Hallo,
ich habe aus einem Buch zum Thema OleDb Connection ein Programm ausprobiert. Es funktioniert alles soweit aber bei UPDATE kommt ein Syntaxfehler. Nun habe ich das ganze in mein Programm eingebaut und wieder das selbe. Was ich im Netz gefunden habe passt soweit alles mit dem überein was ich habe.
Hier das Fehlerprotokoll:
Hier der Code von dem Bsp. aus dem Buch:
Würde mich freuen wenn mir jemand sagen könnte an was es liegt. Eine Anwendung ohne Update ist etwas dumm
Vielen Dank
ich habe aus einem Buch zum Thema OleDb Connection ein Programm ausprobiert. Es funktioniert alles soweit aber bei UPDATE kommt ein Syntaxfehler. Nun habe ich das ganze in mein Programm eingebaut und wieder das selbe. Was ich im Netz gefunden habe passt soweit alles mit dem überein was ich habe.
Hier das Fehlerprotokoll:
Hier der Code von dem Bsp. aus dem Buch:
Code:
using System;
using System.Collections.Generic;
using System.Drawing;
using System.Windows.Forms;
using System.Data;
using System.Data.OleDb;
namespace MDB_DB_Test1
{
/// <summary>
/// Description of MainForm.
/// </summary>
public partial class MainForm : Form
{
private OleDbConnection conn;
private OleDbDataAdapter dataAdapter;
private DataTable dataTable;
private DataSet ds;
private int currRec = 0;
private int totalRec = 0;
private bool insertSelected;
[STAThread]
public static void Main(string[] args)
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new MainForm());
}
public MainForm()
{
//
// The InitializeComponent() call is required for
// Windows Forms designer support.
InitializeComponent();
//
// TODO: Add constructor code after the
// InitializeComponent() call.
}
private void BtnLoadTableClick(object sender, EventArgs e)
{
this.Cursor = Cursors.WaitCursor;
string connectionString = "provider=Microsoft.Jet.OLEDB.4.0;"+
"data source = C:\\programmersheaven.mdb";
conn = new OleDbConnection(connectionString);
string commandString = "SElECT * from article";
dataAdapter = new OleDbDataAdapter(commandString, conn);
InitializeCommands();
ds = new DataSet();
dataAdapter.Fill(ds, "article");
dataTable = ds.Tables["article"];
currRec = 0;
totalRec = dataTable.Rows.Count;
FillControls();
ToggleControls(true);
this.Cursor = Cursors.Default;
}
private void FillControls()
{
txtArticleID.Text = dataTable.Rows[currRec]["artID"].ToString();
txtArticleTitle.Text = dataTable.Rows[currRec]["title"].ToString();
txtArticleTopic.Text = dataTable.Rows[currRec]["topic"].ToString();
txtAuthorID.Text = dataTable.Rows[currRec]["authorID"].ToString();
txtAuthorName.Text = dataTable.Rows[currRec]["authorName"].ToString();
txtNumOfLines.Text = dataTable.Rows[currRec]["lines"].ToString();
txtDateOfPublishing.Text = dataTable.Rows[currRec]["dateOfPublishing"].ToString();
}
private void InitializeCommands()
{
//Preparing Select Command
dataAdapter.SelectCommand = conn.CreateCommand();
dataAdapter.SelectCommand.CommandText =
"SELECT * FROM article";
//Preparing Insert Command
dataAdapter.InsertCommand = conn.CreateCommand();
dataAdapter.InsertCommand.CommandText =
"INSERT INTO article(artID, title, topic, authorID, authorName, lines, dateOfPublishing)"+
"VALUES(@artID, @title, @topic, @authorID, @authorName, @lines, @dateOfPublishing)";
AddParams(dataAdapter.InsertCommand, "artID", "title", "topic", "authorID", "authorName", "lines", "dateOfPublishing");
//Preparing Update Command
