我可以使用Backbone.ModelBinder将选择框选项文本绑定到模型吗？

Question

I have an edit form set up in my Backbone app that populates with model data. I currently have it working without ModelBinder but want to switch over to ModelBinder.

I have a select box where the value maps to an id in the model, and the selected option text should map to a string field on the model. The user has the option of populating the model from the dropdown which will fill in the placeId and placeName or using a textbox to only fill in the placeName.

My question is how do I get this - $("#placeName option:selected").text() into the placeName selector?

Here is my model and bindings object:

// The Place Model
App.Models.Place = Backbone.Model.extend({
    defaults: {
          placeName: "",
          placeId: ""
  }
});

// Backbone Model Binder bindings
   bindings: {
       placeName:[
           {selector: '$("#placeName option:selected").text()'}, 
           {selector: '#textInputPlaceName'}] ,
    placeId:'[name=placeName]'
}

Here is the HTML. In the UI there is a checkbox for selecting either the dropdown or the input field

<select id="placeName" name="placeName" class="inline">
        <option value="0" selected="selected"></option>
        <option value="444">exit 1</option>
        <option value="555">exit 2</option>
        <option value="666">exit 3</option>
</select>
<input id="textInputPlaceName" name="textInputPlaceName class="inline" disabled>

Here's the same code in a fiddle: http://jsfiddle.net/kDBvQ/

Answer 1

I ended up setting and retrieving the value in a function outside of the modelBinder bindings. I probably could have used a converter, but it was more simple to do it without.