KnockOut.js文本绑定客户端更改未更新ViewModel

Question

I have two dropdowns upon change will update a label. the label is bound to an observably field in my viewModel using text binding. However, when the label text is changed, the viewModel submitted to the server is not updated. I couldn't find related information from knockout website. Am I missing something?

HTML

       <select class="string-match-dropdown">
            <option value="*">contains</option>
            <option value="^">starts with</option>
            <option value="$">ends with</option>
            <option value="=">is exactly</option>
            <option value="@@">has value</option>
        </select>
        <select class="date-money-match-dropdown">
            <option value="eq">=</option>
            <option value="noteq"><></option>
            <option value="gt">></option>
            <option value="gteq">>=</option>
            <option value="lt"><</option>
            <option value="lteq">&lt;=</option>
        </select>
        <label class="match-label" data-bind='html: qualifier'></label>

JS

$('.date-money-match-dropdown').live('change', function () {
    $(this).parent().find('.match-label').html($(this).find('option:selected').text());
});

$('.string-match-dropdown').live('change', function () {
    $(this).parent().find('.match-label').html($(this).find('option:selected').text());
});

Answer 1

For this scenario you don't need to use jquery at all.

Because you already have an observable on your viewmodel qualifier you just need to use the value binding on your select s and Knockout will do the change handling for you:

<select class="string-match-dropdown" data-bind='value: qualifier'>
    <option value="*">contains</option>
    <option value="^">starts with</option>
    <option value="$">ends with</option>
    <option value="=">is exactly</option>
    <option value="@@">has value</option>
</select>
<select class="date-money-match-dropdown" data-bind='value: qualifier'>
    <option value="eq">=</option>
    <option value="noteq"><></option>
    <option value="gt">></option>
    <option value="gteq">>=</option>
    <option value="lt"><</option>
    <option value="lteq">&lt;=</option>
</select>
<label class="match-label" data-bind='html: qualifier'></label>

Demo JSFiddle.