这个东西是在线写 js 脚本的时候，用来即时查错的东西！
也就是，当发现所编写的脚本有问题的时候会有相应的提示，并且在源代码框中高亮标示出错行，方便除错
<HTML><HEAD><TITLE>Debug Textarea</TITLE><meta http-equiv='Content-Type' content='text/html; charset=gb2312'></HEAD><style>* { font-size: 12px}body { margin: 10px; padding: 0px}table.list{ cursor: default; border:1px solid #cccccc background-color: #cccccc; border-collapse: collapse; border-Color: #cccccc;}</style><script language="javascript">// Coded by windy_sk <windy_sk@126.com> 20040205
function reportError(msg,url,line) { var str = "You have found an error as below: \n\n"; str += "Err: " + msg + " on line: " + line; alert(str); return true;}
window.onerror = reportError;
document.onkeydown = function() { if(event.ctrlKey){ switch(event.keyCode) { case 82: //r runcode(); break; case 83: //s savecode(); break; case 71: //g goto(prompt('Please input the line number', '1')); break; case 65: //a document.execCommand("SelectAll"); break; case 67: //c document.execCommand("Copy"); break; case 88: //x document.execCommand("Cut"); break; case 86: //v document.execCommand("Paste"); break; case 90: //z document.execCommand("Undo"); break; case 89: //y document.execCommand("Redo"); break; default: break; } event.keyCode = 0; event.returnValue = false; } return;}
function show_ln(){ var txt_ln = document.getElementById('txt_ln'); var txt_main = document.getElementById('txt_main'); txt_ln.scrollTop = txt_main.scrollTop; while(txt_ln.scrollTop != txt_main.scrollTop) { txt_ln.value += (i++) + '\n'; txt_ln.scrollTop = txt_main.scrollTop; } return;}
function editTab(){ var code, sel, tmp, r; event.returnValue = false; sel =event.srcElement.document.selection.createRange(); r = event.srcElement.createTextRange();
switch (event.keyCode){