {
return loginInfo;
}
public void setLoginInfo(LoginInfo loginInfo) {
this.loginInfo = loginInfo;
}
}
<template>
<div class="login-wrap">
<div class="ms-login">
<div class="ms-title">土地经营管理系统</div>
<el-form :model="ruleForm" :rules="rules" ref="ruleForm" label-width="0px" class="ms-content">
<el-form-item prop="username">
<el-input v-model="ruleForm.username" placeholder="username">
<el-button slot="prepend" icon="el-icon-lx-people"></el-button>
</el-input>
</el-form-item>
<el-form-item prop="password">
<el-input
type="password"
placeholder="password"
v-model="ruleForm.password"
@keyup.enter.native="login"
>
<el-button slot="prepend" icon="el-icon-lx-lock"></el-button>
</el-input>
</el-form-item>
<div class="login-btn">
<el-button type="primary" @click="submitForm('ruleForm')">登录</el-button>
</div>
<p class="login-tips">Tips : 用户名和密码随便填。</p>
</el-form>
</div>
</div>
</template>
<script>
import {
setCookie,getCookie} from '../../assets/js/cookie';
export default {
data: function() {
return {
ruleForm: {
username: "",
password: ""
},
rules: {
username: [
{
required: true, message: "请输入用户名", trigger: "blur" }
],
password: [{
required: true, message: "请输入密码", trigger: "blur" }]
}
};
},
methods: {
submitForm(formName) {
this.$refs[formName].validate(valid => {
if (valid) {
this.$axios
.post("/api/ajaxLogin", {
// 请求后台登陆接口
username: this.ruleForm.username,
password: this.ruleForm.password
})
.then(successResponse => {
this.responseResult = JSON.stringify(successResponse.data);
if (successResponse.data.code === 200) {
console.log("登陆信息" + successResponse.data.loginInfo.roleList);
setCookie('roles',successResponse.data.loginInfo.roleList);// 使用cookie来记录是否登陆,这边跨域
let roles = getCookie('roles');
console.log('cookie' + roles);
localStorage.setItem("ms_username", this.ruleForm.username);// 使用localstoage来记录登陆信息
localStorage.setItem("roles", successResponse.data.loginInfo.roleList);
localStorage.setItem("permissions", successResponse.data.loginInfo.permissionList);
this.$router.push("/");// 跳转路由
}
if (successResponse.data.code === 400) {
let warnMessage = successResponse.data.message;
this.$message({
message: warnMessage,
type: 'warning'
})
}
});
} else {
console.log("error submit!!");
return false;
}
});
}
}
};
</script>
export function setCookie(key,value) {
var exdate = new Date();//获取时间
exdate.setTime(exdate.getTime() + 24 * 60 *60); //保存的天数,一天
//字符串拼接cookie
window.document.cookie = key + "=" + value + ";path=/;expires=" + exdate.toGMTString();
}
//读取cookie
export function getCookie(param) {
var c_param = '';
if (document.cookie.length > 0) {
console.log("原document cookie: " + document.cookie);
var arr = document.cookie.split('; '); //获取key value数组
for (var i = 0; i < arr.length; i++) {
var arr2 = arr[i].split('='); //获取该key 下面的 value数组
if(arr2[0] == param) {
c_param = arr2[1];
}
}
return c_param;
}
}
function padLeftZero (str) {
return ('00' + str).substr(str.length);
};
import axios from 'axios';
import ElementUI from 'element-ui';
import 'element-ui/lib/theme-chalk/index.css'; // 默认主题
// import '../static/css/theme-green/index.css'; // 浅绿色主题
import './assets/css/icon.css';
import './components/common/directives';
import "babel-polyfill";
import {
setCookie,getCookie} from './assets/js/cookie';
Vue.config.productionTip = false
Vue.use(ElementUI, {
size: 'small'
});
axios.default.baseURL = 'https://localhost:8888'
Vue.prototype.$axios = axios;
//使用钩子函数对路由进行权限跳转
router.beforeEach((to, from, next) => {
const roles = localStorage.getItem('roles');
