根据 ${selectedcount} 显示不同的输出

Question

我希望预测公式 显示为：如果 ${selectedcount} > 30显示为${selectedcount} / 3 + 5如果 ${selectedcount} < 30显示为${selectedcount} / 3 - 5P/S：不是计算，只是公式<div id="demo" align="center"></div><script src="//code.jquery.com/jquery-1.12.0.min.js"></script><script type="text/javascript">  var selectedcount = '';function myFunction() {    document.getElementById("demo").innerHTML = `<table class="table table-striped table-dark" style="width:600px; float: right; margin-right: 330px;">     <tr>         <td style="text-align: center; color: #000000; text-align: left;">Current total number of students:</td>         <td style="text-align: center; font-weight: bold; color: #000000; text-align: left;">${selectedcount} students</td>     </tr><tr>    <td style="text-align: center; color: #000000; text-align: left;">Prediction Formula:</td>    <td style="text-align: center; color: #0000A0; text-align: left;">Number of students > 30 <br> <b>Average = number of students / 3 + 5</b></td>  </tr>  <tr>    <td></td>    <td style="text-align: center; color: #0000A0; text-align: left;">Number of students < 30 <br> <b>Average = number of students / 3 - 5</b></td>  </tr></table>`  }$(document).ready(function(){    $("#prg").change( function(){      selectedcount = $('#prg option:selected').data('prgcount');      if(selectedcount > 30){        average = selectedcount / 3 + 5;      } else{        average = selectedcount / 3 - 5;      }    });  });</script>目前，预测公式行未从当前学生总数中捕获 ${selectedcount}，如下所示：屏幕截图我已经删除了一些不相关的代码，希望对您有所帮助。请协助解决上述问题。谢谢你。

Answer 1

根据您的条件在渲染之前存储符号和分母。

像这样的东西。

function myFunction() {

   var predicDenom = parseInt(selectedcount) > 30 ? '3+5 : '3-5'; //Store the denominator based on number of students

   var predicSign = parseInt(selectedcount) > 30 ? '>' : '<'; // Also store the sign

    document.getElementById("demo").innerHTML = `

<table class="table table-striped table-dark" style="width:600px; float: right; margin-right: 330px;">

     <tr>

         <td style="text-align: center; color: #000000; text-align: left;">Current total number of students:</td>

         <td style="text-align: center; font-weight: bold; color: #000000; text-align: left;">${selectedcount} students</td>

     </tr>

<tr>

    <td style="text-align: center; color: #000000; text-align: left;">Prediction Formula:</td>

    <td style="text-align: center; color: #0000A0; text-align: left;">Number of students ${predicSign} 30 <br> <b>Average = number of students / ${predicDenom}</b></td>

  </tr>

</table>`

  }