title: Allow only one checkbox selected. 1 checkbox each in two independent forms, all on one page
body: <p>I have a HTTP interface page that requires the user to upload various independent files.  For this I have created multiple tables that each have its own form.  </p>
  
  <p>In two of the tables I need one checkbox each that allows the user to select it which then requires that the file is installed on system startup. </p>
  
  <p>Both tables are for uploading system firmware, one table for primary firmware, and the other for backup firmware.  </p>
  
  <p>The system will crash if both firmwares are being uploaded, hence separate forms.  </p>
  
  <p>Because of this crashing issue, for the two checkboxes it needs to be: One selected, or the other selected, or neither selected.</p>
  
  <p>Here is a sample html code:</p>
  
  <pre><code>&lt;body&gt;
  
  &lt;div id="container"&gt; 
   &lt;table width="1000" border="0" cellpadding="1" class="uploadBox"&gt;
     &lt;tr&gt;
       &lt;td width="460" rowspan="2"&gt;
        &lt;form action="fileupload.html" method="post" enctype="multipart/form-data"&gt;
         &lt;b&gt;Update Primary System Firmware&lt;/b&gt;
          &lt;p style="margin-bottom: 2px"&gt; &lt;b&gt;File: &lt;/b&gt;
            &lt;input type="file" name="firmwaremain" size="30" /&gt;
            &lt;input type="submit" value="Upload" /&gt;
          &lt;/p&gt;
  
  
      &lt;/td&gt;
      &lt;td width="210" height="23"&gt;Current File Name:&lt;/td&gt;
      &lt;td width="117"&gt;Current File Size:&lt;/td&gt;
      &lt;td width="102"&gt;File Upload Date:&lt;/td&gt;
      &lt;td width="93"&gt;Install on Start&lt;/td&gt;
     &lt;/tr&gt;
     &lt;tr&gt;
      &lt;td&gt;~curFirmName~&lt;/td&gt;
      &lt;td width="117"&gt;~curFirmSize~&lt;/td&gt;
      &lt;td width="102"&gt;~curFirmDate~&lt;/td&gt;
      &lt;td width="93"&gt;&lt;input type="checkbox" name="firmPrim" id="firmPrim" /&gt;&lt;/td&gt;
     &lt;/tr&gt;
   &lt;/table&gt;
   &lt;/form&gt;
  
   &lt;table width="1000" border="0" cellpadding="1"&gt;
     &lt;tr&gt;
      &lt;td width="460" rowspan="2"&gt;
       &lt;form action="fileupload.html" method="post" enctype="multipart/form-data"&gt;
        &lt;b&gt;Update Backup System Firmware&lt;/b&gt;
          &lt;p style="margin-bottom: 2px"&gt;&lt;b&gt;File: &lt;/b&gt;
            &lt;input type="file" name="firmwarebackup" size="30" /&gt; 
            &lt;input type="submit" value="Upload" /&gt;
          &lt;/p&gt;
  
     &lt;/td&gt;
     &lt;td width="210" height="23"&gt;Current File Name:&lt;/td&gt;
     &lt;td width="117"&gt;Current File Size:&lt;/td&gt;
     &lt;td width="102"&gt;File Upload Date:&lt;/td&gt;
     &lt;td width="93"&gt;Install on Start&lt;/td&gt;
    &lt;/tr&gt;
    &lt;tr&gt;
     &lt;td&gt;~curBackName~&lt;/td&gt;
     &lt;td width="117"&gt;~curBackSize~&lt;/td&gt;
     &lt;td width="102"&gt;~curBackDate~&lt;/td&gt;
     &lt;td width="93"&gt;&lt;input type="checkbox" name="firmBackup" id="firmBackup" /&gt;&lt;/td&gt;
   &lt;/table&gt;
   &lt;/form&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p></p>
  
  <p>As you can see, they checkboxes are in two independent forms, so it has been difficult for me to run a JavaScript code, since (I think) it calls for the checkboxes to be in one form. </p>
  
  <p>Also I cant use radio buttons because they are in different forms, plus there has to be an option for neither to be selected.</p>
  
  <p>Is there a way to validate the whole page and check all forms so that only one check box can be selected on the page? </p>
  
  <p>Thanks!</p>
  
  <p>Regards, 
  Josh</p>