javascriptで複利計算プログラム #JavaScript


 <script type="text/javascript">
      function Calculator() {
        var rate, amount, period;
        rate = parseInt(document.myform.rate.value, 10);
        amount = parseInt(document.myform.amount.value, 10);
        period = parseInt(document.myform.period.value, 10);
        document.myform.receipt.value = fukuri(rate, amount, period);
      }

      function fukuri(rate, amount, period) {
        var receipt;
        receipt = amount;

        var str = "";
        str += "<table class=’test’>";
        str += "<tr><th>預入期間</th><th>受取金額</th></tr>";

        //預入金額＝元金×(1＋金利)/100
        //Math.round：小数点以下を四捨五入
        for (var i = 1; i <= period; i++) {
          receipt = Math.round(receipt * (1 + rate / 100));
          str += "<tr><td>" + i + "年</td><td>" + receipt + "円</td></tr>";
        }

        str += "</table>";
        document.getElementById("result").innerHTML = str;
        return receipt;
      }

      function TableClear() {
        document.getElementById("result").innerHTML = "";
      }
    </script>

  <body>
    <h1>複利計算</h1>
    <p>金利・金額・預入期間(年)を入力してください。</p>
    <form name="myform">
      <table>
        <tr>
          <th>金利</th>
          <td><input type="text" name="rate" size="22" value="4" />％</td>
        </tr>
        <tr>
          <th>金額</th>
          <td><input type="text" name="amount" size="22" value="10000" />円</td>
        </tr>
        <tr>
          <th>預入期間</th>
          <td><input type="text" name="period" size="22" value="10" />年</td>
        </tr>
        <tr>
          <td colspan="2" class="btn">
            <input type="button" onclick="Calculator()" value="計算" />
            <input type="reset" onclick="TableClear()" value="クリア" />
          </td>
        </tr>
        <tr>
          <th>受取金額</th>
          <td><input type="text" name="receipt" size="22" />円</td>
        </tr>
      </table>
    </form>
    <hr />
    <div id="result"></div>
  </body>