随机数的生成

var produce = function ()
{
    var array1 = "ABCDEFGHIJKMNPQRSTUVWXYZ".split ("");
    var array2 = "123456789".split ("");
    var str = "A";
    for ( var i = 0; i < 4; i++)
    {
        str += array2[Math.floor (Math.random () * array2.length)];
    }
    for ( var i = 0; i < 4; i++)
    {
        str += array1[Math.floor (Math.random () * array1.length)];
    }
    var reg = /^\d$/;
    var now = new Date;
    var m = now.getMonth () + 1;
    var d = now.getDate();
    m = reg.test(m) ? "0" + m : m;
    d = reg.test(d) ? "0" + d : d;
    str += now.getFullYear () + m + d;
    return str;
};

$(".ordernum").html(produce ());