.NET Core 2.1 EF(Entity Framework) Core Sqlite配置和使用分享

1、安装用到的Nuget包

项目上右键 -》选择"管理Nuget程序包" -》搜索"Microsoft.EntityFrameworkCore.Sqlite" -》点击"Microsoft.EntityFrameworkCore.Sqlite"安装,还要安装"Microsoft.EntityFrameworkCore.Sqlite.Core"和"Microsoft.EntityFrameworkCore.Tools"。

Nuget使用教程

2、连接字符串和数据库中字段验证

using Microsoft.EntityFrameworkCore;
using SpiderContent.Data.Models;
using System;
using System.Collections.Generic;
using System.Text;
namespace SpiderContent.Data
{
    public class SpiderContext : DbContext
    {
        public DbSet PageInfos { get; set; }

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        {
            optionsBuilder.UseSqlite("Filename=./spider.db");
        }
        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            base.OnModelCreating(modelBuilder);
            modelBuilder.Entity(entity =>
            {
                entity.HasKey(e => e.Id);
                entity.Property(e => e.Title).IsRequired();
            });
        }
    }
}

3、数据库初始化和工具方法代码

using Microsoft.Extensions.Configuration;using SpiderContent.Data.Models;using System;using System.Linq;using System.Reflection;namespace SpiderContent.Data{    public class Utils    {        /// 
        /// 用来初始化数据库，没有则新建数据库        /// 
        static Utils()        {            using (var context = new SpiderContext())            {                context.Database.EnsureCreated();            }        }         /// 
        /// 获取配置信息        /// 
             private static IConfigurationRoot configuration;        public static IConfigurationRoot Configuration        {            get            {                if (configuration == null)                {                    var builder = new ConfigurationBuilder().AddJsonFile("appsettings.json");                    configuration = builder.Build();                }                return configuration;            }        }        public static void SaveData(PageInfo pageInfo)        {            using (var context = new SpiderContext())            {                context.PageInfos.Add(pageInfo);                context.SaveChanges();            }        }        public static void SaveOrUpdate(PageInfo pageInfo)        {            using (var context = new SpiderContext())            {                PageInfo p = context.PageInfos.Where(w => w.Url.Trim() == pageInfo.Url.Trim()).FirstOrDefault();                if (p != null)                {                    p.Page = pageInfo.Page;                    p.PlainText = pageInfo.PlainText;                    p.Title = pageInfo.Title;                    p.Url = pageInfo.Url;                    p.views = pageInfo.views;                    p.votes = pageInfo.votes;                    p.answers = pageInfo.answers;                    p.askedTime = pageInfo.askedTime;                    p.askedTimeBounty = pageInfo.askedTimeBounty;                    p.description = pageInfo.description;                    context.Update(p);                }                else                {                    context.Add(pageInfo);                }                context.SaveChanges();            }        }        public static PageInfo ToPageInfo(object model)        {            PageInfo pageInfo = new PageInfo();            PropertyInfo property = null;            foreach (var item in typeof(PageInfo).GetProperties())            {                property = model.GetType().GetProperty(item.Name);                if (property != null)                {                    item.SetValue(pageInfo, property.GetValue(model));                }            }            return pageInfo;        }    }}