Javascript mktime : Date and Time : PHP functions in JavaScript JAVASCRIPT TUTORIALS

function mktime() {
    // Get UNIX timestamp for a date  
    // 
    // version: 901.2514
    // discuss at: http://phpjs.org/functions/mktime
    // +   original by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +   improved by: baris ozdil
    // +      input by: gabriel paderni 
    // +   improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +   improved by: FGFEmperor
    // +      input by: Yannoo
    // +   bugfixed by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +      input by: jakes
    // +   bugfixed by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // +   bugfixed by: Marc Palau
    // *     example 1: mktime(14, 10, 2, 2, 1, 2008);
    // *     returns 1: 1201871402
    // *     example 2: mktime(0, 0, 0, 0, 1, 2008);
    // *     returns 2: 1196463600
    // *     example 3: make = mktime();
    // *     example 3: td = new Date();
    // *     example 3: real = Math.floor(td.getTime()/1000);
    // *     example 3: diff = (real - make);
    // *     results 3: diff < 5
    // *     example 4: mktime(0, 0, 0, 13, 1, 1997)
    // *     returns 4: 883609200
    // *     example 5: mktime(0, 0, 0, 1, 1, 1998)
    // *     returns 5: 883609200
    // *     example 6: mktime(0, 0, 0, 1, 1, 98)
    // *     returns 6: 883609200
    
    var no, ma = 0, mb = 0, i = 0, d = new Date(), argv = arguments, argc = argv.length;

    if (argc > 0){
        d.setHours(0,0,0); d.setDate(1); d.setMonth(1); d.setYear(1972);
    }
 
    var dateManip = {
        0: function(tt){ return d.setHours(tt); },
        1: function(tt){ return d.setMinutes(tt); },
        2: function(tt){ var set = d.setSeconds(tt); mb = d.getDate() - 1; return set; },
        3: function(tt){ var set = d.setMonth(parseInt(tt)-1); ma = d.getFullYear() - 1972; return set; },
        4: function(tt){ return d.setDate(tt+mb); },
        5: function(tt){ return d.setYear(tt+ma); }
    };
    
    for( i = 0; i < argc; i++ ){
        no = parseInt(argv[i]*1);
        if (isNaN(no)) {
            return false;
        } else {
            // arg is number, let's manipulate date object
            if(!dateManip[i](no)){
                // failed
                return false;
            }
        }
    }

    return Math.floor(d.getTime()/1000);
}