Doing a Post with unchecked checkboxes

If you have to do JSPs you will certainly run into the problem that you have to submit a Form where you can enable or diasble certain form elements. That´s ok for checkboxes, because if they are not checked, they are won´t get submitted. But what about input fields ? They will be submitted all the time, regardless of the checkbox. This will lead to difficulties processing the fields values in the portlet class, because you will have (for example) 2 values for the selected checkbixes and 6 values for all input fields.

The solution is to dynamically disable all input fields that should not be submitted.

You can do it by javascript like this:

function toggleDisable(identifier) {
  document.getElementById(identifier).disabled = 
(document.getElementById(identifier).disabled) ? false : true;

This function toggles the desired input field from disabled to enabled and back. And this is the checkbox doing the javascript call:

<input type="checkbox"onclick="toggleDisable('fieldId');" name="CBName" value="CBName" <%=selected %>>

The Input Field itself is very straightforward:

<input id="fieldId" name="field" <%=disabled %>  type="text" value="value" />

By doing this you can make sure, that you will always submit as much checkbox values as input field values.

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If you have any questions, feel free to leave a comment.