Copying and Pasting cs Code
In cs, like in almost any computer programming language, reading data from a file can be tricky. You add extra lines of code to tell the computer what to do. Sometimes you can copy and paste these lines from other peoples’ code.
For example, you can follow the pattern in this listing: private void btnOK_Click(object sender, EventArgs e)
{
if (txtUserName.Text == "")
{
MessageBox.Show("Please enter user name", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
txtUserName.Focus();
return;
}
if (txtPassword.Text == "")
{
MessageBox.Show("Please enter password", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
txtPassword.Focus();
return;
}
try
{
SqlConnection myConnection = default(SqlConnection);
myConnection = new SqlConnection(cs.DBConn);
SqlCommand myCommand = default(SqlCommand);
myCommand = new SqlCommand("SELECT Username,password FROM Registration WHERE Username = @username AND password = @UserPassword", myConnection);
SqlParameter uName = new SqlParameter("@username", SqlDbType.VarChar);
SqlParameter uPassword = new SqlParameter("@UserPassword", SqlDbType.VarChar);
uName.Value = txtUserName.Text;
uPassword.Value = txtPassword.Text;
myCommand.Parameters.Add(uName);
myCommand.Parameters.Add(uPassword);
myCommand.Connection.Open();
SqlDataReader myReader = myCommand.ExecuteReader(CommandBehavior.CloseConnection);
if (myReader.Read() == true)
{
int i;
ProgressBar1.Visible = true;
ProgressBar1.Maximum = 5000;
ProgressBar1.Minimum = 0;
ProgressBar1.Value = 4;
ProgressBar1.Step = 1;
for (i = 0; i <= 5000; i++)
{
ProgressBar1.PerformStep();
}
con = new SqlConnection(cs.DBConn);
con.Open();
string ct = "select usertype from Registration where Username='" + txtUserName.Text + "' and Password='" + txtPassword.Text + "'";
cmd = new SqlCommand(ct);
cmd.Connection = con;
rdr = cmd.ExecuteReader();
if (rdr.Read())
{
txtUserType.Text = (rdr.GetString(0));
}
if ((rdr != null))
{
rdr.Close();
}
if (txtUserType.Text.Trim()== "Admin")
{
this.Hide();
frm.masterEntryToolStripMenuItem.Enabled=true;
frm.usersToolStripMenuItem.Enabled=true;
frm.customerToolStripMenuItem1.Enabled=true;
frm.suppliersToolStripMenuItem.Enabled=true;
frm.productsToolStripMenuItem.Enabled=true;
frm.recordsToolStripMenuItem.Enabled=true;
frm.registrationToolStripMenuItem.Enabled=true;
frm.databaseToolStripMenuItem.Enabled=true;
frm.customerToolStripMenuItem.Enabled=true;
frm.supplierToolStripMenuItem.Enabled=true;
frm.productToolStripMenuItem.Enabled=true;
frm.stockToolStripMenuItem.Enabled=true;
frm.invoiceToolStripMenuItem.Enabled = true;
frm.Show();
frm.lblUser.Text = txtUserName.Text;
frm.lblUserType.Text = txtUserType.Text;
}
if (txtUserType.Text.Trim() == "Sales Person")
{
frm.masterEntryToolStripMenuItem.Enabled = false;
frm.usersToolStripMenuItem.Enabled = false;
frm.customerToolStripMenuItem1.Enabled = true;
frm.suppliersToolStripMenuItem.Enabled = false;
frm.productsToolStripMenuItem.Enabled = false;
frm.recordsToolStripMenuItem.Enabled = false;
frm.registrationToolStripMenuItem.Enabled = false;
frm.databaseToolStripMenuItem.Enabled = false;
frm.customerToolStripMenuItem.Enabled = true;
frm.supplierToolStripMenuItem.Enabled = false;
frm.productToolStripMenuItem.Enabled = false;
frm.stockToolStripMenuItem.Enabled = false;
frm.invoiceToolStripMenuItem.Enabled = true;
this.Hide();
frm.Show();
frm.lblUser.Text = txtUserName.Text;
frm.lblUserType.Text = txtUserType.Text;
}
if (txtUserType.Text.Trim() == "Warehouse Worker")
{
