Constuctor with GroupBy Problem

[Samnang Chhun]

Hi,

 

I'm just getting to work with iBatis.Net in my C# project. I found a problem
when I call constructor with groupBy in my ResultMap. What have I done
something wrong?

 

<resultMap id="personResult" class="Person" groupBy="_id">

      <constructor>

          <argument argumentName="id" column="id"/>

      </constructor>

      <result property="_name" column="name" />

      <result property="_address" resultMapping="Person.addressResult"/>

</resultMap>

 

<resultMap id="addressResult" class="Address">

      <result property="_type" column="type" />

      <result property="_value" column="value" />

</resultMap>

 

My error is : System.NullReferenceException: Object reference not set to an
instance of an object.

 

 

Cheers,

Samnang