中文XML论坛--帮忙啊，没办法了！xml与sql

想从sql从导出xml文件，使用VISUAL .NET2003编写的代码，不知道错在哪里了！代码测试无法通过，数据库已建立，并且在查询工具中可以正常查询。
请教各位高手哪个地方需要修改？
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using MSXML2;
using ADODB;

namespace example_8._1
{
/// <summary>
/// Form1 的摘要说明。
/// </summary>
public class Form1 : System.Windows.Forms.Form
{
  private System.Windows.Forms.TextBox textBox1;
  private System.Windows.Forms.Button button1;
  private System.Windows.Forms.Button button2;
  ADODB._Connection pConn;
        ADODB._Recordset pRS;
  String pSelStr;
  String pUser;
  String pPSW;
  String sname;
  String dbname;
  IXMLDOMDocument xmlDoc;
  /// <summary>
  /// 必需的设计器变量。
  /// </summary>
  private System.ComponentModel.Container components = null;

  public Form1()
  {
   //
   // Windows 窗体设计器支持所必需的
   //
   InitializeComponent();

   //
   // TODO: 在 InitializeComponent 调用后添加任何构造函数代码
   //
  }

  /// <summary>
  /// 清理所有正在使用的资源。
  /// </summary>
  protected override void Dispose( bool disposing )
  {
   if( disposing )
   {
    if (components != null)
    {
     components.Dispose();
    }
   }
   base.Dispose( disposing );
  }

  #region Windows 窗体设计器生成的代码
  /// <summary>
  /// 设计器支持所需的方法 - 不要使用代码编辑器修改
  /// 此方法的内容。
  /// </summary>
  private void InitializeComponent()
  {
   this.textBox1 = new System.Windows.Forms.TextBox();
   this.button1 = new System.Windows.Forms.Button();
   this.button2 = new System.Windows.Forms.Button();
   this.SuspendLayout();
   //
   // textBox1
   //
   this.textBox1.Location = new System.Drawing.Point(128, 48);
   this.textBox1.Multiline = true;
   this.textBox1.Name = "textBox1";
   this.textBox1.Size = new System.Drawing.Size(296, 208);
   this.textBox1.TabIndex = 0;
   this.textBox1.Text = "";
   //
   // button1
   //
   this.button1.Location = new System.Drawing.Point(152, 304);
   this.button1.Name = "button1";
   this.button1.Size = new System.Drawing.Size(72, 64);
   this.button1.TabIndex = 1;
   this.button1.Text = "从数据库表生成XML文档";
   this.button1.Click += new System.EventHandler(this.button1_Click);
   //
   // button2
   //
   this.button2.Location = new System.Drawing.Point(328, 304);
   this.button2.Name = "button2";
   this.button2.Size = new System.Drawing.Size(72, 64);
   this.button2.TabIndex = 2;
   this.button2.Text = "显示生成的XML文档";
   this.button2.Click += new System.EventHandler(this.button2_Click);
   //
   // Form1
   //
   this.AutoScaleBaseSize = new System.Drawing.Size(6, 14);
   this.ClientSize = new System.Drawing.Size(584, 445);
   this.Controls.Add(this.button2);
   this.Controls.Add(this.button1);
   this.Controls.Add(this.textBox1);
   this.Name = "Form1";
   this.Text = "从数据库表生成XML文档";
   this.ResumeLayout(false);

}
#endregion

  /// <summary>
  /// 应用程序的主入口点。
  /// </summary>
  [STAThread]
  static void Main()
  {
   Application.Run(new Form1());
  }

  private void button1_Click(object sender, System.EventArgs e)
  {

   if(this.Connect2DB())
   {
    xmlDoc=new DOMDocument40Class();
    IXMLDOMProcessingInstruction pPI;
    pPI=xmlDoc.createProcessingInstruction("xml","version='1.0' encoding='GB2312' standalone='no'");
    xmlDoc.appendChild(pPI as IXMLDOMNode);
    IXMLDOMComment pComment;
    pComment=xmlDoc.createComment("下面是实例");
    xmlDoc.appendChild(pComment as IXMLDOMNode);
    IXMLDOMElement pElement;
    IXMLDOMElement pElementChild;
    IXMLDOMText pText;
    pElement=xmlDoc.createElement("students");
    xmlDoc.appendChild(pElement as IXMLDOMNode);
                int count;
    pRS.MoveFirst();
    while(pRS.EOF==false)
    {
     count=0;
     pElement=xmlDoc.createElement("student");
     foreach(ADODB.Field pField in pRS.Fields)
     {
                        pElementChild=xmlDoc.createElement(pField.Name);
                        pText=xmlDoc.createTextNode(pRS.get_Collect(count).ToString());
      pElementChild.appendChild(pText as IXMLDOMNode);
      count++;
                        pElement.appendChild(pElementChild as IXMLDOMNode);
      //     MessageBox.Show(pField.Name);
     }
     xmlDoc.documentElement.appendChild(pElement as IXMLDOMNode);
     pRS.MoveNext();
    }
    xmlDoc.save(Application.StartupPath+"//"+"test.xml");
    MessageBox.Show("生成成功！");
    pRS.Close();
    pConn.Close();
   }

  }
  private bool Connect2DB()
  {
   try
   {
    pConn=new ConnectionClass();

    pRS=new ADODB.RecordsetClass();

    dbname="students";
    sname="aubs123"+"\\"+"JT";
    pUser="sa";
    pPSW="sa";
    pSelStr="SELECT * From students";

    pConn.Open("Provider=SQLOLEDB.1;Server=" + sname + ";Initial Catalog=" + dbname,pUser,pPSW,-1);
    pRS.Open(pSelStr,pConn,ADODB.CursorTypeEnum.adOpenDynamic,ADODB.LockTypeEnum.adLockOptimistic,-1);
    return true;
   }
   catch
   {
    return false;
   }
  }

  private void button2_Click(object sender, System.EventArgs e)
  {
   this.textBox1.Text=xmlDoc.xml;
  }
}
}


	W 3 C h i n a ( since 2003 ) 旗下站点苏ICP备05006046号《全国人大常委会关于维护互联网安全的决定》《计算机信息网络国际联网安全保护管理办法》	62.500ms