frm.masterEntryToolStripMenuItem.Enabled = false;
frm.usersToolStripMenuItem.Enabled = false;
frm.customerToolStripMenuItem1.Enabled = false;
frm.suppliersToolStripMenuItem.Enabled = false;
frm.productsToolStripMenuItem.Enabled = false;
frm.recordsToolStripMenuItem.Enabled = false;
frm.registrationToolStripMenuItem.Enabled = false;
frm.databaseToolStripMenuItem.Enabled = false;
frm.customerToolStripMenuItem.Enabled = false;
frm.supplierToolStripMenuItem.Enabled = false;
frm.productToolStripMenuItem.Enabled = false;
frm.stockToolStripMenuItem.Enabled = false;
frm.invoiceToolStripMenuItem.Enabled = false;
this.Hide();
frm.Show();
frm.lblUser.Text = txtUserName.Text;
frm.lblUserType.Text = txtUserType.Text;
}
if (txtUserType.Text.Trim() == "Warehouse Manager")
{
frm.masterEntryToolStripMenuItem.Enabled = false;
frm.usersToolStripMenuItem.Enabled = false;
frm.customerToolStripMenuItem1.Enabled = false;
frm.suppliersToolStripMenuItem.Enabled = false;
frm.productsToolStripMenuItem.Enabled = false;
frm.recordsToolStripMenuItem.Enabled = false;
frm.registrationToolStripMenuItem.Enabled = false;
frm.databaseToolStripMenuItem.Enabled = false;
frm.customerToolStripMenuItem.Enabled = false;
frm.supplierToolStripMenuItem.Enabled = true;
frm.productToolStripMenuItem.Enabled = true;
frm.stockToolStripMenuItem.Enabled = true;
frm.invoiceToolStripMenuItem.Enabled = false;
this.Hide();
frm.Show();
frm.lblUser.Text = txtUserName.Text;
frm.lblUserType.Text = txtUserType.Text;
}
if (txtUserType.Text.Trim() == "Customer")
{
frmCustomerMainMenu frm1 = new frmCustomerMainMenu();
this.Hide();
frm1.Show();
frm1.lblUser.Text = txtUserName.Text;
}
}
else
{
MessageBox.Show("Login is Failed...Try again !", "Login Denied", MessageBoxButtons.OK, MessageBoxIcon.Error);
txtUserName.Clear();
txtPassword.Clear();
txtUserName.Focus();
}
if (myConnection.State == ConnectionState.Open)
{
myConnection.Dispose();
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
{
if (txtUserName.Text == "")
{
MessageBox.Show("Please enter user name", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
txtUserName.Focus();
return;
}
if (txtPassword.Text == "")
{
MessageBox.Show("Please enter password", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
txtPassword.Focus();
return;
}
try
{
SqlConnection myConnection = default(SqlConnection);
myConnection = new SqlConnection(cs.DBConn);
SqlCommand myCommand = default(SqlCommand);
myCommand = new SqlCommand("SELECT Username,password FROM Registration WHERE Username = @username AND password = @UserPassword", myConnection);
SqlParameter uName = new SqlParameter("@username", SqlDbType.VarChar);
SqlParameter uPassword = new SqlParameter("@UserPassword", SqlDbType.VarChar);
uName.Value = txtUserName.Text;
uPassword.Value = txtPassword.Text;
myCommand.Parameters.Add(uName);
myCommand.Parameters.Add(uPassword);
myCommand.Connection.Open();
SqlDataReader myReader = myCommand.ExecuteReader(CommandBehavior.CloseConnection);
if (myReader.Read() == true)
{
int i;
ProgressBar1.Visible = true;
ProgressBar1.Maximum = 5000;
ProgressBar1.Minimum = 0;
ProgressBar1.Value = 4;
ProgressBar1.Step = 1;
for (i = 0; i <= 5000; i++)
{
ProgressBar1.PerformStep();
}
con = new SqlConnection(cs.DBConn);
con.Open();
string ct = "select usertype from Registration where Username='" + txtUserName.Text + "' and Password='" + txtPassword.Text + "'";
cmd = new SqlCommand(ct);
cmd.Connection = con;
rdr = cmd.ExecuteReader();
if (rdr.Read())
{
txtUserType.Text = (rdr.GetString(0));
}
if ((rdr != null))
{