const permissions = localStorage.getItem('permissions');
//这边可以用match()来判断所有需要权限的路径,to.matched.some(item => return item.meta.loginRequire)
let cookieroles = getCookie('roles');
console.log('cookie' + cookieroles);
if (!cookieroles && to.path !== '/login') {
// cookie中有登陆用户信息跳转页面,否则到登陆页面
next('/login');
} else if (to.meta.permission) {
// 如果该页面配置了权限属性(自定义permission)
// 如果是管理员权限则可进入
roles.indexOf('admin') > -1 ? next() : next('/403');
} else {
// 简单的判断IE10及以下不进入富文本编辑器,该组件不兼容
if (navigator.userAgent.indexOf('MSIE') > -1 && to.path === '/editor') {
Vue.prototype.$alert('vue-quill-editor组件不兼容IE10及以下浏览器,请使用更高版本的浏览器查看', '浏览器不兼容通知', {
confirmButtonText: '确定'
});
} else {
next();
}
}
})
// 在管理员页面配置 permission = true
import Vue from 'vue';
import Router from 'vue-router';
Vue.use(Router);
export default new Router({
routes: [
{
path: '/',
redirect: '/dashboard'
},
{
path: '/',
component: resolve => require(['../components/common/Home.vue'], resolve),
meta: {
title: '自述文件' },
children:[
{
path: '/dashboard',
component: resolve => require(['../components/page/Dashboard.vue'], resolve),
meta: {
title: '系统首页' }
},
{
path: '/icon',
component: resolve => require(['../components/page/Icon.vue'], resolve),
meta: {
title: '自定义图标' }
},
{
path: '/table',
component: resolve => require(['../components/page/BaseTable.vue'], resolve),
meta: {
title: '基础表格' }
},
{
path: '/tabs',
component: resolve => require(['../components/page/Tabs.vue'], resolve),
meta: {
title: 'tab选项卡' }
},
{
path: '/form',
component: resolve => require(['../components/page/BaseForm.vue'], resolve),
meta: {
title: '基本表单' }
},
{
// 富文本编辑器组件
path: '/editor',
component: resolve => require(['../components/page/VueEditor.vue'], resolve),
meta: {
title: '富文本编辑器' }
},
{
// markdown组件
path: '/markdown',
component: resolve => require(['../components/page/Markdown.vue'], resolve),
meta: {
title: 'markdown编辑器' }
},
{
// 图片上传组件
path: '/upload',
component: resolve => require(['../components/page/Upload.vue'], resolve),
meta: {
title: '文件上传' }
},
{
// vue-schart组件
path: '/charts',
component: resolve => require(['../components/page/BaseCharts.vue'], resolve),
meta: {
title: 'schart图表' }
},
{
// 拖拽列表组件
path: '/drag',
component: resolve => require(['../components/page/DragList.vue'], resolve),
meta: {
title: '拖拽列表' }
},
{
// 拖拽Dialog组件
path: '/dialog',
component: resolve => require(['../components/page/DragDialog.vue'], resolve),
meta: {
title: '拖拽弹框' }
},
{
// 权限页面
path: '/permission',
component: resolve => require(['../components/page/Permission.vue'], resolve),
meta: {
title: '权限测试', permission: true } // 配合钩子函数实现权限认证
},
{
path: '/404',
component: resolve => require(['../components/page/404.vue'], resolve),
meta: {
title: '404' }
},
{
path: '/403',
component: resolve => require(['../components/page/403.vue'], resolve),
meta: {
title: '403' }
}
]
},
{
path: '/login',
component: resolve => require(['../components/page/Login.vue'], resolve)
},
{
path: '*',
redirect: '/404'
}
]
})
Vue.directive('hasAuthorization',{
bind: (el) => {
const roles = localStorage.getItem('roles');
console.log(roles);
if(!(localStorage.getItem('roles').indexOf('admin') > -1)){
el.setAttribute('style','display:none')
}
}
})
//在按钮中设置指令,这样只有管理员才能看到这个按钮并使用,配置权限同理
<el-button type="text" icon="el-icon-edit" @click="handleEdit(scope.$index, scope.row)" v-hasAuthorization >编辑</el-button>
// 在vue.config.js中配置profxy
module.exports = {
baseUrl: './',
productionSourceMap: false,
devServer: {
proxy: {
'/api':{
target: 'http://127.0.0.1:8888',// 这里设置调用的域名和端口号,需要http,注意不是https!
