using
System;
using
System.Collections.Generic;
using
System.ComponentModel;
using
System.Data;
using
System.Drawing;
using
System.Text;
using
System.Windows.Forms;
using
System.Data.OleDb;
namespace
tel_book
{
public
partial
class
Form1 : Form
{
public
Form1()
{
InitializeComponent();
}
private
void
button1_Click(
object
sender, EventArgs e)
{
if
(ValidateInputs() ==
false
)
return
;
string
connectionString =
"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=..\\..\\Employee.mdb"
;
OleDbConnection myConnection =
new
OleDbConnection(connectionString);
myConnection.Open();
int
employeeNumber =
int
.Parse(txtEmployeeNumber.Text);
string
name = txtName.Text;
string
address = txtAddress.Text;
string
query =
"insert into EMPLOYEE_TABLE (EmployeeNumber, Name, Address) VALUES ("
+ employeeNumber +
", '"
+ name +
"', '"
+ address +
"')"
;
OleDbCommand myCommand =
new
OleDbCommand();
myCommand.CommandText = query;
myCommand.Connection = myConnection;
myCommand.ExecuteNonQuery();
myConnection.Close();
MessageBox.Show(
"Created."
);
}
private
void
button2_Click(
object
sender, EventArgs e)
{
if
(ValidateInputs() ==
false
)
return
;
string
connectionString =
"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=..\\..\\Employee.mdb"
;
OleDbConnection myConnection =
new
OleDbConnection(connectionString);
myConnection.Open();
int
employeeNumber =
int
.Parse(txtEmployeeNumber.Text);
string
query =
"delete from EMPLOYEE_TABLE where EmployeeNumber = "
+ employeeNumber;
OleDbCommand myCommand =
new
OleDbCommand();
myCommand.CommandText = query;
myCommand.Connection = myConnection;
myCommand.ExecuteNonQuery();
myConnection.Close();
MessageBox.Show(
"Deleted."
);
}
private
void
button3_Click(
object
sender, EventArgs e)
{
if
(ValidateInputs() ==
false
)
return
;
string
connectionString =
"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=..\\..\\Employee.mdb"
;
OleDbConnection myConnection =
new
OleDbConnection(connectionString);
myConnection.Open();
int
employeeNumber =
int
.Parse(txtEmployeeNumber.Text);
string
name = txtName.Text;
string
address = txtAddress.Text;
string
query =
"update EMPLOYEE_TABLE set Name = '"
+ name +
"', Address = '"
+ address +
"' where EmployeeNumber = "
+ employeeNumber;
OleDbCommand myCommand =
new
OleDbCommand();
myCommand.CommandText = query;
myCommand.Connection = myConnection;
myCommand.ExecuteNonQuery();
myConnection.Close();
MessageBox.Show(
"Updated."
);
}
private
void
button4_Click(
object
sender, EventArgs e)
{
string
connectionString =
"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=..\\..\\Employee.mdb"
;
OleDbConnection myConnection =
new
OleDbConnection(connectionString);
string
query =
"select * from EMPLOYEE_TABLE"
;
OleDbDataAdapter myAdapter =
new
OleDbDataAdapter(query, myConnection);
DataSet employeeData =
new
DataSet();
myAdapter.Fill(employeeData);
foreach
(DataTable table
in
employeeData.Tables)
{
foreach
(DataRow row
in
table.Rows)
{
MessageBox.Show(
"Employee Number : "
+ row[
"EmployeeNumber"
].ToString());
MessageBox.Show(
"Name : "
+ row[
"Name"
].ToString());
MessageBox.Show(
"Address : "
+ row[
"Address"
].ToString());
}
}
}
private
bool
ValidateInputs()
{
try
{
int
employeeNumber =
int
.Parse(txtEmployeeNumber.Text);
}
catch
{
MessageBox.Show(
"Please enter a valid number for employee number."
,
"Error"
, MessageBoxButtons.OK, MessageBoxIcon.Warning);
txtEmployeeNumber.Focus();
txtEmployeeNumber.Select();
return
false
;
}
return
true
;
}
}