把手：有条件地添加属性

Question

I'm trying to render a select element with options, like this

<select dropdown multiple class="dropdown" name="color">
        {{#each colors}}
            <option value="{{value}}" {{isSelected parentColor id}}>{{title}}></option>
        {{/each}}
</select>

I'm using the following handlebars helper

Handlebars.registerHelper('isSelected', function(input, color) {
    return input === color ? 'selected' : '';
});

The problem is that the selected attribute doesn't show up on any of the option element, but when I place a console.log in the handlebar helper I do see that one matches (input === color === true). Any ideas what I do wrong here ?

Answer 1

This is a working example of what is described,

http://jsfiddle.net/rtLGR/

hbs

<h1>Handlebars JS Example</h1>
<script id="some-template" type="text/x-handlebars-template"> 

    <select dropdown multiple class="dropdown" name="color">
        {{#each colors}}
            <option value="{{value}}" {{isSelected parentColor id}}>{{title}}</option>
        {{/each}}
</select>
</script>

js

var source = $("#some-template").html();
var template = Handlebars.compile(source);

var data = {
    colors: [
        {id:1,value:1,title:"red",parentColor:2},
        {id:2,value:2,title:"green",parentColor:2},
        {id:3,value:3,title:"blue",parentColor:1}
    ]
};


Handlebars.registerHelper('isSelected', function (input, color) {
    return input === color ? 'selected' : '';
});

$('body').append(template(data));