rdr.Close();
}
if (txtUserType.Text.Trim()== "Admin")
{
this.Hide();
frm.masterEntryToolStripMenuItem.Enabled=true;
frm.usersToolStripMenuItem.Enabled=true;
frm.customerToolStripMenuItem1.Enabled=true;
frm.suppliersToolStripMenuItem.Enabled=true;
frm.productsToolStripMenuItem.Enabled=true;
frm.recordsToolStripMenuItem.Enabled=true;
frm.registrationToolStripMenuItem.Enabled=true;
frm.databaseToolStripMenuItem.Enabled=true;
frm.customerToolStripMenuItem.Enabled=true;
frm.supplierToolStripMenuItem.Enabled=true;
frm.productToolStripMenuItem.Enabled=true;
frm.stockToolStripMenuItem.Enabled=true;
frm.invoiceToolStripMenuItem.Enabled = true;
frm.Show();
frm.lblUser.Text = txtUserName.Text;
frm.lblUserType.Text = txtUserType.Text;
}
if (txtUserType.Text.Trim() == "Sales Person")
{
frm.masterEntryToolStripMenuItem.Enabled = false;
frm.usersToolStripMenuItem.Enabled = false;
frm.customerToolStripMenuItem1.Enabled = true;
frm.suppliersToolStripMenuItem.Enabled = false;
frm.productsToolStripMenuItem.Enabled = false;
frm.recordsToolStripMenuItem.Enabled = false;
frm.registrationToolStripMenuItem.Enabled = false;
frm.databaseToolStripMenuItem.Enabled = false;
frm.customerToolStripMenuItem.Enabled = true;
frm.supplierToolStripMenuItem.Enabled = false;
frm.productToolStripMenuItem.Enabled = false;
frm.stockToolStripMenuItem.Enabled = false;
frm.invoiceToolStripMenuItem.Enabled = true;
this.Hide();
frm.Show();
frm.lblUser.Text = txtUserName.Text;
frm.lblUserType.Text = txtUserType.Text;
}
if (txtUserType.Text.Trim() == "Warehouse Worker")
{
frm.masterEntryToolStripMenuItem.Enabled = false;
frm.usersToolStripMenuItem.Enabled = false;
frm.customerToolStripMenuItem1.Enabled = false;
frm.suppliersToolStripMenuItem.Enabled = false;
frm.productsToolStripMenuItem.Enabled = false;
frm.recordsToolStripMenuItem.Enabled = false;
frm.registrationToolStripMenuItem.Enabled = false;
frm.databaseToolStripMenuItem.Enabled = false;
frm.customerToolStripMenuItem.Enabled = false;
frm.supplierToolStripMenuItem.Enabled = false;
frm.productToolStripMenuItem.Enabled = false;
frm.stockToolStripMenuItem.Enabled = false;
frm.invoiceToolStripMenuItem.Enabled = false;
this.Hide();
frm.Show();
frm.lblUser.Text = txtUserName.Text;
frm.lblUserType.Text = txtUserType.Text;
}
if (txtUserType.Text.Trim() == "Warehouse Manager")
{
frm.masterEntryToolStripMenuItem.Enabled = false;
frm.usersToolStripMenuItem.Enabled = false;
frm.customerToolStripMenuItem1.Enabled = false;
frm.suppliersToolStripMenuItem.Enabled = false;
frm.productsToolStripMenuItem.Enabled = false;
frm.recordsToolStripMenuItem.Enabled = false;
frm.registrationToolStripMenuItem.Enabled = false;
frm.databaseToolStripMenuItem.Enabled = false;
frm.customerToolStripMenuItem.Enabled = false;
frm.supplierToolStripMenuItem.Enabled = true;
frm.productToolStripMenuItem.Enabled = true;
frm.stockToolStripMenuItem.Enabled = true;
frm.invoiceToolStripMenuItem.Enabled = false;
this.Hide();
frm.Show();
frm.lblUser.Text = txtUserName.Text;
frm.lblUserType.Text = txtUserType.Text;
}
if (txtUserType.Text.Trim() == "Customer")
{
frmCustomerMainMenu frm1 = new frmCustomerMainMenu();
this.Hide();
frm1.Show();
frm1.lblUser.Text = txtUserName.Text;
}
}
else
{
MessageBox.Show("Login is Failed...Try again !", "Login Denied", MessageBoxButtons.OK, MessageBoxIcon.Error);
txtUserName.Clear();
txtPassword.Clear();
txtUserName.Focus();
}
if (myConnection.State == ConnectionState.Open)
{
myConnection.Dispose();
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}