As other users have already mentioned, "format" not a standard method of a Date object. You can do this without using any format (even if they are)
var t_sdate = "6/1/2012"; var sptdate = String(t_sdate).split("/"); var months = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec']; var myMonth = sptdate[0]; var myDay = sptdate[1]; var myYear = sptdate[2]; var combineDatestr = myDay + " " + months[myMonth - 1] + " " + myYear; alert(combineDatestr);
Jsfiddle demo
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