How to find the greatest value of elements in this kind of Array?

Question

I am looking for correct code so function named "finder()" can execute and find the highest value in Array named "sum" . When press "Find max" button result is :"[object HTMLInputElement] " Thank you for any help! Here is code:

<html>
  <head>
   <title>Max</title>
    <meta charset="utf-8">
    <script type="text/javascript">
      var sum = document.getElementsByName('addends');
      function add() {
          var x = document.getElementById('apendiks');
          x.innerHTML+="<br/><input type='text' name='addends' size='7'>";
        }

       function finder() {  
          var max = sum[0];           
           for(i=0; i<sum.length;i++){

                if(sum[i] > max){
                   max = sum[i];
                }                 
           } 

          document.getElementById('showMaxValue').innerHTML = max;
        }

        function gather() {

          var total=0;
          for(i=0; i < sum.length; i++){

              total+=parseFloat(sum[i].value);
          }
          document.getElementById('score').innerHTML = total;
        }
        </script>
  </head>
  <body>
   <p><input type="button" onclick="add()" value="Add a new box"> </p>
   <p><input type="button" onclick="" value="-"> </p>

  <div id="apendiks"></div>
   <p><input type="button" onclick="gather()" value="Total sum"> </p>
    <p>Score: <b id="score"></b></p>
   <p><input type="button" onclick="finder()" value="Find max"> </p>
   <p id="showMaxValue"></p>
  </body>
 </html>

what if I entered `398 49 fdr` into the text field `'addends'` ? — RomanPerekhrest, Apr 16 '16 at 13:16
Sum[] is an array of html input objects. I think you are trying to get the value out of the input, but instead you are comparing input elements to each other instead of the value they contain. — klog, Apr 16 '16 at 13:17
Multiple problems ... please see http://stackoverflow.com/questions/14028959/why-does-jquery-or-a-dom-method-such-as-getelementbyid-not-find-the-element — charlietfl, Apr 16 '16 at 13:19
@charlietfl but he got the result `When press "Find max" button result is :"[object HTMLInputElement] "` — gurvinder372, Apr 16 '16 at 13:20

gurvinder372 · Accepted Answer · 2016-04-16T13:33:51.850

0

var sum = document.getElementsByName('addends');

This line will give you a list of Nodes, not an Array.

In your finder method, you need to treat it as such

  function finder() 
  {
       var max = paeseInt(sum[0].value) ;
       for(i=0; i<sum.length;i++){
            if(parseInt(sum[i].value) > max && !isNaN(sum[i].value)){ //assuming that strings should be ignored
               max = parseInt(sum[i].value) ;
            }
       } 
       document.getElementById('showMaxValue').innerHTML = max;
  }

edited Apr 16 '16 at 13:33

answered Apr 16 '16 at 13:16

gurvinder372

66,980
10
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what if I entered `398-49fdr` into the text field `addends` ? – RomanPerekhrest Apr 16 '16 at 13:17
what should be the output in this case? – gurvinder372 Apr 16 '16 at 13:18
what output will give your solution with this input value `-f0j381` ? How do you think ... – RomanPerekhrest Apr 16 '16 at 13:20
Same here...comparing strings not numbers – charlietfl Apr 16 '16 at 13:21
@RomanPerekhrest But what is the intended output? Do you want to ignore the strings? – gurvinder372 Apr 16 '16 at 13:25
he said: "find the highest value". You should elaborate what exactly he(author) is expecting to get under that "highest value" with untidy input – RomanPerekhrest Apr 16 '16 at 13:30
1

`sum[i].value` is string regardless if user input is a number or not – charlietfl Apr 16 '16 at 13:31
Thank you gurvinder372 for correct answer! Thank you all who post answer here. – Car Lazar Apr 16 '16 at 14:02

score 0 · Answer 2 · answered Apr 16 '16 at 13:19

Use .value to get the value of input field

<html>
  <head>
   <title>Max</title>
    <meta charset="utf-8">
    <script type="text/javascript">
      var sum = document.getElementsByName('addends');
        function add() {

          var x = document.getElementById('apendiks');

          x.innerHTML+="<br/><input type='text' name='addends' size='7'>";

        }

        function finder() {

          var max = sum[0].value;

           for(i=0; i<sum.length;i++){



                if(sum[i].value > max){


                   max = sum[i].value;

                }

           } 

          document.getElementById('showMaxValue').innerHTML = max;
        }





        function gather() {



          var total=0;
          for(i=0; i < sum.length; i++){

              total+=parseFloat(sum[i].value);
          }
          document.getElementById('score').innerHTML = total;
        }

        </script>
  </head>

  <body>
   <p><input type="button" onclick="add()" value="Add a new box"> </p>
   <p><input type="button" onclick="" value="-"> </p>


  <div id="apendiks"></div>
   <p><input type="button" onclick="gather()" value="Total sum"> </p>
    <p>Score: <b id="score"></b></p>
   <p><input type="button" onclick="finder()" value="Find max"> </p>
   <p id="showMaxValue"></p>
  </body>
 </html>

How to find the greatest value of elements in this kind of Array?

2 Answers2