在Fluent NHibernate中存储一个对象[]作为列 [英] Storing an object[] as column in Fluent NHibernate

问题描述

我有以下（部分）模型：

 类LogMessage {
字符串格式; 
 object [] args; 
 
  

我想存储 args [] 作为表中的单个列，事先了解格式参数通常是可序列化的，或者可以被转换为字符串先验。

我不想存储格式化的消息，我想分开存储格式和参数（这有几个优点）。

我怎么能告诉流利的NHibernate使用BLOB类型来存储该列，并执行简单的二进制序列化/反序列化时持久的实体？

> Map（x => x.Args）.CustomType< ObjectArrayType>（）;
$ b $ class ObjectArrayType：IUserType
{
public object NullSafeGet（IDBReader reader，string [] names，object owner）
{
byte [] bytes = NHibernateUtil.BinaryBlob.NullSafeGet（reader，names [0]）;
返回反序列化（字节）;

$ b $ public void NullSafeSet（IDBCommand cmd，object value，int index）
{
var args =（object []）value;
NHibernateUtil.BinaryBlob.NullSafeSet（cmd，Serialize（args），index）;


类型返回类型
{
get {return typeof（object []）; }

$ b $ public SqlType [] SqlTypes
{
get {return new [] {SqlTypeFactory.BinaryBlob}}
}
}


I have the following (partial) model:

class LogMessage{
    string Format;
    object[] args;
}

I want to store args[] as a single column in the table, taking advance of the fact that format arguments are generally serializable or can be converted to a string a priori.

I don't want to store the formatted message, I want to separately store format and args (this has several advantages).

How can I tell Fluent NHibernate to use a BLOB type to store that column and perform simple binary serialization/deserialization when persisting the entity?

解决方案

Map(x => x.Args).CustomType<ObjectArrayType>();

class ObjectArrayType : IUserType
{
    public object NullSafeGet(IDBReader reader, string[] names, object owner)
    {
        byte[] bytes = NHibernateUtil.BinaryBlob.NullSafeGet(reader, names[0]);
        return Deserialize(bytes);
    }

    public void NullSafeSet(IDBCommand cmd, object value, int index)
    {
        var args = (object[])value;
        NHibernateUtil.BinaryBlob.NullSafeSet(cmd, Serialize(args), index);
    }

    public Type ReturnType
    {
        get { return typeof(object[]); }
    }

    public SqlType[] SqlTypes
    {
        get { return new [] { SqlTypeFactory.BinaryBlob } }
    }
}

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