title: Dojo date constraint to a single day per month
body: <p>Is it possible to make a constraint to only allow the first day of each much a valid option? I'd like to grey out all other dates but I can't seem to find out how to do this? I'm trying to find something useful in Dojo's so called documentation but no luck so far. I understand sending a date to the min and max but that doesn't really solve my issue. </p>
  
  <p><a href="http://dojotoolkit.org/reference-guide/1.7/dijit/form/DateTextBox.html" rel="nofollow">http://dojotoolkit.org/reference-guide/1.7/dijit/form/DateTextBox.html</a></p>
  
  <p>This is what I've been playing with:</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>dojo.require("dijit.form.DateTextBox");</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;link href="http://ajax.googleapis.com/ajax/libs/dojo/1.9.3/dojo/resources/dojo.css" rel="stylesheet" /&gt;
  &lt;link href="http://ajax.googleapis.com/ajax/libs/dojo/1.9.3/dijit/themes/claro/claro.css" rel="stylesheet" /&gt;
  &lt;script src="//ajax.googleapis.com/ajax/libs/dojo/1.9.3/dojo/dojo.js" djConfig="parseOnLoad:true"&gt;&lt;/script&gt;
  
  &lt;body class="claro"&gt;
    &lt;div name="BeginDate" type="text" data-dojo-type="dijit.form.DateTextBox" constraints="{selector:'date',min:'2012'}" datePattern="dd/MMM/yy" value="@Model.BeginDate"&gt;
      &lt;script type="dojo/connect" args="newValue" data-dojo-event="onChange"&gt;
      &lt;/script&gt;
    &lt;/div&gt;</code></pre>
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