java script 指令碼的簡易計算器
阿新 • • 發佈：2018-11-01
<head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>簡易計算器</title> </head> <body> <table border="0" > <tr> <td colspan="3"><h3>簡易計算器</h3></td> </tr> <tr> <td>第一個數</td> <td colspan="3"><input name="txtNum1" type="text" id="txt1" size="25"/></td> </tr> <tr> <td>第二個數</td> <td colspan="3"><input name="txtNum2" type="text" id="txt2" size="25"/></td> </tr> <tr> <td><input name="addButton2" type="button" id="jia" value=" ＋ " onclick="jisuan('+')" /></td> <td><input name="subButton2" type="button" id="jian" value=" － " onclick="jisuan('-')" /></td> <td><input name="mulButton2" type="button" id="cheng" value=" × " onclick="jisuan('*')" /></td> <td><input name="divButton2" type="button" id="chu" value=" ÷ " onclick="jisuan('/')"/></td> </tr> <tr> <td>計算結果</td> <td colspan="3"><input name="txtresult" type="text" id="txt3" size="25" /></td> </tr> </table> <script type="text/javascript"> function jisuan(x) { var a=Number(document.getElementById("txt1").value); var b=Number(document.getElementById("txt2").value); var c; switch(x) { case "+": c=a+b;break; case "-": c=a-b;break; case "*": c=a*b;break; case "/":if(b!=0) c=a/b; else c="除數不能為0，請重新輸入"; break; } document.getElementById("txt3").value=c; } </script> </body>