我想了解如何在StructureMap中使用策略example 2。我创建了一个小测试项目(下面的代码)。遗憾的是,由于某些原因,似乎存在一些依赖性问题,因为.As<type>
和.Each
都不起作用。
对于使用As
的行,例如
user.Green.As<Database>().ConnectionString.ShouldBe("*green*");
我收到错误:
'IDatabase'不包含'As'的定义,也没有扩展方法'As'可以找到接受'IDatabase'类型的第一个参数(你是否缺少using指令或汇编引用?)。对于这一行:
instance.Constructor.GetParameters()
.Where(x => x.ParameterType == typeof(IDatabase))
.Each(param => ...
'StringExtensions.Each(IEnumberable,Action)'由于其保护级别而无法访问。
我使用NuGet安装了StructureMap 4.2。正如您在下面的代码中看到的,我输入了StructureMap中的所有using
- 语句,我可以找到,但我仍然遇到问题。
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using StructureMap;
using StructureMap.Pipeline;
using StructureMap.Pipeline.Lazy;
using StructureMap.Configuration;
using StructureMap.Building;
using StructureMap.Attributes;
using StructureMap.AutoMocking;
using StructureMap.Graph;
using StructureMap.Query;
using StructureMap.TypeRules;
using StructureMap.Util;
using StructureMap.Building.Interception;
using StructureMap.Configuration.DSL;
using StructureMap.Diagnostics.TreeView;
using StructureMap.Graph.Scanning;
namespace TestStructureMapPolicies
{
class Program
{
static void Main(string[] args)
{
var container = new Container(_ =>
{
_.For<IDatabase>().Add<Database>().Named("red")
.Ctor<string>("connectionString").Is("*red*");
_.For<IDatabase>().Add<Database>().Named("green")
.Ctor<string>("connectionString").Is("*green*");
_.Policies.Add<InjectDatabaseByName>();
});
// ImportantService should get the "red" database
container.GetInstance<ImportantService>()
.DB.As<Database>().ConnectionString.ShouldBe("*red*");
// BigService should get the "green" database
container.GetInstance<BigService>()
.DB.As<Database>().ConnectionString.ShouldBe("*green*");
// DoubleDatabaseUser gets both
var user = container.GetInstance<DoubleDatabaseUser>();
user.Green.As<Database>().ConnectionString.ShouldBe("*green*");
user.Red.As<Database>().ConnectionString.ShouldBe("*red*");
}
}
public interface IDatabase { }
public class Database : IDatabase
{
public string ConnectionString { get; set; }
public Database(string connectionString)
{
ConnectionString = connectionString;
}
public override string ToString()
{
return string.Format("ConnectionString: {0}", ConnectionString);
}
}
public class InjectDatabaseByName : ConfiguredInstancePolicy
{
protected override void apply(Type pluginType, IConfiguredInstance instance)
{
instance.Constructor.GetParameters()
.Where(x => x.ParameterType == typeof(IDatabase))
.Each(param =>
{
// Using ReferencedInstance here tells StructureMap
// to "use the IDatabase by this name"
var db = new ReferencedInstance(param.Name);
instance.Dependencies.AddForConstructorParameter(param, db);
});
}
}
public class BigService
{
public BigService(IDatabase green)
{
DB = green;
}
public IDatabase DB { get; set; }
}
public class ImportantService
{
public ImportantService(IDatabase red)
{
DB = red;
}
public IDatabase DB { get; set; }
}
public class DoubleDatabaseUser
{
public DoubleDatabaseUser(IDatabase red, IDatabase green)
{
Red = red;
Green = green;
}
// Watch out for potential conflicts between setters
// and ctor params. The easiest thing is to just make
// setters private
public IDatabase Green { get; private set; }
public IDatabase Red { get; private set; }
}
}
答案 0 :(得分:0)
我在测试中使用的As<T>()
扩展方法不是BCL的一部分,这就是你找不到它的原因。如果您正在使用“应该”,则可以使用ShouldBeOfType<T>()
执行相同的操作,或者在进行比较之前将其正常投射。 Each()
扩展程序也是如此。