Question

我的问题是var total不会计算变量，而是将它们串联在一起，但是当我使用数字而不是getAttribute（'cost'）时，一切都很好... 有什么办法可以解决这个问题吗？

我有此代码

日期：

 <div class="row">
    <div class="col-lg-2">
        <lable  for="supervisor " style="font-size: 16px ; text-align: center" class="form-control rounded" >Supervisor </lable>
    </div>
    <div class="col-lg-2">  
        <select name="supervisor" id="userslist" style="font-size: 16px ; text-align: center" class="form-control rounded " onchange="calculateCost()">
            <option disabled selected >Please Select Supervisor</option>
                <option  cost="111" cost2="300">John Doe 1 </option>

        </select>
    </div>
    <div class="col-lg-2">
        <label for="superextra" style="font-size: 16px ; text-align: center" class="form-control rounded " >Extra Houres</label>
    </div>
    <div class="col-lg-2">
        <input type="number" name="superextra" id="super" min ="0" onchange="calculateCost()" value="0" style="font-size: 16px ; text-align: center" class="form-control rounded "> 
    </div>
    <div class="col-lg-2">
        <label for="supertotal" style="font-size: 16px ; text-align: center" class="form-control rounded ">Total Sum</label> 
    </div>
    <div class="col-lg-2">
        <input type="number" name="supertotal" id="totalsum" value=""  style="font-size: 16px ; text-align: center" class="form-control rounded ">
    </div>
</div>

和脚本

function calculateCost()
{

 //  check first that a user has been selected and also date has been picked

if(document.getElementById('userslist').value && document.getElementById("dateforgame").value)  
{ 

  //Supervisor
  let timeZone = new Date().toString().match(/([A-Z]+[\+-][0-9]+)/)[1];
  let chosenDate = new Date(document.getElementById("dateforgame").value + timeZone);
  var obj = document.getElementById('userslist');
  if (chosenDate.getDay() === 6) { 
    var userobj = document.getElementById('userslist');
var selectedUserCost2 = userobj.options[userobj.selectedIndex].getAttribute('cost2');  
   
    
    var extrah = document.getElementById('super').value;
     var extra = 240;
    var total = selectedUserCost2 + (extra * extrah);
    document.getElementById('totalsum').value = total;
    
  } else {
      var userobj = document.getElementById('userslist');
var selectedUserCost = userobj.options[userobj.selectedIndex].getAttribute('cost');
 
  
 var extrah = document.getElementById('super').value;
   var extra = 120;
    var total = selectedUserCost + (extra * extrah);
    document.getElementById('totalsum').value = total;
  }
}

}

Answer 1

getAttribute()方法的返回值类型为String，请参见API doc

您需要使用parseInt()方法将String类型转换为Number才能执行任何算术运算。

如何在函数内部计算变量

1 个答案: