webmethodcachedata.asmx

东软内部材料（四）asp等相关的教学案例

<%@ WebService Language="c#" class="DataExample" %>

using System.Web.Services;
using System.Data;
using System.Data.SqlClient;

public class DataExample : WebService{

  [WebMethod(CacheDuration=30)]
  public DataSet GetDataSet(string City)
  {
    if(Application["ProductData" + City] == null)
      Application["ProductData" + City] = LoadDataSet(City);

    return (DataSet)Application["ProductData" + City];
  }

  private DataSet LoadDataSet(string City)
  {
    SqlConnection myConnection = new SqlConnection(ConfigurationSettings.AppSettings["DsnPubs"]);
    SqlDataAdapter myCommand = new SqlDataAdapter("select address, city from Authors where city ='" + City + "'", myConnection);

    DataSet products = new DataSet();
    myCommand.Fill(products, "products");

    return products;
  }
}