(C#)數據庫小工具實現代碼

在編寫有關數據庫方面的C#程序時，經常需要知道數據庫的表中各字段的以下信息：
　　1. 用於OracleParameter(或SqlParameter,...)中的字段和屬性的數據庫特定的數據類型。
　　2. 其對應的.NET數據類型。
　　如下面的程序片斷所示：

using (OracleConnection conn = new OracleConnection(Pub.ConnString))
{
conn.Open();
OracleCommand comm = new OracleCommand(
"SELECT trdate,txcode,drcrf,amount,balance,tellerno,txnote,zoneno,nodeno FROM detail "+
"WHERE accno=:accno AND currtype=:currtype ORDER BY accno,currtype,trdate,seqno", conn);
comm.Parameters.Add("accno", OracleDbType.Int64).Value = long.Parse(acc.Substring(4,13));
comm.Parameters.Add("currtype", OracleDbType.Int16).Value = curr;
using (OracleDataReader r = comm.ExecuteReader())
{
for (cnt = 0; r.Read(); cnt++)
{
DataRow dr = dt.NewRow();
dr["TrDate"] = r.GetDateTime(0);
dr["Txcode"] = r.GetInt32(1);
dr["Drcrf"] = IcbcEtc.GetDrcrfString(r.GetInt16(2));
dr["Amount"] = r.GetInt64(3) / R;
dr["Balance"] = r.GetInt64(4) / R;
dr["Tellerno"] = r.GetInt32(5);
dr["TxNote"] = r.GetString(6);
dr["Zoneno"] = r.GetInt32(7);
dr["Nodeno"] = r.GetInt32(8);
dr["Txname"] = DbTrxCode.GetNewName((int)dr["Txcode"]);
dt.Rows.Add(dr);
}
}
}

　　為此，我編寫了一個小工具，其應用示例如下：

　　這裡是源程序(ODP.NET版)，需要下載“Oracle Data Provider for .NET”，其命名空間是: Oracle.DataAccess.Client。

using System;
using System.Data;
using System.Text;
using System.Windows.Forms;
using System.Drawing;
using Oracle.DataAccess.Client;

namespace Skyiv.Util.Odpnet
{
class OdpnetDlg : Form
{
Label lblTable;
TextBox tbxConn;
TextBox tbxSql;
TextBox tbxMsg;
Button btnSubmit;
CheckBox chkStru;
DataGrid dgOut;
string strConn = "Data Source=ora-m38;User ID=test;Password=p@ssw0rd";

public OdpnetDlg()
{
SuspendLayout();

btnSubmit = new Button();
btnSubmit.Text = "執行";
btnSubmit.Location = new Point(10, 420);
btnSubmit.Size = new Size(60, 24);
btnSubmit.Click += new EventHandler(Submit_Click);
btnSubmit.Anchor = (AnchorStyles.Bottom | AnchorStyles.Left);

chkStru = new CheckBox();
chkStru.Text = "結構";
chkStru.Location = new Point(80, 420);
chkStru.Size = new Size(60, 24);
chkStru.Anchor = (AnchorStyles.Bottom | AnchorStyles.Left);

lblTable = new Label();
lblTable.Text = "數據源";
lblTable.Location = new Point(12, 460);
lblTable.Size = new Size(70, 24);
lblTable.Anchor = (AnchorStyles.Bottom | AnchorStyles.Left);

tbxConn = new TextBox();
tbxConn.Text = strConn;
tbxConn.Location = new Point(83, 456);
tbxConn.Size = new Size(626, 20);
tbxConn.Anchor = (AnchorStyles.Bottom | AnchorStyles.Left | AnchorStyles.Right);

tbxSql = new TextBox();
tbxSql.Text = "select *\r\nfrom v$version\r\n";
tbxSql.Location = new Point(10, 10);
tbxSql.Size = new Size(240, 200);
tbxSql.Multiline = true;
tbxSql.ScrollBars = ScrollBars.Both;
tbxSql.AcceptsReturn = true;
tbxSql.WordWrap = true;
tbxSql.Anchor = (AnchorStyles.Top | AnchorStyles.Left);

tbxMsg = new TextBox();
tbxMsg.Location = new Point(10, 220);
tbxMsg.Size = new Size(240, 190);
tbxMsg.Multiline = true;
tbxMsg.ScrollBars = ScrollBars.Both;
tbxMsg.AcceptsReturn = true;
tbxMsg.WordWrap = true;
tbxMsg.Anchor = (AnchorStyles.Top | AnchorStyles.Bottom | AnchorStyles.Left);

dgOut = new DataGrid();
dgOut.Location = new Point(260, 10);
dgOut.Size = new Size(450, 436);
dgOut.CaptionVisible = false;
dgOut.ReadOnly = true;
dgOut.Anchor = (AnchorStyles.Top | AnchorStyles.Bottom | AnchorStyles.Left | AnchorStyles.Right);

Controls.AddRange(new Control[]{btnSubmit, chkStru, lblTable, tbxSql, tbxMsg, tbxConn, dgOut});
Text = "數據庫查詢(ODPNET)";
ClientSize = new Size(720, 490);
WindowState = FormWindowState.Maximized;

ResumeLayout(false);
}

void DisplayError(Exception ex)
{
StringBuilder sb = new StringBuilder();
while (ex != null)
{
sb.Append("> ");
sb.Append(ex.GetType());
sb.Append(Environment.NewLine);