How to replace "undefined" with zero value in javascript or form to pass to spring-mvc controller?

Question

I am creating with a mouse event two float values in a javascipt jquery function and pass these values via form to a spring mvc controller as parameters. It works fine when the values get actually created but when I do not create them, the form passes a string "undefined" and the whole thing crashes.

my javascript values:

$('#width').val(event.pageX);
$('#height').val(event.pageY);

my form:

<form:form modelAttribute="Float2" method="POST" action="getFloats">
<input type="hidden" id="width" name="width" value=width>
<input type="hidden" id="height" name="height" value=height>
<button type="submit">Save the floats</button>

Is there a possibility to change the "undefined" to zero so that the form always passes floats?

score 1 · Accepted Answer · answered Aug 20 '20 at 20:42

Well, one option is to create html input tags already with the default values:

<input type="hidden" id="width" name="width" value="0">
<input type="hidden" id="height" name="height" value="0">

Then alter this values with JS if you need, otherwise default "0" values will be submitted

How to replace "undefined" with zero value in javascript or form to pass to spring-mvc controller?

1 Answers1