Ajax简单示例之改变下拉框动态生成表格
1.建立一个aspx页面,html代码
<html xmlns="" >
<head runat="server">
<title>Untitled Page</title>
<script type="text/javascript">
var xmlHttp;
function createXMLHttpRequest()
{
if (window.ActiveXObject)
{
xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
}
else if (window.XMLHttpRequest)
{
xmlHttp = new XMLHttpRequest();
}
}
function startRequest()
{
//debugger;
var ProvinceID=document.getElementById("DropDownList1");
createXMLHttpRequest();
xmlHttp.onreadystatechange = handleStateChange;
xmlHttp.open("GET", "?ProvinceID="+ProvinceID.value, true);
xmlHttp.send(null);
}
function handleStateChange()
{
if(xmlHttp.readyState == 4) //0(未初始化);1(正在装载);2 (装载完毕);3 (交互中);4 (完成)
{
if(xmlHttp.status == 200) //200(OK);404(not found)
{
document.getElementById("gridiv").innerHTML=xmlHttp.responseText;
}
}
}
</script>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:DropDownList ID="DropDownList1" runat="server">
</asp:DropDownList>
</div>
<div id ="gridiv"></div>
</form>
</body>
</html>2.cs代码
using System.Data.SqlClient;
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
this.DropDownList1.Attributes.Add("onchange", "return startRequest();");
ListProvince();
if (ProvinceID != "")
{
GetCityByProvinceID(ProvinceID);
}
}
}
property#region property
private string ProvinceID