Test if element already has jQuery datepicker

1) If the code throws an error when trying to open the datepicker, you can put the code into try..catch

2) You can set some data to the input field when initializing the datepicker

$("#someElement").data("datepicker-initialized", true);

3) You can use the data stored by datepicker plugin

if($("#someElement").data("datepicker") != null){
   // datepicker initialized
}

or

if($.data($('#someElement').get(0), 'datepicker')){
   // datepicker initialized
}

4) datepicker internally uses a function _getInst

if($.datepicker._getInst($('#someElement')[0]) != null){}

the method does almost the same as example 3.

Couldn't find any better solution.

Wow can't believe I missed this one. Line 108 of ui.datepicker.js:

/* Class name added to elements to indicate already configured with a date picker. */
markerClassName: 'hasDatepicker',

So I just need to test for hasClass('hasDatepicker'). This seems like the most straightforward way. Furthermore, this statement checks whether the datepicker is currently opened (for anyone who is interested):

if ($("#ui-datepicker-div").is(":visible") && $("#ui-datepicker-div").html() != "") {
    // datepicker is open. you need the second condition because it starts off as visible but empty
}

One basic solution is to set an attribute at time of the datepicker attachment and then test for that:

$("#someElement").mask("9?9/99/9999")
.datepicker({showOn: 'button', buttonText:'Click here to show calendar', duration: 'fast', buttonImageOnly: true, buttonImage: /images/calicon.gif' })
.attr("data-calendar", "true");

Then you could do:

if ($(selection).attr("data-calendar") == "true")
    $(selection).datepicker("show");

Is there a more direct way?