class Program
{
static void Main(string[] args)
{
TestContext testContext = new TestContext();
///获取数据库表Person中的所有数据 在查询的时候最好加上AsNoTracking 禁止EF跟踪
// var personList = testContext.Persons.AsNoTracking().ToList();
}
}
public class TestContext : DbContext
{
private static TestContext _instance;
public static TestContext Instance
{
get
{
if (_instance == null)
{
_instance = new TestContext();
}
return _instance;
}
}
private string _connectionString;
public string ConnectionString
{
get
{
if (string.IsNullOrWhiteSpace(_connectionString))
{
_connectionString = ConfigurationManager.ConnectionStrings["testConn"].ConnectionString;
}
return _connectionString;
}
set
{
_connectionString = value;
}
}
public TestContext()
: base("name=testConn")
{
_connectionString = ConfigurationManager.ConnectionStrings["testConn"].ConnectionString;
}
public TestContext(string connectionString)
: base(connectionString)
{
}
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
///DomainMapping 所在的程序集一定要写对,因为目前在当前项目所以是采用的当前正在运行的程序集 如果你的mapping在单独的项目中 记得要加载对应的assembly
///这是重点
var typesToRegister = Assembly.GetExecutingAssembly().GetTypes()
.Where(type => !String.IsNullOrEmpty(type.Namespace))
.Where(type => type.BaseType != null && type.BaseType.BaseType != null && type.BaseType.BaseType.GetGenericTypeDefinition() == typeof(EntityTypeConfiguration<>));
foreach (var type in typesToRegister)
{
dynamic configurationInstance = Activator.CreateInstance(type);
modelBuilder.Configurations.Add(configurationInstance);
}
base.OnModelCreating(modelBuilder);
}
}
public class BaseDomain
{
}
[Table("Person")]
public class Person
{
public string ID { get; set; }
public string Name { get; set; }
public string Age { get; set; }
}
public class PersonMapping : BaseDomainMapping<Person>
{
public override void Init()
{
this.ToTable("Person");
this.HasKey(l => l.ID);
this.Property(l => l.Name).HasMaxLength(200).IsRequired();//设置Name属性长度为200 并且是必填
this.Property(l => l.Age).HasMaxLength(200).IsOptional(); //设置Age长度为200 并且可为空
}
}
public abstract class BaseDomainMapping<T> : EntityTypeConfiguration<T>
where T : BaseDomain, new()
{
public BaseDomainMapping()
{
Init();
}
/// <summary>
/// 初始化代码
/// </summary>
public virtual void Init()
{
Console.WriteLine("Init");
}
}
http://www.cnblogs.com/jiagoushi/p/4051270.html