Asp.Net Core 轻松学-使用MariaDB/MySql/PostgreSQL和支持多个上下文对象 (3)

日期：2021-05-09 栏目：程序人生浏览：次

在 Ron.OtherDB 项目中，我们一共创建了两个 Context ，分别是 MySqlForumContext 和 NPgSqlForumContext，这两个 Context 可以在项目中一起使用，互不影响

3.1 在 HomeController 注入两个 Context private MySqlForumContext mysqlContext; private NPgSqlForumContext pgsqlContext; public HomeController(MySqlForumContext mysqlContext, NPgSqlForumContext pgsqlContext) { this.mysqlContext = mysqlContext; this.pgsqlContext = pgsqlContext; } `` > 注入的方式非常简单，和其它类型的注入使用方式没有区别，就是简单的在 HomeController 的构造函数中声明这两个 Context 对象即可 #####3.2 使用两个上下文对象进行 CURD 操作 > 下面将演示使用 MySqlForumContext 和 NPgSqlForumContext 进行简单的 CURD 操作，这个操作过程和上一篇的 MSSQL 几乎是完全相同的，代码比较简单，就直接贴上来了 [Route("api/[controller]"), ApiController] public class HomeController : ControllerBase { private MySqlForumContext mysqlContext; private NPgSqlForumContext pgsqlContext; public HomeController(MySqlForumContext mysqlContext, NPgSqlForumContext pgsqlContext) { this.mysqlContext = mysqlContext; this.pgsqlContext = pgsqlContext; } [HttpGet] public ActionResult Get() { // MySql var mysqlTopics = this.mysqlContext.Topics.ToList(); // PgSql var pgsqlTopics = this.pgsqlContext.Topics.ToList(); return new JsonResult(new { mysql = mysqlTopics, pgsql = pgsqlTopics }); } [HttpPost] public async Task Post([FromBody] TopicViewModel model) { // MySql this.mysqlContext.Topics.Add(new Topic() { Content = model.Content, CreateTime = DateTime.Now, Title = model.Title }); await this.mysqlContext.SaveChangesAsync(); // PgSql this.pgsqlContext.Topics.Add(new Topic() { Content = model.Content, CreateTime = DateTime.Now, Title = model.Title }); await this.pgsqlContext.SaveChangesAsync(); } [HttpPut] public async Task Put([FromBody] TopicViewModel model) { // MySql var topic = this.mysqlContext.Topics.Where(f => f.Id == model.Id).FirstOrDefault(); topic.Title = model.Title; topic.Content = model.Content; await this.mysqlContext.SaveChangesAsync(); // PgSql var pgTopic = this.pgsqlContext.Topics.Where(f => f.Id == model.Id).FirstOrDefault(); pgTopic.Title = model.Title; pgTopic.Content = model.Content; await this.pgsqlContext.SaveChangesAsync(); } [HttpDelete("{id}")] public async Task Delete(int id) { // MySql var topic = this.mysqlContext.Topics.Where(f => f.Id == id).FirstOrDefault(); this.mysqlContext.Topics.Remove(topic); await this.mysqlContext.SaveChangesAsync(); // PgSql var pgTopic = this.pgsqlContext.Topics.Where(f => f.Id == id).FirstOrDefault(); this.pgsqlContext.Topics.Remove(pgTopic); await this.pgsqlContext.SaveChangesAsync(); } }

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3.3 打开控制台执行 dotnet run

Asp.Net Core 轻松学-使用MariaDB/MySql/PostgreSQL和支持多个上下文对象