![.Net 常用ORM框架对比：EF Core、FreeSql、SqlSuger
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1 /// Students { get; set; }
13 [SugarColumn(IsIgnore = true)]
14 public virtual ICollection Classs { get; set; }//
15 }
16 /// ClassStudents { get; set; }//班级学生
29 [SugarColumn(IsIgnore = true)]
30 public virtual ICollection Students { get; set; }//选修学生
31 }
32 /// Courses { get; set; }//辅修课、自选课
49 }
50 {
51 /// public class EfDbContext : DbContext
{
/// options)
: base(options)
{
}
private string Conn = null;
public DbContext ToWriteOrRead(string conn)
{
Conn = conn;
return this;
}
protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
{
if (!optionsBuilder.IsConfigured)
{
optionsBuilder.UseLoggerFactory(MyLoggerFactory)
//.UseLazyLoadingProxies()
.UseSqlServer(Conn);
}
optionsBuilder.UseLoggerFactory(MyLoggerFactory);
}
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
#region MyRegion
{
//指定主键
//modelBuilder.Entity().HasKey(a => a.Id);
/////设置数据库架构
//modelBuilder.HasDefaultSchema("xl");
/////表名、属性名映射
//modelBuilder.Entity().ToTable("UserInfos", "Zhaoxi").Property(p => p.UserAge).HasColumnName("Age");
////设置联合主键
//modelBuilder.Entity().HasKey(p => new { p.SysUserId, p.SysRoleId });
////初始化数据
//modelBuilder.Entity().HasData(new List()
//{
//});
///////表拆分:在数据库中是一整张表，在代码层面是多个实体与其对应；
//modelBuilder.Entity(dob =>
//{
// dob.ToTable("SysLogInfo");
// dob.Property(o => o.LogType).HasColumnName("LogType");//配置两个实体的相同属性映射到表的同一列
// dob.HasOne(o => o.SysLogDetail).WithOne().HasForeignKey(o => o.Id); ; //配置两个实体的相同属性映射到表的同一列
//});
//modelBuilder.Entity(dob =>
//{
// dob.ToTable("SysLogInfo");
// dob.Property(o => o.LogType).HasColumnName("LogType");//配置两个实体的相同属性映射到表的同一列
//});
}
//设置一对多的关系
modelBuilder.Entity().HasOne(c => c.Class).WithMany(s => s.Students).HasForeignKey(b => b.ClassId);
////多对多关系
modelBuilder.Entity(eb =>
{
eb.HasOne(p => p.Course).WithMany(u => u.Students).HasForeignKey(u => u.CourseId);
eb.HasOne(p => p.Student).WithMany(r => r.Courses).HasForeignKey(s => s.StudentId);
});
modelBuilder.Entity(eb => {
eb.HasOne(p => p.Course).WithMany(u => u.ClassStudents).HasForeignKey(u => u.CourseId);
eb.HasOne(p => p.Class).WithMany(r => r.Classs).HasForeignKey(s => s.ClassId);
});
#endregion
}
public DbSet Classs { get; set; }
public DbSet Students { get; set; }
public DbSet Courses { get; set; }
} public class FreeSqlContext: DbContext
{
public DbSet Students { get; set; }
public DbSet Courses { get; set; }
public DbSet ClassGrades { get; set; }
public DbSet MiddleClassCourses { get; set; }
public DbSet MiddleStudentCourses { get; set; }
//每个 DbContext 只触发一次
protected override void OnModelCreating(ICodeFirst codefirst)
{
codefirst.Entity(eb =>
{
eb.HasOne(a => a.Class).HasForeignKey(b => b.ClassId).WithMany(c => c.Students);
});
codefirst.Entity(eb =>
{
eb.HasOne(a => a.Student).WithMany(t => t.Courses).HasForeignKey(b => b.StudentId);
eb.HasOne(a => a.Course).WithMany(t => t.Students).HasForeignKey(a => a.CourseId);
});
codefirst.Entity(eb =>
{
eb.HasOne(a => a.Course).WithMany(t => t.ClassStudents).HasForeignKey(a => a.CourseId);
eb.HasOne(a => a.Class).WithMany(t => t.Students).HasForeignKey(a => a.ClassId);
});
}
} public class SqlSugerContext: SimpleClient where T : class, new()
{
public SqlSugerContext(SqlSugarClient context) : base(context)//注意这里要有默认值等于null
{
