打字效果的JS

 <input type="text" value="瑞纳" id="Search1_txt_SerchKey"  onblur="shownew(true)" onfocus="shownew(false)" onclick="shownew(false)" />

<!--网站公告：<a id="HotNews" href="" target="_blank"></a>-->
<script language="JavaScript" type="text/javascript">
<!--
    var NewsTime = 5000;  //每条新闻的停留时间
var TextTime = 150;    //新闻标题文字出现等待时间，越小越快

    var newsi = 0;
    var txti = 0;
    var txttimer;
    var newstimer;

    var newstitle = new Array();  //新闻标题
var newshref = new Array();    //新闻链接

    newstitle[0] = "奎宇工作室最新web应用";
    newshref[0] = "http://www.kuiyu.net";

    newstitle[1] = "奎宇浏览器";
    newshref[1] = "http://www.kuiyu.net";

    newstitle[2] = "市场竞争日趋激烈 本周6款新车即将上市";
    newshref[2] = "http://www.kuiyu.net";

    newstitle[3] = "汽车交强险对外开放 法规年内有望出台";
    newshref[3] = "http://www.kuiyu.net";

    newstitle[4] = "奎宇工作室专业web开发";
    newshref[4] = "http://www.kuiyu.net";

    function shownew(run) {
        if (run == false) {
            document.getElementById("Search1_txt_SerchKey").value = "";//清空输入框
            clearInterval(txttimer);
            clearInterval(newstimer);
            return;          
        }
            
            var endstr = "_"
            hwnewstr = newstitle[newsi];
            newslink = newshref[newsi];
            if (txti == (hwnewstr.length - 1)) { endstr = ""; }
            if (txti >= hwnewstr.length) {
                clearInterval(txttimer);
                clearInterval(newstimer);
                newsi++;
                if (newsi >= newstitle.length) {
                    newsi = 0
                }
                newstimer = setInterval("shownew('run')", NewsTime);
                txti = 0;
               
            }
            clearInterval(txttimer);
            //    document.getElementById("HotNews").href = newslink;
//    document.getElementById("HotNews").innerHTML = hwnewstr.substring(0, txti + 1) + endstr;
            document.getElementById("Search1_txt_SerchKey").value = hwnewstr.substring(0, txti + 1) + endstr;
            txti++;
            txttimer = setInterval("shownew('run')", TextTime);
        }
        shownew(true);
//-->
</script>