asmx ASp.net AJAX使用 ScriptManager

1创建asmx文件

取消

 // [System.Web.Script.Services.ScriptService]

　　的注释（创建能够被asp.net AJAX页面回调的web服务时，请务必删除注释符合）

2创建web方法

例：

[WebMethod]
public string HelloWorld()
{
return "Hello World";
}

　　下面是一个之前做的二级联动的文本框方法：

asmx中：

        //这个示例让Web方法能够访问Session对象
        [WebMethod(EnableSession = true)]
        public void DoSomeThing()
        {
            if (Session["myObject"] != null)
            { }
            else
            { }
        }

        [WebMethod]
        //从terr取出region
        public List<Region> GetRegionInTerritories(int RegionID)
        {
            List<Region> Region = new List<Region>();
            if (RegionID <0)
            {
                Region.Add(new Region(-1,"-请选择-"));
                return Region;
            }
            SqlConnection con = new SqlConnection(
                WebConfigurationManager.ConnectionStrings["conStr"].ConnectionString);
            SqlCommand cmd = new SqlCommand(
                "select * from Region where ID=@RegionID", con);
            cmd.Parameters.Add(new SqlParameter("@RegionID", SqlDbType.Int));
            cmd.Parameters["@RegionID"].Value = RegionID;
           // List<Region> Region = new List<Region>();
            try
            {
                con.Open();
                SqlDataReader reader = cmd.ExecuteReader();

                while (reader.Read())
                {
                    Region.Add(new Region(Convert.ToInt32(reader["ID"]),
                        reader["Name"].ToString()));
                }
                reader.Close();
            }
            catch (SqlException ex)
            {
                throw new ApplicationException("data error");
            }
            finally
            {
                con.Close();
            }
            return Region;
        }

aspx页面中：

<script type="text/javascript">
      
        function GetRegion(RegionID) {
            Territories.TerritoriesService.GetRegionInTerritories(RegionID, OnRequestComplete, OnError);
        }
        function OnRequestComplete(result) {
            var ddlRegion = $get("ddlRegion");
                //document.getElementById("ddlRegion");
            ddlRegion.innerHTML = "";
            
            for (var n = 0; n < result.length; n++) {
                var option = document.createElement("option");
                option.value = result[n].ID;
                option.innerHTML = result[n].Name;
                ddlRegion.appendChild(option);
            }
        }
        
     
        function OnError(result) {
            var lbl = $get("lblInfo");
            lbl.innerHTML = "<br>" + result.get_message() + "<br>";
        }
        
    </script>

aspx页面的ScriptManager:

  <asp:ScriptManager ID="ScriptManager1" runat="server">
        <Services>
            <asp:ServiceReference Path="/TerritoriesService.asmx" />
        </Services>
      </asp:ScriptManager>