context.CodeFirst.SetStringDefaultLength(200).InitTables(typeof(T));//这样一个表就能成功创建了
}
}
public class ClassGradeService: SqlSugerContext
{
public ClassGradeService(SqlSugarClient context):base(context)
{
}
}
public class CourseService: SqlSugerContext
{
public CourseService(SqlSugarClient context) : base(context)
{
}
}
public class StudentService: SqlSugerContext
{
public StudentService(SqlSugarClient context) : base(context)
{
}
}
public class MiddleClassCourseCervice : SqlSugerContext
{
public MiddleClassCourseCervice(SqlSugarClient context) : base(context)
{
}
}
public class MiddleStudentCourseService : SqlSugerContext
{
public MiddleStudentCourseService(SqlSugarClient context) : base(context)
{
}
} "EfConnectionStrings": {
"WriteConnection": "Server=localhost;Database=DbEfCore;Trusted_Connection=True;",
"ReadConnectionList": [
"Server=localhost;Database=DbEfCore;Trusted_Connection=True;"
]
},
"FreeSqlConnectionStrings": "Server=localhost;Database=DbFreeSql;Trusted_Connection=True;",
"SqlSugerConnectionStrings": "Server=localhost;Database=DbSqlSuger;Trusted_Connection=True;" public enum WriteAndReadEnum
{
Write, //主库操作
Read //从库操作
}
public interface IDbContextFactory
{
public EfDbContext ConnWriteOrRead(WriteAndReadEnum writeAndRead);
}
public class DBConnectionOption
{
public string WriteConnection { get; set; }
public List ReadConnectionList { get; set; }
}
public class DbContextFactory : IDbContextFactory
{
private readonly EfDbContext _Context = new EfDbContext();
private static int _iSeed = 0;
private readonly DBConnectionOption _readAndWrite = null;
public DbContextFactory(IOptionsMonitor options)
{
_readAndWrite = options.CurrentValue;
}
public EfDbContext ConnWriteOrRead(WriteAndReadEnum writeAndRead)
{
//判断枚举，不同的枚举可以创建不同的Context 或者更换Context链接；
switch (writeAndRead)
{
case WriteAndReadEnum.Write:
ToWrite();
break; //选择链接//更换_Context链接 //选择链接
case WriteAndReadEnum.Read:
ToRead();
break; //选择链接//更换_Context链接
default:
break;
}
return _Context;
}
///
/// 更换成主库连接
///
///
/// 更换成主库连接
///
/// ///策略---数据库查询的负载均衡
///
/// #region FreeSql//DbFreeSql
var freestr = Configuration.GetSection("FreeSqlConnectionStrings").Value;
IFreeSql fsql = new FreeSql.FreeSqlBuilder()
.UseConnectionString(FreeSql.DataType.SqlServer, freestr)
.UseSlave(freestr)//使用从数据库，支持多个
.UseAutoSyncStructure(true) //自动同步实体结构到数据库
.Build(); //请务必定义成 Singleton 单例模式
services.AddSingleton(fsql);
services.AddFreeDbContext(options => options.UseFreeSql(fsql));
#endregion
#region SqlSuger//DbSqlSuger
var sugerstr = Configuration.GetSection("SqlSugerConnectionStrings").Value;
services.AddScoped(options => new SqlSugarClient(new ConnectionConfig()
{
ConnectionString = sugerstr,//连接符字串
DbType = DbType.SqlServer,
IsAutoCloseConnection = true,
InitKeyType = InitKeyType.Attribute,//从特性读取主键自增信息
SlaveConnectionConfigs = new List() {//使用从数据库，支持多个
new SlaveConnectionConfig() { HitRate=10, ConnectionString=sugerstr }
}
}));
services.AddScoped();
services.AddScoped();
services.AddScoped();
services.AddScoped();
services.AddScoped();
#endregion
#region EfCore//DbEfCore
services.AddDbContext(options => options.UseSqlServer("name=EfConnectionStrings:WriteConnection"));
services.Configure(Configuration.GetSection("EfConnectionStrings"));//注入多个链接
services.AddTransient();
#endregion .Net 常用ORM框架对比：EF Core、FreeSql、SqlSuger
原文地址：https://www.cnblogs.com/xl-tf/p/14163360.html
