Ajax中通过JS代码自动获取表单元素值的示例代码

function getFormQueryString(frmID) //frmID是表单的ID号，请在表单form中先命名一个ID号
{
var frmID=document.getElementById(frmID);
var i,queryString = "", and = "";
var item;
var itemValue;
for( i=0;i<frmID.length;i++ )
{
item = frmID[i];
if ( item.name!=&#39;&#39; )
{
if ( item.type == &#39;select-one&#39; )
{
itemValue = item.options[item.selectedIndex].value;
}
else if ( item.type==&#39;checkbox&#39; || item.type==&#39;radio&#39;)
{
if ( item.checked == false )
{
continue; 
}
itemValue = item.value;
}
else if ( item.type == &#39;button&#39; || item.type == &#39;submit&#39; || item.type == &#39;reset&#39; || item.type == &#39;image&#39;)
{
continue;
}
else
{
itemValue = item.value;
}
itemValue = escape(itemValue);
queryString += and + item.name + &#39;=&#39; + itemValue;
and="&";
}
}
return queryString;
}