Making Javascript-search-function fast

Question

Hello everyone,

I made a little search-function with javascript to look for a string in a table: There are "tr"s that simply contain a number as an id and there are "tr"s that contain "childNode+idOfParentNode" as an id (e.g.:

<tr id="1"> ... </tr>
<tr id="childNode1"> ... </tr>

Now I want to look through the table, see if a giving string or part of it matches the content of the parent-"tr". If that is not the case I want the parent-"tr" and its childNode-"tr"s to be hidden (or collapsed). And I want them being shown if the string or part of it matches. Here is my function:

// inputFieldId := Id of the inputField that contains the search-String
// tableId := Id of the table to be searched
function searchTable( inputFieldId, tableId ){
    var inputField = document.getElementById( inputFieldId );
    var input = inputField.value.toUpperCase();
    var countRows   = jQuery( '#' + tableId + ' tr' ).length;
    jQuery('#loader').css( "visibility", "visible" );
    var hideChildren = false;
    var childId = -1;
    var parentId = -1;

    for( var i = 1; i <= countRows; i++ ){
        var trsId = jQuery('#' + tableId + ' tr:nth-child('+i+')' ).attr('id');
        // I am only looking for <tr> that are not "childnodes"
        if( trsId.indexOf( "childNode") == -1 ){
            var firstTd = jQuery('#' + tableId + ' tr:nth-child('+i+') td:nth-child(1)' );
            var firstTdValue = firstTd.text();
            if( firstTdValue.indexOf( input ) == -1 ){
                hideChildren = true;
                childId = trsId;
                parentId = i;
                jQuery('#' + tableId + ' tr:nth-child('+i+')' ).children('td').css("visibility", "collapse");
                jQuery('#' + tableId + ' tr:nth-child('+i+')' ).css("visibility", "collapse");
            }
            else{
                hideChildren = false;
                childId = trsId;
                parentId = i;
                jQuery('#' + tableId + ' tr:nth-child('+i+')' ).children('td').css("visibility", "visible");
                jQuery('#' + tableId + ' tr:nth-child('+i+')' ).css("visibility", "visible");
            }
        }
        else{
            childNodeId = "childNode"+childId;
            if( hideChildren && trsId == childNodeId && parentId > -1 ){
                jQuery('#' + tableId + ' tr:nth-child('+i+')' ).children('td').css("visibility", "collapse");
                jQuery('#' + tableId + ' tr:nth-child('+i+')' ).css("visibility", "collapse");
            }
            else{
                jQuery('#' + tableId + ' tr:nth-child('+i+')' ).children('td').css("visibility", "visible");
                jQuery('#' + tableId + ' tr:nth-child('+i+')' ).css("visibility", "visible");
            }
        }
    }
    jQuery('#loader').css( "visibility", "hidden" );
}

Seriously, this works fine, but it takes FOREVER!!! especially if it is a larger table, so I was wondering if someone saw a way to make my function faster and more efficient.

Thnx in advance :)

=========================================================================

EDIT: I made it work ... it now looks like this and works wonderfully :)

function searchTable( inputFieldId, tableId ){
    jQuery('#loader').show();
    var input = jQuery('#'+inputFieldId).val().toUpperCase();
    var parentId = -1

    jQuery('#' + tableId + ' tr').each( function(i) {
        var thiss = jQuery(this);
        var showP = false;
        var showC = false;
        if (thiss.attr('id').indexOf('child') < 0) { // parent
            parentId = thiss.attr('id');
            showP = !(thiss.find('td:first').text().indexOf( input ) < 0);
            thiss.toggle( showP );
        }
        else{ // childNode
            var childId = "childNode"+parentId;
            var parent = jQuery('#'+tableId+' tr#'+parentId+':visible').length;
            showC = !(thiss.attr('id') == childId && parent < 1);
            thiss.toggle( showC );
        }        
    });
    jQuery('#loader').css( "visibility", "hidden" );
}

Thank you :)

Answer 1

1) Cache the selector that you create multiple times. Then use the variable from then on in.

var $rows = jQuery('#' + tableId + ' tr:nth-child('+i+')' );

$rows.children()...

2) to get direct children you can use '>' in your selector

 var $rows = jQuery('#' + tableId + '>tr:nth-child('+i+')' );

Answer 2

var rowsCache = null;
function searchTable( inputFieldId, tableId ){

    var input = String(jQuery("#inputFieldId").val()).toUpperCase();

    if (rowsCache==null)
     rowsCache = jQuery( '#' + tableId + ' tr');

    jQuery('#loader').css( "visibility", "visible" );

    //if there are many rows is faster --
    //for(var i = (countRows-1); i >= 0; i--) {

    jQuery(rowsCache).each(function() {
     if ((jQuery(this).html().indexOf(input)!=-1)
     {
      ...
     }
    });
    jQuery('#loader').css( "visibility", "hidden" );
}

Answer 3

It would be easier if the parents (and children) had classes identifying them as such, but you can get by with the ids if need be. I'm using $ instead of jQuery, but you can change that back if you need to.

// inputFieldId := Id of the inputField that contains the search-String
// tableId := Id of the table to be searched
function searchTable( inputFieldId, tableId ){
    var input = $('#' + inputFieldId).text().ToUpperCase();

    $('#loader').show();

    $('#' + tableId + ' tr').each( function(i) {
         var $this = $(this);
         var show = false;
         //  if ($this.hasClass('parent')) {  // would be nice
         if ($this.attr('id').indexOf('child') < 0) { // parent
             // note that text() here is the combined texts of all tds
             // adjust with :first if you really want to check only the first
             show = !($this.find('td').text().indexOf( input ) < 0);
         }
         $this.toggle( show );
    });

    $('#loader').hide();
}