changeOrigin: true,
pathRewrite: {
'^/api': '/api' //这边如果为空的话,那么发送到后端的请求是没有/api这个前缀的
}
}
}
}
}
//还要在man.js中配置axios
axios.default.baseURL = 'https://localhost:8888'
Vue.prototype.$axios = axios;
文章浏览阅读165次。加入水印,采用lsb%Name: Chris Shoemaker%Course: EER-280 - Digital Watermarking%Project: Least Significant Bit Substitution% Watermark Embedingclear all;% save start timestart_time=cputime;% read in the co..._[cover_object,map]=imread(file_name);
文章浏览阅读1.6w次。原文地址:http://www.xitongtiandi.net/wenzhang/win10/12654.htmlWin10专业版下ipv6无网络访问权限解决方案(只在win10专业版下做了测试,win7和win8.1待测试)1、首先打开 https://support.microsoft.com/en-us/kb/929852 选择Re-enable IPv6 相关的_ipv6无internet访问权限怎么办
文章浏览阅读3.1k次,点赞32次,收藏37次。而且每次都要直接使用上一步骤的具体运算结果(如2,6,24等),也不方便,应当能找到一种通用的表示方法。由于数值运算往往有现成的模型,可以运用数值分析方法,因此对数值运算的算法的研究比较深入,算法比较成熟。从图中可以看出:“其他”这一部分,包括不能被4整除的年份,以及能被4整除,又能被100整除,但不能被400整除的那些年份(如1900年),它们都是非闰年。:若year能被4整除,不能被100整除,则输出year的值和“是闰年”。因此,上述算法不仅是正确的,而且是计算机能方便实现的较好的算法。_程序等于数据结构+算法
文章浏览阅读2.6w次,点赞18次,收藏88次。记录一下碰到的问题解决方法第一步:首先最先要确定的是芯片和设置是否对应!!!!!!!!!第二步:确定芯片和设置对应无误后,再考虑下面的方法Keil : Error-Flash Download failed Cortex-M4错误解决方案整理在开发 nRF51822/nRF52832/nRF52840时候出现如下如下问题:问题: Keil电子下载时候出现 Error: Flash Download failed - "Cortex-M4"的错误,如下图根据官方教程解释如下,还是发现不容易解决,另_error: flash download failed - "cortex-m4
文章浏览阅读313次。在数据库编程中,很多朋友会碰到分割字符串的需求,一般都是分割成一列多行模式,但也有时会需要分割成多列一行的模式,下面我们来看下如何实现这种需求。首先创建一个辅助函数,来得到生成多列的SQL语句:create function toArray(@str nvarchar(1000),@sym nvarchar(10))returns nvarchar(3000)asbe..._sqlserver 字符串分割成多列 小提琴
文章浏览阅读1.3k次。配置MM32微控制器引脚复用功能文章目录配置MM32微控制器引脚复用功能IntroductionAlgorithmGPIOx_CR寄存器GPIOx_AFR寄存器GPIOx_CR & GPIOx_AFR寄存器TIMUARTSPI_MASTERSPI_SLAVEI2CCANADCFSMCQSPIDACCOMPSDIOUSBPraticeConclusionIntroduction使用过NXP(FSL)微控制器的开发者在配置引脚复用功能时,直接在PORT模块中,对应引脚的的PCR寄存器的MUX字段_mm32f单片机的bootloader串行口引脚
文章浏览阅读88次。 &n..._简明易懂 机器学习
文章浏览阅读134次。[color=darkred][size=x-large]存储过程学习总结[/size][/color][size=medium]1、存储过程基本语法:[/size]create procedure sp_name()begin ......end;[size=medium]2、如何调用:[/size]call sp_name();[size=medium]..._存储过程repeatuse near 'end repeat; close curgra;
文章浏览阅读97次。Neil Fraser文章看得糊里糊涂,e文不是很好...一般我们加载数据会生成一个script标签,在onload事件里remove掉,或者在jsonp回调函数中remove掉script标签,取得数据这样其实script占用的内存并没有释放,必须:for (var prop in jsFile) { delete jsFile[prop];}ie下不能d..._script加载的数据在哪里
文章浏览阅读77次。JavaScript 程序应该尽量放在 .js 的文件中,需要调用的时候在 HTML 中以 <script src="filename.js"> 的形式包含进来。JavaScript 代码若不是该 HTML 文件所专用的,则应尽量避免在 HTML 文件中直接编写 JavaScript 代码。因为这样会大大增加 HTML 文件的大小,无益于代码的压缩和缓存的使用。<scr..._js里的下载路径怎么做约束
文章浏览阅读604次。作者:池建强网址:macshuo.com微信:sagacity-mac问:池老师,我是个不爱互动的人,但是您所有的文章我都看了,非常感谢您的引导,我入手了人生第一台 MBP。现在问题来了,但是找不到更合适的人解答,只能求助于您了,如果您有时间的话。问题是这样的:我有个32bit unix file(开启一个服务进程),在 Mac 上执行时错误提示是:exec f_程序员价值
文章浏览阅读143次。测试工作总体流程图_测试的工作流程