Need a smarter jQuery table sort function

Question

I'm using the following code from another stackoverflow question:

$('th').click(function(){
    var table = $(this).parents('table').eq(0)
    var rows = table.find('tr:gt(0)').toArray().sort(comparer($(this).index()))
    this.asc = !this.asc
    if (!this.asc){rows = rows.reverse()}
    for (var i = 0; i < rows.length; i++){table.append(rows[i])}
})
function comparer(index) {
    return function(a, b) {
        var valA = getCellValue(a, index), valB = getCellValue(b, index)
        return $.isNumeric(valA) && $.isNumeric(valB) ? valA - valB : valA.toString().localeCompare(valB)
    }
}
function getCellValue(row, index){ return $(row).children('td').eq(index).text() }

table, th, td {
    border: 1px solid black;
}
th {
    cursor: pointer;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<table>
    <tr><th>Country</th><th>Pick</th><th>Size</th></tr>
    <tr><td>France</td><td>2</td><td>25</td></tr>
    <tr><td><a href=#>spain</a></td><td>-</td><td></td></tr>
    <tr><td>Lebanon</td><td>1</td><td>-17</td></tr>
    <tr><td>Argentina</td><td>DH</td><td>100</td></tr>
    <tr><td>USA</td><td>-</td><td>-6</td></tr>
</table>

which works great for most data. My problem is with the "Pick" column. I'd like it to sort so that it looks like this:

Pick
1
2
DH
-
-

I'm assuming it's the comparer function that I'd need to modify. How do I modify this so that it basically always puts "-" at the bottom of the table and then sorts numbers from lowest to highest with "DH" right below the numbers? Is that a pretty simple addition to the function? Or is it a ton of custom code?

Answer 1

You can just add some custom logic to your comparer.

The only part I changed in the snippet below is the function comparer(index) contents.

$('th').click(function(){
    var table = $(this).parents('table').eq(0)
    var rows = table.find('tr:gt(0)').toArray().sort(comparer($(this).index()))
    this.asc = !this.asc
    if (!this.asc){rows = rows.reverse()}
    for (var i = 0; i < rows.length; i++){table.append(rows[i])}
})
function comparer(index) {
    return function(a, b) {
        var valA = getCellValue(a, index), valB = getCellValue(b, index);
        
        if (valA === "-") valA = Number.MAX_SAFE_INTEGER;
        if (valB === "-") valB = Number.MAX_SAFE_INTEGER;
        if (valA === "DH") valA = Number.MAX_SAFE_INTEGER - 1;
        if (valB === "DH") valB = Number.MAX_SAFE_INTEGER - 1;

        return $.isNumeric(valA) && $.isNumeric(valB) ? valA - valB : valA.toString().localeCompare(valB)
    }
}
function getCellValue(row, index){ return $(row).children('td').eq(index).text() }

table, th, td {
    border: 1px solid black;
}
th {
    cursor: pointer;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<table>
    <tr><th>Country</th><th>Pick</th><th>Size</th></tr>
    <tr><td>France</td><td>2</td><td>25</td></tr>
    <tr><td><a href=#>spain</a></td><td>-</td><td></td></tr>
    <tr><td>Lebanon</td><td>1</td><td>-17</td></tr>
    <tr><td>Argentina</td><td>DH</td><td>100</td></tr>
    <tr><td>USA</td><td>-</td><td>-6</td></tr>
</table>