Take an entire DataTable object and create a CSV output from it, skipping filtered rows, but showing all the columns (except the ones you select specifically in the code to not show).

datatables_export.js

// Setup: Just send your DataTables object (oTable) into this function onclick on some button.


// Inspired by this source, but more or less completely re-written because we need to respect filters on tables
// http://datatables.net/forums/discussion/11984/simple-csv-export-with-jquery-php
function table2csv(oTable) {
    var csv = '';
    var text;
    var headers = [];
    var columns = [];
    var rows = [];
    var skip = [2,12,14]; // Columns we do not want to include (used for search, filtering and sorting)
    var separator = ";";

    // Get header names
    var tr = oTable.dataTableSettings[0].aoColumns;
    
    $.each(tr, function(i,v) {
        
        // Skip certain column headers we just use for search, filtering and sorting
        if ( $.inArray(i,skip) == -1 ) {

            var th = v.sTitle;

            // Remove select-blocks entirely from header, we don't want it in the export - but use it's first child as the heading
            if ( th.indexOf("select") !== -1 ) {

                text = $( th ).find("option:first-child").text();

            } else {

                text = th;
            }
            
            // The finaliced header put inside quotes for Excel importing (but not really needed)
            var header = '"' + text.replace(":","") + '"';

            // actually datatables seems to copy my original headers so there is an amount of TH cells which are empty
            if (text != "") {
                headers.push(header);
            }

        }

    });

    // Add all the header columns to the main CSV-code/text block (will use that more later)
    csv += headers.join(separator) + "\n\n";

    // Fetch only visible rows (respect active filters)
    var all_rows = oTable._('tr', {"filter":"applied"});

    $.each( all_rows, function(index,elem) {

        // For each row, find each column
        $.each( elem, function(i,e) {
            
            // Skip certain column headers we just use for search, filtering and sorting
            if ( $.inArray(i,skip) == -1 ) {

                // Our popup messes up the result, since it's the only one containing a div treat it differently
                if ( e.indexOf("div") !== -1 ) {

                    text = $( e ).find("a:first-child").text();

                } else {

                    text = e.replace(/<br>/g,", "); // Linebreaks needs to be replaced by commas
                    
                    // All the other fields just need to get stripped from tags and whitespaces
                    text = strip_tags(text);
                    text = text.trim();
                    text = text.replace(/\n/g,"");
                    text = text.replace(/\r/g,"");
                    text = text.replace(/\t/g,"");
                    text = text.replace(/,$/, ""); // Remove trailing commas
                }

                // Switch semicolons to normal colons so our CSV doesn't get ruined by user content
                text = text.replace(new RegExp(separator,"g"), "");
                
                columns.push( text );

            }

        });

        // Join the columns from this row into our row array, then empty the column array so we can go onto next table row
        rows.push( columns.join(separator) );
        columns = [];

    });

    // Add all the rows to the main CSV-code/text block
    csv += rows.join("\n");

    // Kill the CSV-div (for showing) if it exists
    if($('.csv-data').length) $('.csv-data').remove();
    
    // Create the div and show the CSV output
    $('body').append('<div class="csv-data" style="width:100%;height:100%;background-color:hsla(1,0%,0%,0.6);position:absolute;top:0;z-index:1;"><form style="margin:10em auto;width:75%;height:75%;background-color:white;"><textarea style="width:100%;height:100%;" name="csv">'+csv+'</textarea></form></div>');

}
 
function strip_tags(html) {
    var tmp = document.createElement("div");
    tmp.innerHTML = html;
    return tmp.textContent||tmp.innerText;
}