dataAdapter.UpdateCommand = conn.CreateCommand();
dataAdapter.UpdateCommand.CommandText = "UPDATE article SET " +
"title = @title, " +
"topic = @topic, " +
"authorID = @authorID,"+
"authorName = @authorName,"+
"lines = @lines, " +
"dateOfPublishing = @dateOfPublishing,"+
"WHERE artID = @artID";
AddParams(dataAdapter.UpdateCommand, "title", "topic", "authorID", "authorName", "lines", "dateOfPublishing", "artID");
//Preparing Delete Command
dataAdapter.DeleteCommand = conn.CreateCommand();
dataAdapter.DeleteCommand.CommandText = "DELETE FROM article WHERE artID = @artID";
AddParams(dataAdapter.DeleteCommand, "artID");
}
private void AddParams(OleDbCommand commandString, params string[] cols)
{
//Adding Hectice parameters in OleDb Commands
foreach(string col in cols)
{
commandString.Parameters.Add("@" + col, OleDbType.Char, 0, col);
}
}
private void ToggleControls(bool val)
{
txtArticleTitle.ReadOnly = val;
txtArticleTopic.ReadOnly = val;
txtAuthorID.ReadOnly = val;
txtNumOfLines.ReadOnly = val;
txtDateOfPublishing.ReadOnly = val;
btnLoadTable.Enabled = val;
btnNext.Enabled = val;
btnPrevious.Enabled = val;
btnEditRecord.Enabled = val;
btnDeleteRecord.Enabled = val;
btnInsertRecord.Enabled = val;
btnSave.Enabled = !val;
btnCancel.Enabled = !val;
}
void BtnNextClick(object sender, EventArgs e)
{
currRec++;
if(currRec>=totalRec)
currRec=0;
FillControls();
}
void BtnPreviosClick(object sender, EventArgs e)
{
currRec--;
if(currRec<0)
currRec=totalRec-1;
FillControls();
}
void BtnEditRecordClick(object sender, EventArgs e)
{
ToggleControls(false);
}
void BtnSaveClick(object sender, EventArgs e)
{
lblLabel.Text = "Saving Changes...";
this.Cursor = Cursors.WaitCursor;
DataRow row = dataTable.Rows[currRec];
row.BeginEdit();
row["title"] = txtArticleTitle.Text;
row["topic"] = txtArticleTopic.Text;
row["authorID"] = txtAuthorID.Text;
row["authorName"] = txtAuthorName.Text;
row["lines"] = txtNumOfLines.Text;
row["dateOfPublishing"] = txtDateOfPublishing.Text;
row.EndEdit();
dataAdapter.Update(ds, "article");
ds.AcceptChanges();
ToggleControls(true);
insertSelected = false;
this.Cursor = Cursors.Default;
lblLabel.Text = "Changes Saved";
}
void BtnCancelClick(object sender, EventArgs e)
{
if(insertSelected)
{
BtnDeleteRecordClick(null, null);
insertSelected = false;
}
FillControls();
ToggleControls(true);
}
void BtnDeleteRecordClick(object sender, EventArgs e)
{
DialogResult res = MessageBox.Show(
"Are you sure you want to delet the current record?",
"Confirm Record Deletion", MessageBoxButtons.YesNo);
if(res == DialogResult.Yes)
{
DataRow row = dataTable.Rows[currRec];
row.Delete();
dataAdapter.Update(ds, "article");
ds.AcceptChanges();
lblLabel.Text = "Record Deleted";
totalRec--;
currRec = totalRec-1;
FillControls();
}
}
void BtnInsertRecordClick(object sender, EventArgs e)
{
insertSelected = true;
DataRow row = dataTable.NewRow();
dataTable.Rows.Add(row);
totalRec = dataTable.Rows.Count;
currRec = totalRec-1;
row["artID"] = totalRec;
txtArticleID.Text = totalRec.ToString();
txtArticleTitle.Text = "";
txtArticleTopic.Text = "";
txtAuthorID.Text = "";
txtAuthorName.Text = "";
txtNumOfLines.Text = "";
txtDateOfPublishing.Text = DateTime.Now.Date.ToString();
ToggleControls(false);
}
}Würde mich freuen wenn mir jemand sagen könnte an was es liegt. Eine Anwendung ohne Update ist etwas dumm
Vielen Dank
Zuletzt bearbeitet:
