button变灰的问题

Question

<input type="button" name="A" disabled value="A">
<input type="button" name="B" value="B" onclick="A.disabled=false">

Answer 1

document.formName.buttonName.disable=false;

Answer 2

<form name=form1>
  <input type=button name=a value="A" onclick="a()">
  <input type=button name=b value="B" disabled >
</form>
<script language=JavaScript>
  function a(){
    document.form1.b.disabled=false;  
  }
</script>

Answer 3

提交后按钮失效时间设定
*/
function buttonHalt(){
   window.setTimeout("halt()",50);
   window.setTimeout("reset()",5000);
}
function halt(){
   document.form1.print.disabled=true;
   document.form1.search.disabled=true;
   document.form1.research.disabled=true;
   document.all.div1.style.visibility='visible';
}
function reset(){
   document.form1.print.disabled=false;
   document.form1.search.disabled=false;
   document.form1.research.disabled=false;
   document.all.div1.style.visibility='hidden';
}