根據現場輸入計算總和

Question

如何求和多個文本輸入的值？

當前總和不正確，因爲它不斷記住和總結之前輸入字段中的先前值。

我有以下代碼：

HTML：

<div class="form-group"> 
    <legend>Risicopotentieel</legend> 
    <label for="email">Email address:</label> 
    <select class="selectpicker" id="selectpicker1"> 
    <option value="1">text1</option> 
    <option value="2">text2</option> 
    <option value="3">text3</option> 
    <option value="4">text4</option> 
    </select> 
    <label for="email">Email address:</label> 
    <select class="selectpicker" id="selectpicker2"> 
    <option value="1">text1</option> 
    <option value="2">text2</option> 
    <option value="3">text3</option> 
    <option value="4">text4</option> 
    </select> 
    <label for="email">Email address:</label> 
    <select class="selectpicker" id="selectpicker3"> 
    <option value="1">text1</option> 
    <option value="2">text2</option> 
    <option value="3">text3</option> 
    <option value="4">text4</option> 
    </select> 
</div> 

<div class="form-group"> 
    <legend>Score</legend> 
    <label for="email">&nbsp;&nbsp;</label> 
    <input type="text" class="form-control" id="scorefield1"> 
    <label for="email">&nbsp;&nbsp;</label> 
    <input type="text" class="form-control" id="scorefield2"> 
    <label for="email">&nbsp;&nbsp;</label> 
    <input type="text" class="form-control" id="scorefield3"> 
    <label for="email">Totaalscore</label> 
    <input type="text" class="form-control" name="riskpottotalscore" id="riskpottotalscore"> 
</div> 

jQuery代碼首先複製所選擇的選項的輸入字段的值。這工作正常。此後，我想計算總和，那是錯誤的。可變totalPoints保持記憶的成績，但我只是想對那些在得分字段1，2和3實際選擇的值來計算的總和：

scorefieldrisk: function(){ 
    totalPoints = 0; 
    for (var i = 1; i <= 7; i++) { 
     (function (i) { 
      $('select[id$="selectpicker' + i + '"]').on("change", function() { 
       document.getElementById('scorefield'+i).value = this.value; 
       if(!isNaN(this.value) && this.value.length!=0) { 
        totalPoints +=(parseInt(this.value)); 
        document.getElementById('riskpottotalscore').value = totalPoints; 
       } 
      }); 
     })(i); 
    } 
}, 

Answer 1

你應該從每次零重做總和。

您的代碼可以簡化爲只有一個函數作爲所有select元素的處理程序。您也可以使用統一的+運算符將字符串值轉換爲數字：

$('.selectpicker').on('change', function() { 
    totalPoints = 0; 
    $('.selectpicker').each(function() { 
     totalPoints += +this.value; 
    }); 
    $('#riskpottotalscore').val(totalPoints); 
});