日期控件鼠标离开如何消失

// JavaScript Documentvar str = "";document.writeln("<div id=\"_contents\" style=\"padding:6px; background-color:#E3E3E3; font-size: 12px; border: 1px solid #777777;  position:absolute; left:?px; top:?px; width:?px; height:?px; z-index:1; visibility:hidden\">");str += "\u65f6<select name=\"_hour\">";for (h = 0; h <= 9; h++) {    str += "<option value=\"0" + h + "\">0" + h + "</option>";}for (h = 10; h <= 23; h++) {    str += "<option value=\"" + h + "\">" + h + "</option>";}str += "</select> \u5206<select name=\"_minute\">";for (m = 0; m <= 9; m++) {    str += "<option value=\"0" + m + "\">0" + m + "</option>";}for (m = 10; m <= 59; m++) {    str += "<option value=\"" + m + "\">" + m + "</option>";}str += "</select> \u79d2<select name=\"_second\">";for (s = 0; s <= 9; s++) {    str += "<option value=\"0" + s + "\">0" + s + "</option>";}for (s = 10; s <= 59; s++) {    str += "<option value=\"" + s + "\">" + s + "</option>";}str += "</select> <input name=\"queding\" type=\"button\" onclick=\"_select()\" value=\"\u786e\u5b9a\" style=\"font-size:12px\" /></div>";document.writeln(str);var _fieldname;function _SetTime(tt) {    _fieldname = tt;    var ttop = tt.offsetTop;    //TT控件的定位点高    var thei = tt.clientHeight;    //TT控件本身的高    var tleft = tt.offsetLeft;    //TT控件的定位点宽    while (tt = tt.offsetParent) {        ttop += tt.offsetTop;        tleft += tt.offsetLeft;    }    document.all._contents.style.top = ttop + thei + 4;    document.all._contents.style.left = tleft;    document.all._contents.style.visibility = "visible";}function _select() {    _fieldname.value = document.all._hour.value + ":" + document.all._minute.value + ":" + document.all._second.value;    document.all._contents.style.visibility = "hidden";}