Calculadora

Codigo: <html><body> <table border="0" width="200" cellspacing="0" cellpadding="0" bgcolor="#FF7F00" style="border-color:black" onClick="previouskey=event.srcElement.innerText"> <tr> <td width="80%" bgcolor="#FFFFFF" id="result" style="font: 20px Arial;color:black;text-align='right'">0</td> </tr> <tr> <td width="100%" valign="middle" align="center"><table border="0" width="100%" cellspacing="0" cellpadding="0" style="font: 20px Arial;color:white"> <tr> <td width="80%" align="center"><table border="0" width="80%" cellspacing="0" cellpadding="0" style="cursor:hand;font: 20px Arial;color:white" onMouseover="if (event.srcElement.tagName=='TD')event.srcElement.style.color='yellow'" onMouseout="event.srcElement.style.color='white'" onselectStart="return false" onClick="calculate()" height="60"> <tr> <td width="20%" align="center" height="14">7</td> <td width="20%" align="center" height="14">8</td> <td width="20%" align="center" height="14">9</td> <td width="20%" align="center" height="14">/</td> </tr> <tr> <td width="20%" align="center" height="19">4</td> <td width="20%" align="center" height="19">5</td> <td width="20%" align="center" height="19">6</td> <td width="20%" align="center" height="19">*</td> </tr> <tr> <td width="20%" align="center" height="19">1</td> <td width="20%" align="center" height="19">2</td> <td width="20%" align="center" height="19">3</td> <td width="20%" align="center" height="19">-</td> </tr> <tr> <td width="20%" align="center" height="19">0</td> <td width="20%" align="center" height="19" onClick="pn();previouskey=1;event.cancelBubble=true">+/-</td> <td width="20%" align="center" height="19">.</td> <td width="20%" align="center" height="19">+</td> </tr> </table> </td> <td width="20%"><div align="left"><table border="0" width="80%" cellspacing="0" cellpadding="0"> <tr> <td width="100%" style="cursor:hand;font: 15px Arial;color:white;text-align:center" onClick="result.innerText=0;results=''">Limpar</td> </tr> </table> </div><div align="left"><table border="0" width="80%" cellspacing="0" cellpadding="0" height="81"> <tr> <td width="100%" style="cursor:hand;font:bold 32px Arial;color:white;text-align:center" onMouseover="event.srcElement.style.color='yellow'" onMouseout="event.srcElement.style.color='white'" onClick="calculateresult()">=</td> </tr> </table> </div></td> </tr> </table> </td> </tr></table> <script language="JavaScript1.2"> var results='' var previouskey='' var re=/(\/|\*|\+|-)/ var re2=/(\/|\*|\+|-){2}$/ var re3=/.+(\/|\*|\+|-).+/ var re4=/\d|\./ var re5=/^[^\/\*\+].+\d$/ var re6=/\./ function calculate(){ if (event.srcElement.tagName=="TD"){ if (event.srcElement.innerText.match(re4)&&previouskey=="=") results='' if (result.innerText.match(re3)&&event.srcElement.innerText.match(re)){ if (!results.match(re5)){ result.innerText="Error!" return } results=eval(results) if (results.toString().length>=12&&results.toString().match(re6)) results=results.toString().substring(0,12) result.innerText=results } results+=event.srcElement.innerText if (results.match(re2)) results=results.substring(0,results.length-2)+results.charAt(results.length-1) result.innerText=results } } function calculateresult(){ if (!results.match(re5)){ result.innerText="Error!" return } results=eval(results) if (results.toString().length>=12&&results.toString().match(re6)) results=results.toString().substring(0,12) result.innerText=results } function pn(){ if (result.innerText.charAt(0)!='-') result.innerText=results='-'+result.innerText else if (result.innerText.charAt(0)=='-') result.innerText=results=result.innerText*(-1) } </script> </body></html>