I have an array of elements assembled by:
timeArray = [];
$('.time_select').each(function(i, selected) {
timeArray[i] = $(selected).val();
});
where .time_select is a class on a group of different HTML select tags.
What I'd like to do is count the number of times a specific value occurs in timeArray. Strangely enough, I haven't found any concise solution... surely there's a simple way to do this?
You should try abstracting that into a function using the (under-used) $.each() function, I'd say.
function countElement(item,array) {
var count = 0;
$.each(array, function(i,v) { if (v === item) count++; });
return count;
}
Then you can use it like so:
var a = ['foo','bar','foo'];
var b = countElement('foo',a); // should return 2
timeArray = [];
occurs = {};
$('.time_select').each(function(i, selected) {
timeArray[i] = $(selected).val();
if (occurs[timeArray[i]] != null ) { occurs[timeArray[i]]++; }
else {occurs[timeArray[i]] = 1; }
});
JS doesn't have many built-in functions for dealing with arrays. This is about as concise as it gets:
var count = 0;
for (var i = 0; i < timeArray.length; i++) {
count += (timeArray[i] == targetValue);
}
If you're willing to incur the overhead of an additional library, then underscore.js supplies a number of handy utility functions. Using underscore.js, the above code can be simplified to:
_(timeArray).reduce(function(m, num) {return m + (num == targetValue);}, 0);
You need grouping. See jQuery Table Plugin with Group By
