如何在javascript中自动求和多个输入框内循环

我想计算我的输入框内部循环,如果完成,请帮我解决这个问题


<?php

$jumlah_form = 3;

    for($i=1; $i<=$jumlah_form; $i++){

    ?>

    <input type="text" id="txt1"  onkeyup="sum1();" /></br>


    <?php

    }

    ?>

    <input type="text" id="txt2" value= "0" /></br>

   <script>

  function sum1() {

      var txtFirstNumberValue = document.getElementById('txt1').value;

      var txtSecondNumberValue = document.getElementById('txt2').value;

      var result = parseInt(txtFirstNumberValue) + parseInt(txtFirstNumberValue) ;

      if (!isNaN(result)) {

         document.getElementById('txt2').value = result;

      }

   }

  </script>

http://img2.mukewang.com/61ee00df0001718702350112.jpg

通过循环创建三个输入框,我想计算三个输入框,并在用户输入数字时将结果解析为结果框


海绵宝宝撒
浏览 237回答 2
2回答

天涯尽头无女友

我想您是在问如何编写 JavaScript 以便将所有输入框的总数加起来,无论 PHP 创建了多少?如果是这样,那么一个好方法是为所有文本框提供相同的类。然后,JavaScript 可以选择具有该类的所有框,遍历它们并获得总值。这是一个使用 3 个文本框的工作示例(就好像 PHP 以这种方式生成它们一样):var textboxes = document.querySelectorAll(".sum");textboxes.forEach(function(box) {&nbsp; box.addEventListener("keyup", sumAll);});function sumAll() {&nbsp; var total = 0;&nbsp; textboxes.forEach(function(box) {&nbsp; &nbsp; var val;&nbsp; &nbsp; if (box.value == "") val = 0;&nbsp; &nbsp; else val = parseInt(box.value);&nbsp; &nbsp; total += val;&nbsp; });&nbsp; document.getElementById("total").innerText = total;}<input type="number" id="txt1" class="sum" value="0" /><br/><input type="number" id="txt2" class="sum" value="0" /><br/><input type="number" id="txt3" class="sum" value="0" /><br/><br/><br/> Total: <span id="total"></span>

largeQ

用 php 生成 html:$count = 5;for($i=1;$i <= $count;$i++) {&nbsp; echo "<input type='number' id='"."txt".i."' /></br>"}从输入计算总和:<!DOCTYPE html><html><head>&nbsp; <meta charset="UTF-8">&nbsp; <title>Hello World</title></head><body>&nbsp; <form onsubmit="submitForm(this); return false;" >&nbsp; &nbsp; <input type="number" id='text1'>&nbsp; &nbsp; <input type="number" id='text2'>&nbsp; &nbsp; <input type="number" id='text3'>&nbsp; &nbsp; <input type="number" id='text4'>&nbsp; &nbsp; <input type="number" id='text5'>&nbsp; &nbsp; <button type="submit" >Calculate</button>&nbsp; </form>&nbsp; <div>&nbsp; &nbsp; <p>Result:</p>&nbsp; &nbsp; <p id='result'></p>&nbsp; </div>&nbsp;&nbsp;&nbsp; <script>&nbsp; &nbsp; function submitForm(form) {&nbsp; &nbsp; &nbsp; &nbsp; let toReturn = 0;&nbsp; &nbsp; &nbsp; &nbsp; const inputs = form.getElementsByTagName("input");&nbsp; &nbsp; &nbsp; for(let x = 0; x < inputs.length; x++ ) {&nbsp; &nbsp; &nbsp; &nbsp; toReturn += parseInt(inputs[x].value ? inputs[x].value : 0);&nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; &nbsp;&nbsp;&nbsp; &nbsp; &nbsp; document.getElementById('result').innerHTML = toReturn;&nbsp; &nbsp; &nbsp; return false;&nbsp; &nbsp; }&nbsp; </script></body></html>
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