json格式的日期格式化

function formatterdate(val) {
    if (val != null) {
        var re = /-?\d+/;
        var m = re.exec(val);
        var date = new Date(parseInt(m[0]));
        var y = date.getFullYear();
        var m = date.getMonth() + 1;
        m = m < 10 ? ('0' + m) : m;
        var d = date.getDate();
        d = d < 10 ? ('0' + d) : d;
        return y + '-' + m + '-' + d;
    }
}