size of td in table also changed

when i pressed the key it will effect the size of another td

<tr><td class="value">source </td><td class="text"> 


<input type="text" id="txt_sh_source" onKeyPress="src_record()" maxlength="3">
<input type="text" id="srcid" style="display:none;">
<div id="div_src" class="search_form" ></div>

and its css is }

div.search_form
{
position:fixed;
 background-color开发者_StackOverflow中文版:white;

}td.value
{
background-color:#00628B;
color:#E6E6DC;
height:50;

}

3 options I can suggest to you.

1. Give a maximum character length to your input type form to avoid the user to key in characters that will overlap your tds.

2. Set a fixed width of each of your td.

3. Use css instead of td. Tables are not of standard use today.