javascript - Get value of form text field with without submitting the form -

i have form on page , want able submit text box value (partnumber) query string in hyperlink without submitting form ? possible ? have done research , have tried document.getelementbyid("partnumber").value getting error "object required". code below.

 <form id="form3" name="form3" method="post" action="formpost?rmaid=<%=rmaid%>">     <input name="partnumber" type="text" id="partnumber" size="10" /> <a href="suggest.asp?partnumber=<%document.getelementbyid("partnumber").value%>"><span class="style11">suggest link</span></a> <input name="invoice" type="text" id="invoice" size="15" /> </form> 

i'll set new page open in pop window , list series of values in database need value selected come invoice field on original page. believe can done javascript new this, can ?

for looking pass values have found snippet works... put in child window

<script language="javascript">  function changeparent() {    window.opener.document.getelementbyid('invoice').value="value changed..";   window.close(); }  </script>   <form>  <input type=button onclick="javascript:changeparent()" value="change opener's textbox's value..">  </form>  

for input field should add onchange it. event should call function set link's value.

you can see example of here (it uses button press though , not input onchange event): http://www.java2s.com/code/javascript/html/changeurlandtextofahyperlink.htm

edit: added stack snippet illustrating solution.

function setsuggestlink() {      var suggest = document.getelementbyid('partnumber').value;      document.getelementbyid('innerspan').innerhtml =           "suggest link: suggest.asp?partnumber=" + suggest;      document.getelementbyid('querylink').href =           "suggest.asp?partnumber=" + suggest;  }

.style11 {    color:black;  }    .style2 {    text-decoration:none;  }

<form id="form3" name="form3" method="post" action="formpost?rmaid=somevalue">      <input name="partnumber" type="text" id="partnumber" size="10"              onchange="setsuggestlink()" /> </br>      <a id="querylink" class="style2" href="#">        <span id="innerspan" class="style11">suggest link</span>      </a></br>      <input name="invoice" type="text" id="invoice" size="15" />  </form>