新手问题 代码问题 希望大家帮忙

C# code

using System;using System.Data;using System.Web;using System.Collections;using System.Web.Services;using System.Web.Services.Protocols;using System.Data.SqlClient;/// <summary>/// WebService 的摘要说明/// </summary>[WebService(Namespace = "http://tempuri.org/")][WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]public class WebService : System.Web.Services.WebService {    public WebService () {        //如果使用设计的组件，请取消注释以下行         //InitializeComponent();     }    [WebMethod]    public string HelloWorld() {        return "Hello World";    }    public void ExcuteSql(string strSql)    {        SqlConnection conn = new SqlConnection();        conn.ConnectionString = "Server=localhost;" + "Database=Hospital;" + "Integrated Security=true;";        conn.Open();        SqlCommand cmd = new SqlCommand();        cmd.Connection = conn;        cmd.CommandText = strSql;        cmd.ExecuteNonQuery();        conn.Close();        conn.Dispose();    }    public DataTable ExcuteSelect(string strSql)    {        SqlConnection conn = new SqlConnection();        conn.ConnectionString = "Server=localhost;" + "Database=Hospital;" + "Integrated Security=true;";        conn.Open();        SqlCommand cmd = new SqlCommand();        cmd.Connection = conn;        cmd.CommandText = strSql;        SqlDataAdapter adapter = new SqlDataAdapter(strSql,conn);        DataSet ds = new DataSet();        adapter.Fill(ds, "table");        return ds.Tables["table"];    }    public bool HasName(string strSql)    {        SqlConnection conn = new SqlConnection();        conn.ConnectionString = "Server=localhost;" + "Database=Hospital;" + "Integrated Security=true;";        conn.Open();        SqlCommand cmd = new SqlCommand();        cmd.Connection = conn;        cmd.CommandText = strSql;        SqlDataReader reader = cmd.ExecuteReader();        return reader.Read();    }}

C# code

using System; 
 using System.Data; 
 using System.Configuration; 
 using System.Collections; 
 using System.Web; 
 using System.Web.Security; 
 using System.Web.UI; 
 using System.Web.UI.WebControls; 
 using System.Web.UI.WebControls.WebParts; 
 using System.Web.UI.HtmlControls; 
  
 public partial class EditInformation : System.Web.UI.Page 
 { 
     public string strSql; 
     WebService webS = new WebService(); 
     public DataTable dr; 
     protected void Page_Load(object sender, EventArgs e) 
     { 
         if (Session["UserLevel"] == null || Session["UserLevel"].ToString() != "User") 
         { 
             Response.Redirect("Error.aspx?"); 
         } 
         if (Page.IsPostBack) 
         { 
             strSql = "selecet * from Enterprises_Info where Ent='" + Session["UserID"].ToString() + "';"; 
             dr = webS.ExcuteSelect(strSql); 
             this.lbUser.Text=dr.Rows[0]["Ent_User"].ToString(); 
             this.tbPsw.Text = dr.Rows[0]["Ent_Psw"].ToString(); 
             this.tbName.Text = dr.Rows[0]["Ent_Name"].ToString(); 
             this.lbNO.Text=dr.Rows[0]["Ent_Code"].ToString(); 
             this.ddtype.SelectedValue = dr.Rows[0]["Ent_Economictype"].ToString();  
 
             this.ddInd.SelectedValue = dr.Rows[0]["Ent_Industry"].ToString(); 
             this.ddScale.SelectedValue = dr.Rows[0]["Ent_Scale"].ToString(); 
             this.tbDis.Text = dr.Rows[0]["Ent_District"].ToString(); 
             this.tbPosNO.Text = dr.Rows[0]["Ent_Postalcode"].ToString(); 
             this.tbMail.Text = dr.Rows[0]["Ent_Mail"].ToString(); 
             this.tbFor.Text = dr.Rows[0]["Ent_For"].ToString(); 
             this.tbPho.Text = dr.Rows[0]["Ent_Phonecode"].ToString(); 
             this.tbAdd.Text = dr.Rows[0]["Ent_Address"].ToString(); 
             this.tbRem.Text = dr.Rows[0]["Ent_Remarks"].ToString(); 
         } 
     } 
     protected void Button1_Click(object sender, EventArgs e) 
     { 
         if(Page.IsValid) 
         { 
             string strPsw=this.tbPsw.Text; 
             string strName=this.tbName.Text; 
             string strType=this.ddtype.SelectedValue; 
             string strInd=this.ddInd.SelectedValue; 
             string strScale=this.ddScale.SelectedValue; 
             string strDis=this.tbDis.Text; 
             string strPos=this.tbPosNO.Text; 
             string strMail=this.tbMail.Text; 
             string strFor=this.tbFor.Text; 
             string strPho=this.tbPho.Text; 
             string strAdd=this.tbAdd.Text; 
             string strRem=this.tbRem.Text; 
             strSql="update Enterprises_Info set Ent_Psw='"+tbPsw+"',Ent_Name='"+strName+"',Ent_Economictype='"+strType+"',Ent_Industry='"+strInd+"',Ent_Scale='"+strScale+"',Ent_District='"+strDis+"',Ent_Postalcode='"+strPos+"',Ent_Mail='"+strMail+"',Ent_For='"+strFor+"',Ent_Phonecode='"+strPho+"',Ent_Address='"+strAdd+"',Ent_Remarks='"+strRem+"',Ent_Lawstime='"+DateTime.Now+"' where Ent_ID='"+Session["UserID"].ToString()+"';"; 
             webS.ExcuteSql(strSql); 
             Response.Redirect(""); 
         } 
     } 
     protected void Button2_Click(object sender, EventArgs e) 
     { 
         Response.Redirect("EditInformation.aspx"); 
     } 
 } 
 

[解决办法]
public void ExcuteSql(string strSql)
{
==
[WebMethod]
public void ExcuteSql(string strSql)
{