各种ORM框架对比（理论篇，欢迎来观摩，并且纠正部分错误，防止误区）

//保存对象

db.Save(article);

db.Save(new Article { Title = "Super easy to use PetaPoco" });

db.Save("Articles", "Id", { Title = "Super easy to use PetaPoco", Id = Guid.New() });

//获取一个对象

var article = db.Single<Article>();

var article = db.Single<Article>("WHERE ArticleKey = @0", "ART-123");

//删除一个对象

db.Delete(article);

db.Delete<Article>();

db.Delete("Articles", "Id", );

db.Delete("Articles", "ArticleKey", "ART-123");

//IDbConnection扩展查询

public  static  IEnumerable < T > Query < T >（this IDbConnection conn，string  sql，object  param  =  null，SqlTransaction  transaction  =  null，bool  buffered  =  true）

public class Dog

{

    public int? Age { get; set; }

    public Guid Id { get; set; }

    public string Name { get; set; }

    public float? Weight { get; set; }

    public int IgnoredProperty { get { return ; } }

}

//简单查询

var guid = Guid.NewGuid();

var dog = connection.Query<Dog>("select Age = @Age, Id = @Id", new { Age = (int?)null, Id = guid });

//验证统计数量

dog.Count()

    .IsEqualTo();

//验证属性是否为null

dog.First().Age

    .IsNull();

//验证属性是否匹配

dog.First().Id

    .IsEqualTo(guid);

//查询两行数据
var rows = connection.Query("select 1 A, 2 B union all select 3, 4");

//行一数据

((int)rows[].A)

   .IsEqualTo();

((int)rows[].B)

   .IsEqualTo();

//行二数据

((int)rows[].A)

   .IsEqualTo();

((int)rows[].B)

    .IsEqualTo();

public static int Execute(this IDbConnection cnn, string sql, object param = null, SqlTransaction transaction = null)

connection.Execute(@"

  set nocount on

  create table #t(i int)

  set nocount off

  insert #t

  select @a a union all select @b

  set nocount on

  drop table #t", new {a=, b= })

   .IsEqualTo();

connection.Execute(@"insert MyTable(colA, colB) values (@a, @b)",

    new[] { new { a=, b= }, new { a=, b= }, new { a=, b= } }

  ).IsEqualTo();

public class Products:DynamicModel {

    public Products():base("northwind", "products","productid") {}

}

var table = new Products();

var products = table.All();

//获取查询字段和搜索条件

var productsFour = table.All(columns: "ProductName as Name", where: "WHERE categoryID=@0",args: );

//分页查询

var result = tbl.Paged(where: "UnitPrice > 20", currentPage:, pageSize: );

var poopy = new {ProductName = "Chicken Fingers"};

//更新 Product对象到表， 条件 ProductID = 12 ，设置 ProductName of "Chicken Fingers"

table.Update(poopy, )

//插入数据

var table = new Categories();

var inserted = table.Insert(new {CategoryName = "Buck Fify Stuff", Description = "Things I like"});

//插入成功后得到返回新对象

var newID = inserted.CategoryID;

//插入数据

public int Insert(Employee employee)

{

    return m_DataSource.Insert("HR.Employee", employee).ToInt32().Execute();

}

//更新数据

public void Update(Employee employee)

{

    m_DataSource.Update("HR.Employee", employee).Execute();

}

//初学者更新实体（但容易出问题，如果对应的漏写了一个属性的赋值）

public void Update(Employee employee)

{

    using (var context = new CodeFirstModels())

    {

        var entity = context.Employees.Where(e => e.EmployeeKey == employee.EmployeeKey).First();

        entity.CellPhone = employee.CellPhone;

        entity.FirstName = employee.FirstName;

        entity.LastName = employee.LastName;

        entity.ManagerKey = employee.ManagerKey;

        entity.MiddleName = employee.MiddleName;

        entity.OfficePhone = employee.OfficePhone;

        entity.Title = employee.Title;

        context.SaveChanges();

    }

}

//中级者更新

public void Update(Employee employee)

{

    using (var context = new CodeFirstModels())

    {

        context.Entry(employee).State = EntityState.Modified;

        context.SaveChanges();

    }

}

//获取指定表全部数据

public IList<Employee> GetAll()

{

    return m_DataSource.From("HR.Employee").ToCollection<Employee>().Execute();

}

Console.WriteLine($"开始Chloe测试");
using (MsSqlContext msSqlContext = new MsSqlContext("server=(local);user id=test;password=test;database=TestDb;"))
{
IQuery<Order> query = msSqlContext.Query<Order>();
//预热，因为我没去查阅你的源码，默认考虑预热
query.FirstOrDefault();
Stopwatch stopwatch = Stopwatch.StartNew();
IList<long> tmsList = new List<long>();
for (int i = 0; i < 10; i++)
{
stopwatch.Restart();
var data = query.ToList();
stopwatch.Stop();
var tms = stopwatch.ElapsedMilliseconds;
tmsList.Add(tms);
Console.WriteLine($"耗时：{tms}");
}
Console.WriteLine($"平均：{tmsList.Average()}");
Console.ReadKey();
}

Console.WriteLine($"开始Dapper测试");
using (IDbConnection connection = new SqlConnection("server=(local);user id=test;password=test;database=TestDb;"))
{
//也进行预热
connection.QueryFirst("SELECT TOP 1 OrderId,OrderNo FROM [Order]");
Stopwatch stopwatch = Stopwatch.StartNew();
IList<long> tmsList = new List<long>();
for (int i = 0; i < 10; i++)
{
stopwatch.Restart();
var data = connection.Query<Order>("SELECT OrderId,OrderNo FROM [Order]"); ;
stopwatch.Stop();
var tms = stopwatch.ElapsedMilliseconds;
tmsList.Add(tms);
Console.WriteLine($"耗时：{tms}");
}
Console.WriteLine($"平均：{tmsList.Average()}");
Console.ReadKey();
}