Usage of DataView in my custom DataBase Class

I make one database class, in which there is a dataView method. In the aspx file, this method was invoked with the purpose to display the data in database. But here the aspx file failed to display the data, not even the error message in the catch block.

Can anybody tell me why

cs file:

using System;
using System.Data;
using System.Data.SqlClient;

namespace database
{
public class DBClass
{

private SqlConnection conn;
private SqlCommand comm;
public DataSet ds;
public SqlDataAdapter dad;
public DataView dv;
private string sql;
private string connStr;
private string errInfo;

public void database()
{
errInfo = "";
}

public string ErrInfo
{
get {return errInfo;}
}
public string Sql
{
get {return sql;}
set {sql=value;}
}
public string ConnStr
{
get {return connStr;}
set {connStr=value;}
}

private void connDb()
{
conn = new SqlConnection(connStr);
try
{
conn.Open();
}
catch(SqlException e)
{
for(int i=0;i<e.Errors.Count;i++)
{
errInfo+="Error Sequential Number:" +i+ "\n" + "Error Info:" +e.Errors.Message+ "\n" + "Error Source:" +e.Errors.Source+ "\n" + "Program:" +e.Errors.Procedure;
}
conn.Close();
}

}

public void dataView()
{
connDb();
dad = new SqlDataAdapter(sql,conn);
ds = new DataSet();
dad.Fill(ds,"table");
DataView dv = new DataView(ds.Tables["table"]);
}

public void clear()
{
conn.Close();

}

}

}

aspx file:

<%@ Page Language="C#" Debug="true"%>
<%@ Register TagPrefix="database" Namespace="database" Assembly="database"%>

<script language="C#" runat="server">
void Page_Load(Object sender, EventArgs e)
{
DBClass db = new DBClass();
try
{
db.ConnStr = "server=localhost;database=article;uid=sa;pwd=''";
db.Sql = "select * from article";
db.dataView();
dg.DataSource = db.dv;
dg.DataBind();
db.clear();
}
catch
{
Response.Write(db.ErrInfo);
}
}
</script>
<ASP:DataGrid id="dg" runat="server"/>