Update 出现异常~


<%@ Import Namespace="System.Data.SqlClient" %>
<%@ Import Namespace="System.Data"%>
<%@ Import Namespace="System"%>
<%@ Page Language="C#" ContentType="text/html"ResponseEncoding="gb2312" Debug="true"%>
<script Language="C#" runat="server">void Page_Load(Object Sender,EventArgs e){
{string strConn="Persist Security Info=false;";
strConn +="user id=sa;password=rabbit8818;database=guestbook;";
string queryStr="Select * From guest";
SqlConnection nwConn=new SqlConnection(strConn);
test.Text="ok!";
try{
nwConn.Open();
DataSet guestSet=new DataSet();
SqlDataAdapter guestAdapter=new SqlDataAdapter(queryStr,nwConn);
guestAdapter.Fill(guestSet,"guest");
DataRow guestRow=guestSet.Tables["guest"].NewRow();
guestRow["nickname"]="dd";
//guestRow["data"]=DateTime.Now;
guestRow["context"]="aa";
//guestRow["faceurl"]=faceselect.Value;
guestSet.Tables["guest"].Rows.Add(guestRow);
SqlCommandBuilder guestBuilder=new SqlCommandBuilder(guestAdapter);
guestAdapter.InsertCommand=guestBuilder.GetInsertCommand();
guestAdapter.Update(guestSet,"guest");
//guestSet.Clear();
//guestAdapter.Fill(guestSet,"guest");
//nwConn.Close();
}
catch(Exception exc)
{ 
Console.WriteLine(exc.ToString());
  test.Text="wrong!";
  }}}
</script><html>
<body>
<h4>连接测试例子
<form runat=server>
 <asp:label ID=test runat=server/>
</form></body>
</html>