Javascript or jQuery auto populate one input text based on another input value

Question

I am not good at JS or jQuery. I take the follow code for better explaining what I what. When a user input 400 or more to triglycerides, the LDL is autopopulated with 'N/A'. How do I implement JS or jQuery to do that? Thanks

<form>
 <input name='triglycerides" value="" />
 <input name='LDL' value="" />
</form>

My actual code is as follows:

$('#ldl_override').keyup(function(){
var val = parseInt($(this).val());
if(val > 399)
   $('#qIn726').val('N/A');
});


 elseif($ldl_override && $questionID == 728)
 {
  $question .= "<input $maxLengthString id=\"ldl_override\" name=\"field[" . $questionID . "]\" type=\"text\" value=\"" . htmlspecialchars($answer) . "\" />\n";
 }

Sascha Galley · Accepted Answer · 2012-01-31 16:47:34Z

1

with jquery:

<form>
 <input name="triglycerides" value="" onChange="javascript: if($('#triglycerides').val() > 400) $('#LDL').val('N/A'); />
 <input id="LDL" name='LDL' value="" />
</form>

answered Jan 31, 2012 at 16:47

Sascha Galley

16.2k5 gold badges39 silver badges52 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Anthony Grist Over a year ago

The use of an onchange attribute with jQuery code kind of makes me want to weep...

庆峰扈 Over a year ago

Hi, Sascha, I tried your method, but didn't get it work. Please see my updated question and see if you have any idea on this. thanks

Senad Meškin · Accepted Answer · 2012-01-31 16:48:49Z

1

You can do it easily with jQuery

$('input[name="triglycerides"]').keyup(function(){
    var val = parseInt($(this).val());
    if(val > 399)
       $('input[name="LDL"]').val('N/A');
});

answered Jan 31, 2012 at 16:48

Senad Meškin

13.8k4 gold badges39 silver badges55 bronze badges

3 Comments

庆峰扈 Over a year ago

Thanks for your answer. Do you need to add anything to the html form?

Senad Meškin Over a year ago

no, just make sure to use IDs for elements, its easier to get element by id than searching it by attributes example <input type="text" id="LDS" /> then your js would look like $('#LDS').val('N/A');

庆峰扈 Over a year ago

It doesn't work anyway. I don't know why. I modified my question and added some real code, please help me to take a look. thanks

falsarella · Accepted Answer · 2012-01-31 17:53:30Z

0

Use id to select with #! For example:

HTML:

<form>
 <input id="triglycerides" value="" />
 <input id="triglycerides-result" value="" disabled="disabled" />
</form>

JQuery:

$('#triglycerides').keyup(function(){
    var val = parseInt($(this).val());
    if (val > 399)
       $('#triglycerides-result').val('high');
    else
       $('#triglycerides-result').val('normal');
});

See JsFiddle

answered Jan 31, 2012 at 17:53

falsarella

12.5k10 gold badges75 silver badges119 bronze badges

Comments

Jon · Accepted Answer · 2012-01-31 17:53:30Z

0

$('input[name="triglycerides"]').change(function() {
   var val = parseInt($(this).val());
   if(val > 399) {
      $('#LDL').val('N/A')  
   }
});

answered Jan 31, 2012 at 17:53

Jon

2302 silver badges4 bronze badges

Collectives™ on Stack Overflow

Javascript or jQuery auto populate one input text based on another input value

4 Answers 4

2 Comments

3 Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

2 Comments

3 Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related