什么是动态表单? 根据爱因斯坦相对论有动态表单说明是有静态表单的存在,生活中乃至世界任何两个有质量的物体都是运动的,这只是相对论的狭隘解析即狭义相对论,平常我们讨论的也往往是狭义相对论,这一理论的提出给物理学带来了革命性的变化,共同奠定了现
什么是动态表单?根据爱因斯坦相对论有动态表单说明是有静态表单的存在,生活中乃至世界任何两个有质量的物体都是运动的,这只是相对论的狭隘解析即狭义相对论,平常我们讨论的也往往是狭义相对论,这一理论的提出给物理学带来了革命性的变化,共同奠定了现代物理学的基础。相对论极大地改变了人类对宇宙和自然的“常识性”观念,丰富了我们的常识。
看到动态表单也许你会想到动态、静态网页,它们和动态表单有什么区别呢?我觉的它们本质没有区别只是生成的时间不同而已,静态网页在编码阶段即可固定,以后它的内容也不会再有所改变;动态网页虽然编码阶段结构也确定了但是它的内容可以改变,可以让用户自己选择、可以和用户交互。
动态表单的目的是为了根据业务流程不同灵活设计显示页面,显然,在业务流程设计阶段不用过多的考虑表单如何实现,将业务流程与表单显示分离开了,充分体现了MVC思想,我们可以把动态表单看成了V层的具体实现。
动态表单建模记得前几天看了一本小书叫《成交》,深刻剖析了一个大型IT公司的发展历程以及各个人物的思想活动里面有一句“攻城为下,攻心为上”,这句话说的的确很对,在生成表单时只有知道表单核心组成元素才能组装出表单,生成动态表单时也展现出了另一个编程思想OOP面向对象编程,生成表单也就是组装过程,按照这个思想我们把表单拆分、建模,持久化到数据库中。
下图是抽象出来的表单类图
一个表单是由多个表单域组成,每个表单域有名称、输入框类型、输入数据类型,如果是列表框还会有条目的添加,这就是最简单的动态表单,如果表单上还有一些复杂控件会麻烦一些但是流程是一样的。
持久化到数据库中
将表单数据保存到数据库中,等需要的时候直接从数据库里面加载即可,看一下生成的一些表。
表单的显示
下一篇博客中将介绍表单显示,通过freemarker插件来动态显示页面!

Installing MySQL on Linux can be done through the package manager. The specific steps are as follows: 1. On Ubuntu, use apt to update the package list and install the MySQL server; 2. On CentOS, use yum to install the MySQL community version and start the service. After installation, basic configuration needs to be performed, such as setting the root password and creating database and users.

MySQL views are virtual tables generated based on SQL queries. 1. Create a view: Use the CREATEVIEW statement combined with SELECT query. 2. Usage scenarios: simplify complex queries, data abstraction and ensure data consistency. 3. Optimization strategy: simplify underlying queries, use indexes, and consider materialized views.

When creating a database in MySQL, character sets and collation rules should be specified to ensure data accuracy and improve query performance. 1) Use the CREATEDATABASEmy_databaseCHARACTERSETutf8mb4COLLATIONutf8mb4_unicode_ci command to create a database, select the utf8mb4 character set and utf8mb4_unicode_ci collation. 2) utf8mb4 supports more Unicode characters, while utf8mb4_unicode_ci provides case-insensitive comparisons. 3) Ensure that the application layer and database layer use the same character set and collation rules to avoid potential problems.

In MySQL, sorting uses the ORDERBY clause, and ranking uses the RANK(), DENSE_RANK(), and ROW_NUMBER() functions. 1. Sort: Use ORDERBY clause, such as SELECT*FROMemployeesORDERBYsalaryDESC; 2. Ranking: Use window functions, such as SELECTemployee_name, salary, RANK()OVER(ORDERBYsalaryDESC)ASrankFROMemployees; these operations are based on SQL query optimizer and execution engine, and are often used to sort quickly or merge sort, and ranking depends on window function calculation.

To create and call stored procedures in MySQL, follow the following steps: 1. Create stored procedures: Use the CREATEPROCEDURE statement to define stored procedures, including names, parameters, and SQL statements. 2. Compile stored procedures: MySQL compiles stored procedures into executable code and stores them. 3. Call stored procedure: use CALL statement and pass parameters. 4. Execute stored procedures: MySQL executes the SQL statements in it, processes parameters and returns the result.

The MySQL service can be set to automatically start on Windows, Linux, and macOS. 1) On Windows, use the command "scconfigmysqlstart=auto" to configure. 2) On Linux, enable it using "sudosystemctlenablemysql". 3) On macOS, create and load the launchd configuration file to achieve automatic startup.

The methods to view the MySQL table structure include: 1. Use the DESCRIBE command to view column information; 2. Use the SHOWCREATETABLE command to view table creation statements; 3. Use information_schema to query more detailed information. These methods help to quickly understand table structure and improve work efficiency.

Installing MySQL on macOS can be achieved through the following steps: 1. Install Homebrew, using the command /bin/bash-c"$(curl-fsSLhttps://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)". 2. Update Homebrew and use brewupdate. 3. Install MySQL and use brewinstallmysql. 4. Start MySQL service and use brewservicesstartmysql. After installation, you can use mysql-u


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