php - 使用javascript将下拉选择选项传递给url

Question

使用javascript将下拉选择选项传递给url，它工作正常，但问题是现在<option>Select</option>也传递给url，我怎么能 <option>Select</option>在将选择选项值传递给url时禁用？我只想将名称发送到网址，除了<option>Select</option>？

function getComboC(sel) { 
var name=document.getElementById("name");
var input_val = document.getElementById("name").value;
name.action = "searchexpense.php?name="+input_val+"";
name.submit();


<form name="name" id="name"><select class="select10" 
name="pname" id="name" style="width:150px;"  onChange="getComboC(this)">

<option value="0"><--Select--> </option>

<?php 
$query=mysql_query("SELECT pname from expenses order by id");
while($row=mysql_fetch_assoc($query))
{
$val2=$row['pname'];
?>
<option  value="<?=$val2;?>"  <? if ($_GET['pname']  == $val2)
{ echo "selected='selected'"; }?> >
<?=$row['pname'];?>

</option>

<?php }?>

</select></form>

URL While Select <option>Select</option>
searchexpense.php?pname=0

动态选项选择
searchexpense.php?pname=Test

Answer 1

你id对多个元素使用相同的，比如表单和选择。id 必须是唯一的，所以尝试：

<form name="my_frm" id="my_frm">
<select class="select10" name="pname" id="name" style="width:150px;"  onChange="getComboC(this)">
....

和js函数：

function getComboC(sel) { 
  //do not submit if default "select" is selected
  if( sel.value != "0" ) {
    var selected_value = sel.value; //selected dropdown value
    document.my_form.action = "searchexpense.php?name="+selected_value;
    document.my_form.submit();
  }
}