In a form field has the input:

<input type = "text" class = "<PHP print $estilo_caixa;?>" id = "datepicker" name = "dt_fundacao" size = "12" maxlength = "10" placeholder = "Data Foundation">

After the test input as if the field was completed in Javascript and also treat on a select in PHP?

How to put a mask on input (__ / __ / ____) the datepicker?