name相同获取值

<html>
<head>
</head>
<body>
<form name="form1" method="post" action="" >
<p>
<input type="text" name="plan_bm_num[]"  id="plan_bm_num[]" value="">,
<input type="text" name="plan_bm_num[]"  id="plan_bm_num[]"  value="">,
<input type="text" name="plan_bm_num[]"  id="plan_bm_num[]" value="">,
<input type="text" name="plan_bm_num[]"  id="plan_bm_num[]" value="">
</p>
  <p>
    <label for="plan_total_renshu"></label>
    <input type="text" name="plan_total_renshu" id="plan_total_renshu">
  </p>
  <p>
    <input type="button" name="button" id="button" value="按钮" onClick="check();">
  </p>
</form>
</body>
</html>
<script language="javascript">
function check(){
    var bm_num=;
    var names =document.getElementsByName("plan_bm_num[]");
    for(i=;i<names.length;i++){
    value=names[i].value;
    console.log(value);
    }
}
</script>