如果所有三个文本框<>然后是100％，则Javascript会验证错误的文本框

Question

我有一个包含4个文本框的表单，我需要验证方面的帮助。

我需要总的合并值为= 100％，如果小于或大于则显示错误。

例如

框1用户输入50％，框2用户输入30％，框3用户输入19％。 方框4将保留方框1,2和3的总值，即总计99％。当用户单击“提交”时，它应该验证并返回错误，例如，总计不等于100％。如果方框4的总和大于100％

目前，我有计算框4的总价值，但不确定如何进行验证！

    <SCRIPT language="JavaScript">

function CalculateCardT()
{
    formSectionA.CardTotal.value = 

parseFloat(formSectionA.strPercDeferredGoods.value) + parseFloat(formSectionA.strPercDeposits.value) + parseFloat(formSectionA.strPercSubscriptions.value);


    }
    </SCRIPT>


          <tr>
        <td rowspan="2" nowrap="nowrap"> % of CARD turnover</td>
        <td nowrap="nowrap">% Deferred delivery of goods</td>
        <td nowrap="nowrap">% Deposit is taken</td>
        <td nowrap="nowrap">% Subscriptions</td>
        <td nowrap="nowrap">% Total</td>
      </tr>
      <tr>
        <td nowrap="nowrap">
          <input name="strPercDeferredGoods" type="text" required="required" id="strPercDeferredGoods" tabindex="6" onBlur="CalculateCardT();"  onChange="CalculateCardT();" size="3" maxlength="3" /></td>
        <td nowrap="nowrap">
          <input name="strPercDeposits" type="text" required="required" id="strPercDeposits" " tabindex="7" onBlur="CalculateCardT();" onChange="CalculateCardT();" size="3" maxlength="3" />
         </td>
        <td nowrap="nowrap">
          <input name="strPercSubscriptions" type="text" required="required" id="strPercSubscriptions" tabindex="8"  onblur="CalculateCardT();" onChange="CalculateCardT();" size="3" maxlength="3"/></td>
        <td nowrap="nowrap">
          <input name="CardTotal" type="text" id="CardTotal" style="background-color:#CCC" size="3" maxlength="3" onKeyDown="return false;"/></td>
      </tr>

BTW。 我是菜鸟，正在使用Dreamweaver，因此请轻松编写代码！

Answer 1

首先-您使用的代码已过时，并且存在语法错误。

这是语法正确的HTML的较短版本

<table>
    <thead>
        <tr>
            <th>% Deferred delivery of goods</th>
            <th>% Deposit is taken</th>
            <th>% Subscriptions</th>
            <th>% Total</th>
        </tr>
    </thead>
    <tbody>
        <tr>
            <td>
                <input type="text" id="strPercDeferredGoods" />
            </td>
            <td>
                <input type="text" id="strPercDeposits" />
            </td>
            <td>
                <input type="text" id="strPercSubscriptions" />
            </td>
            <td>
                <input type="text" id="CardTotal" disabled="disabled" />
            </td>
        </tr>
    </tbody>
</table>

还有JavaScript，我在每一行都评论了它的功能，因此您可以从中学习：

// IIFE - create local "document"
(function (document) {

    // Store all of the "input" elements in the variable "elems"
    var elems = document.getElementsByTagName("input");

    // Store an array of id's of the items to sum in the variable "idsToSum"
    var idsToSum = ["strPercDeferredGoods", "strPercDeposits", "strPercSubscriptions"]

    // Loop through the "input" elements
    for (var i = 0; i < elems.length; i++) {

        // For each "input" element, add a "change" event listener
        // When the event happens, run the function
        elems[i].addEventListener("change", function () {

            // Define a variable "sum" and assign a value of 0 to it
            var sum = 0;

            // Loop through all of the "idsToSum"
            for (var a = 0; a < idsToSum.length; a++) {

                // If the value of the current input is a number (removing the % sign if applicable), then add the value to the "sum" variable.  Otherwise, add 0
                sum += isNaN(parseFloat(document.getElementById(idsToSum[a]).value.replace("%", ""))) ? 0 : parseFloat(document.getElementById(idsToSum[a]).value.replace("%", ""));
            }

            // If the value of "sum" is greater than 100
            if (sum > 100) {

                // Clear the "CardTotal" value
                document.getElementById("CardTotal").value = "";

                // Alert an error
                alert("Total is not equal to 100%");
            }

            // Otherwise
            else {

                // Assign the value of "CardTotal" to the value of "sum" and add a % sign
                document.getElementById("CardTotal").value = sum + "%";
            }
        });
    }

// IIFE - pass in global "document"
})(document);

注意：您的JavaScript应该放置在HTML结束符</body>

这是一个工作示例：

 (function (document) { var elems = document.getElementsByTagName("input"); var idsToSum = ["strPercDeferredGoods", "strPercDeposits", "strPercSubscriptions"] for (var i = 0; i < elems.length; i++) { elems[i].addEventListener("change", function () { var sum = 0; for (var a = 0; a < idsToSum.length; a++) { sum += isNaN(parseFloat(document.getElementById(idsToSum[a]).value.replace("%", ""))) ? 0 : parseFloat(document.getElementById(idsToSum[a]).value.replace("%", "")); } if (sum > 100) { document.getElementById("CardTotal").value = ""; alert("Total is not equal to 100%"); } else { document.getElementById("CardTotal").value = sum + "%"; } }); } })(document); 

 input{width:96%;} table,th,td{border:1px solid black; border-collapse:collapse;} 

 <table> <thead> <tr> <th>% Deferred delivery of goods</th> <th>% Deposit is taken</th> <th>% Subscriptions</th> <th>% Total</th> </tr> </thead> <tbody> <tr> <td> <input type="text" id="strPercDeferredGoods" /> </td> <td> <input type="text" id="strPercDeposits" /> </td> <td> <input type="text" id="strPercSubscriptions" /> </td> <td> <input type="text" id="CardTotal" disabled="disabled" /> </td> </tr> </tbody> </table> 

另外-您确实没有理由使用Dreamweaver。 花时间学习代码。 它确实非常简单，并且有大量的免费资源和HTML和JavaScript教程。