function isPlaceHolder() {
    var input = document.createElement("input");
    return "placeholder" in input;
}
if (!isPlaceHolder()) {
    function placeHolder(obj) {
        if (!obj) { return; }
        this.input = obj;
        this.label = document.createElement("label");
        this.label.innerHTML = obj.getAttribute("placeholder");
        this.label.className = "placeholder";
        if (obj.value != "") {
            this.label.style.display = "none";
        }
        this.init();
    }
    placeHolder.prototype = {
        getxy: function (obj) {
            if (document.documentElement.getBoundingClientRect) {
                var st = document.documentElement.scrollTop || document.body.scrollTop,
                    sl = document.documentElement.scrollLeft || document.body.scrollLeft,
                    ct = document.documentElement.clientTop || document.body.clientTop,
                    cl = document.documentElement.clientLeft || document.body.clientLeft
                //alert(obj.offsetLeft);
                //return { left: obj.getBoundingClientRect().left + sl - cl, top: obj.getBoundingClientRect().top + st - ct };
                return { left: obj.offsetLeft, top: obj.offsetTop };
            }
            else {
                var l = t = 0;
                while (obj) {
                    l += obj.offsetLeft;
                    t += obj.offsetTop;
                    obj = obj.offsetParent;
                }
                return { top: t, left: l }
            }
        },
        getwh: function (obj) {
            return { w: obj.offsetWidth, h: obj.offsetHeight }
        },
        setStyles: function (obj, styles) {
            for (var p in styles) {
                obj.style[p] = styles[p] + 'px';
            }
        },
        init: function () {
            var label = this.label,
                input = this.input,
                xy = this.getxy(input),
                wh = this.getwh(input);
            this.setStyles(label, { 'width': wh.w, 'height': wh.h, 'lineHeight': wh.h, 'left': xy.left, 'top': xy.top });
            //document.body.appendChild(this.label);
            input.offsetParent.appendChild(this.label);
            //alert(input.offsetParent);
            //label.setAttribute("for",input.id);
            label.onclick = function () {
                this.style.display = "none";
                input.focus();
            }
            input.onfocus = function () {
                label.style.display = "none";
            };
            input.onblur = function () {
                if (this.value == "") {
                    label.style.display = "";
                }
            };
        }
    }
    function init() {
        var inps = document.getElementsByTagName("input");
        for (var i = 0, len = inps.length; i < len; i++) {
            if (inps[i].getAttribute("placeholder")) {
                new placeHolder(inps[i]);
            }
        }
        var areas = document.getElementsByTagName("textarea");
        for (var i = 0, len = areas.length; i < len; i++) {
            if (areas[i].getAttribute("placeholder")) {
                new placeHolder(areas[i]);
            }
        }
    }
    window.onload = init;
}