纯js实现的论坛常用的运行代码的效果_javascript技巧

//Scripts runcode for BBS ver 2008-06-30, by Bound0(bound0@veryhman.com)

//First published at http://bbs.blueidea.com

//An example: http://bbs.veryhman.com/showtopic-20094.aspx

function runCode(which) {

var p=which.parentNode;

var os=p.getElementsByTagName("textarea");

if(os.length==0)return;

var o=os[0];

var winname = window.open('', "_blank", '');

winname.document.open('text/html', 'replace');

winname.opener = null;

winname.document.write(o.value);

winname.document.close();

}

function saveCode(which) {

var p=which.parentNode;

var os=p.getElementsByTagName("textarea");

if(os.length==0)return;

var o=os[0];

var winname = window.open('', '_blank', 'top=10000');

winname.document.open('text/html', 'replace');

winname.document.write(o.value);

winname.document.execCommand('saveas','','code.htm');

winname.close();

}

function copycode(which) {

var p=which.parentNode;

var os=p.getElementsByTagName("textarea");

if(os.length==0)return;

var o=os[0];

var is_ie = (userAgent.indexOf('msie') != -1 && !is_opera) && userAgent.substr(userAgent.indexOf('msie') + 5, 3);

if(is_ie && o.style.display != 'none') {

var rng = document.body.createTextRange();

rng.moveToElementText(o);

rng.scrollIntoView();

rng.select();

rng.execCommand("Copy");

rng.collapse(false);

}

}

function text(e)

{

var t = "";

e = e.childNodes || e;

for ( var j = 0; j < e.length; j++ )

{

if(e[j].nodeType != 1){t+=e[j].nodeValue}

else

{

var k=e[j].nodeName;

if(k=='BR'||k=='P'){t+='\r\n'}

t+=text(e[j].childNodes)

}

}

return t;

}

function preCode(which) {

var p=which.parentNode;

var os=p.getElementsByTagName("textarea");

if(os.length==0)return;

var o=os[0];

var osv=p.getElementsByTagName("div");

if(osv.length==0)return;

var ov=osv[0];

var c=''

if(typeof(ov.innerText)!="undefined"){c=ov.innerText}else{c=text(ov)}

o.value=c

}

(function(){var s=document.getElementsByTagName("script");preCode(s[s.length-1])})()