.net core试水

概述

大概记录下我如何第一次使用.net core搭建一个api，由于最近.net core比较火，我也尝试着使用.net core做了一个小功能

本文主要包括

1.环境配置

2.程序编写

3.程序部署

主要参考：https://docs.microsoft.com/zh-cn/aspnet/core/tutorials/first-web-api?view=aspnetcore-3.1&tabs=visual-studio

1、环境配置

想要使用.net core3.1 第一个问题是更新VS，更新过程中遇到报错

VS_InstallerShell.exe has an invalid certificate. Please ensure the appropriate Microsoft certificates are installed

网上很多方法试过没有效果，最后在哪里（自己也忘记了）找到了解决方案，安装两个windows补丁，附上补丁编号和下载地址

https://www.catalog.update.microsoft.com/Home.aspx

KB4474419
kb4490628

2.程序编写

安装了最新vs以后，点击新建项目，创建3.1 .net core API项目，创建以后可以直接运行，会有一个天气预报的示例

使用Nuget安装Microsoft.EntityFrameworkCore.SqlServr，ef我虽然没有在实际项目中使用过，不过陆陆续续知道点，今天顺便试试

2.1 创建数据库上下文类

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.Data.SqlClient;
using Microsoft.EntityFrameworkCore;

namespace reportAPI
{
    public class ChartDesignContenxt: DbContext
    {
        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        {
            var sqlConnectionStringBuilder = new SqlConnectionStringBuilder
            {
                DataSource = "*.*.*.*",
                InitialCatalog = "*",
                UserID = "sa",
                Password = "123456"
            };
            optionsBuilder.UseSqlServer(sqlConnectionStringBuilder.ConnectionString);

            base.OnConfiguring(optionsBuilder);
        }
        public DbSet<chartDesign> chartDesigns { get; set; }
    }
}

2.2 在startup.cs类中注入数据库上下文类，添加跨域配置

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.HttpsPolicy;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Microsoft.Extensions.Logging;

namespace reportAPI
{
    public class Startup
    {
        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public IConfiguration Configuration { get; }

        // This method gets called by the runtime. Use this method to add services to the container.
        public void ConfigureServices(IServiceCollection services)
        {
            //允许一个或多个具体来源:
            services.AddCors(options =>
            {
                // 配置跨域
                options.AddPolicy("cors", policy =>
                {
                    // 设定允许跨域的来源，有多个的话可以用 `,` 隔开
                    policy
                            .AllowAnyOrigin()
                            .AllowAnyHeader()
                            .AllowAnyMethod();
                });
            });

            services.AddScoped<IPMSDbContenxt>(_ => new IPMSDbContenxt());   
            services.AddScoped<ChartDesignContenxt>(_ => new ChartDesignContenxt());   //注入数据库上下文类

            services.AddControllers();
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }

            app.UseHttpsRedirection();

            app.UseRouting();
    
            app.UseCors("cors");  //使用跨域

            app.UseAuthorization();

            app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllers();
            });
        }
    }
}

2.3 创建控制器，一共三个方法，获取列表，更新一条记录，获取一条记录

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;

namespace reportAPI.Controllers
{
    [Route("api/[controller]/[action]")]
    [ApiController]
    public class ChartDesignController : ControllerBase
    {
        private readonly ChartDesignContenxt _context;

        public ChartDesignController(ChartDesignContenxt context)
        {
            _context = context;
        }

        [HttpPost]
        public IActionResult Save(CommonFilter filter)
        {
            try
            {
                //var temp = entity.data.ToString();
                chartDesign model = new chartDesign();
                model.designName = filter.field1;
                model.designContent = filter.data.ToString();
                if (filter.key == -1)
                {
                    _context.Add<chartDesign>(model);
                }
                else
                {
                    model.designId = filter.key;
                    _context.Update<chartDesign>(model);
                }
                _context.SaveChanges();
                return Ok("保存成功");
            }
            catch(Exception ex)
            {
                return Ok(ex.Message);
            }
           
        }
        [HttpPost]
        public IActionResult Get(CommonFilter filter)
        {
            try
            {
                chartDesign entity = _context.chartDesigns.Find(filter.key);
                if (entity == null)
                {
                    return NotFound();
                }

                return Ok(entity);
            }
            catch(Exception ex)
            {
                return Ok(ex.Message);
            }
        }
        [HttpPost]
        public IActionResult GetList()
        {
            try
            {
                string sql = "select * from chartDesign";
                List<chartDesign> list = _context.chartDesigns.ToList(); //.FromSqlRaw(sql).ToList();
                return Ok(list);
            }
            catch (Exception ex)
            {
                return Ok(ex.Message);
            }
        }
    }
}

一个增删改完成

3.部署到服务器

部署比较简单，直接拷贝bin下面的内容，然后双击  项目名.exe 服务就启动起来了