function show_sub(v) { //alert(v); var param = ""; param += "PId=" + $("#PId").val(); param += "&type=" + $("#HidType").val(); param += "&select=" + v; var url = "PackageAddWayBills.aspx?" + param; //wwwwalert(url); window.location.href = url; }
<asp:DropDownList ID="DDLCountry" CssClass="DDLCountry" runat="server" onchange="show_sub(this.options[this.options.selectedIndex].value)">
<asp:ListItem Text="--请选择--" Value="0"></asp:ListItem>
</asp:DropDownList>
原文：https://www.cnblogs.com/JoeChou-sh/p/9393645.html