看看EnableSession是WebMethod属性的一部分

Have a look at EnableSession as part of the WebMethod attribute

// C#
public class Service1 : System.Web.Services.WebService
{
    [System.Web.Services.WebMethod(EnableSession=true)]
    public double ConvertTemperature(double dFahrenheit)
    {
       Session["Conversions"] = (int) Session["Conversions"] + 1;
       double temperature = ((dFahrenheit - 32) * 5) / 9;

       Session.Abandon();
       return temperature;
    }
}