JS编写选择年份控件

/**//***********************************
* 简单时间控件： version 1.0
* 作者：Joe
* 时间：20015-08-03
*
* 使用说明：
* 首先把本控件包含到页面
* <script src="XXX/setTime.js" type="text/javascript"></script>
* 控件调用函数：_SetTime(field)
* 例如 <onclick="_SetTime(this)"/>
************************************/
var MyDate = new Date();
var CurrentYear = MyDate.getFullYear();
var StartYear = CurrentYear - 7;
var EndYear = CurrentYear + 7;
var Count = 0;

var str = "";
document.writeln("<div id = \"_top\" style=\"text-align:center;vertical-align:middle;background-color:#CC0000;padding:6px;border: 2px solid #CC0000; position:absolute; z-index:1;width:247px;height:20px;visibility:hidden\">");
str += "<img id=\"img_left\" alt=\"\" src=\"../images/left.ico\" width=\"16px\"  onclick=\"Left_getTdValue()\" onmouseover=\"mousemove(this)\"/> &nbsp;";
str += "<label  id=\"title\" style=\"color:White;font-family: 微软雅黑; font-size: small;\">当前年份: </label>";
str += "<label  id=\"title2\" style=\"color:White;font-family: 微软雅黑; font-size: small;\" onclick=\"c_year()\" onmouseover=\"mousemove(this)\">" + CurrentYear + "</label> &nbsp;";
str += "<img id=\"img_right\" alt=\"\" src=\"../images/right.ico\" width=\"16px\"  onclick=\"Right_getTdValue()\" onmouseover=\"mousemove(this)\" />";
str += "</div>";
str += "<div id=\"_contents\" style=\"background-color:#E4E4E4;padding:6px;border: 2px solid #CC0000; position:absolute; z-index:1;width:247px;visibility:hidden\">";
str += "<table id=\"tab\">";
for (var h = StartYear; h <= EndYear; h++)
{
    if (Count == 0) {
        str += "<tr class=\"TR-main\">";