var sfId = window.sfdcPage.getEntityId().split('/');
var recId = sfId[sfId.length-1];
{!REQUIRESCRIPT("/soap/ajax/35.0/connection.js")}
{!REQUIRESCRIPT("/soap/ajax/35.0/apex.js")}
var myvar = sforce.apex.execute("cadarch.UnarchivePlanning","unarchive",{sourceId:recId});
window.alert(myvar);