C# ПІДРУЧНИКИ / c# / Premier Press - C# Professional Projects
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The SkyShark Airlines application enforces this constraint by using Session variables. The role of the user is queried from these variables in the Load event of all forms. When the role of the user matches with the intended audience of the form, the user is allowed to load the Web form. If the user should not be allowed to access the page, the user is redirected to the default.aspx page.The code that controls access to Web pages in the Load event of forms for network administrators is given as follows:
private void Page_Load(object sender, System.EventArgs e)
{
if (Session[“usrRole”]==null)
{
Response.Redirect(“..\\default.aspx”);
}
if (!(Session[“usrRole”].ToString()==”Admin”))
{
Response.Redirect(“..\\default.aspx”);
}
else
{
txtUser.Text=”Changing password for “+ Session[“usrName”].ToString();
}
}
NOTE
You need to add the code given here in the Load event of all forms. The only precaution you need to take is that you should change the value to check in the if clause ((!(Session[“usrRole”].ToString()==”Admin”))) to “BA” for business managers and “LOB” for LOB executives.
500 Project 4 CREATING AN AIRLINE RESERVATION PORTAL
Coding the Forms for
Business Managers
Business managers use the AddFl.aspx, RequestID.aspx, Reports.aspx, and FreqFl.aspx forms for their business operations. In this section, you can learn to add functionality to these forms.
The AddFl.aspx Form
The AddFl.aspx form is used for adding details of new flights. To add data to the AddFl.aspx table, configure SqlConnection and SqlDataAdapter controls by dragging the dtFltDetails table to the form. Next, change the SelectCommand and InsertCommand properties of the sqlDataAdapter1 control as mentioned here:
SelectCommand= SELECT FltNo FROM dtFltDetails
InsertCommand= INSERT INTO dtFltDetails (FltNo, Origin,
Destination, Deptime, Arrtime, AircraftType, SeatsExec, SeatsBn, FareExec, FareBn, LaunchDate) VALUES (@FltNo, @Origin, @Destination, @Deptime, @Arrtime, @AircraftType, @SeatsExec, @SeatsBn, @FareExec, @FareBn, @LaunchDate)
The steps to add new flights to the airline are as follows:
1.Ensure that the flight number is unique. The flight number specified by the business manager is queried in the dtFltDetails table. If the flight number is not unique, an error message is displayed to the user. You need to write the following code to ensure that the flight number is unique:
dataSet11.Clear(); sqlConnection1.Open(); sqlDataAdapter1.Fill(dataSet11,”FltNos”); sqlConnection1.Close();
foreach (DataRow myRow in dataSet11.Tables[“FltNos”].Rows)
{
if (myRow[0].ToString().Trim().ToLower()==txtFltNo.Text.ToLower())
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{
lblMessage.Text=”The flight already exists. Please try another
flight number.”;
return;
}
}
2.Validate the departure and arrival times. The departure and arrival times for flights need to be specified in the correct format. The departure and arrival times specified by the user are converted into date and time format by using the ToDateTime function of the Convert class. The resultant values are stored in TimeSpan structures. The code to validate departure and arrival times is given as follows:
TimeSpan deptime, arrtime; try
{
deptime=Convert.ToDateTime(txtDepTime.Text).TimeOfDay; arrtime=Convert.ToDateTime(txtDepTime.Text).TimeOfDay;
}
catch
{
lblMessage.Text=”Invalid departure or arrival time”; return;
}
3.Update flight details. The details of the new flight are added as parameters to the InsertCommand query. Next, you need to open the connection to the database and execute the query. Then you can close the connection to the database and clear all fields of the AddFl.aspx form. The code snippet to update flight details is given as follows:
try
{
sqlDataAdapter1.InsertCommand.Parameters[0].Value=txtFltNo.Text.Trim(); sqlDataAdapter1.InsertCommand.Parameters[1].Value=txtOrigin.Text.Trim(); sqlDataAdapter1.InsertCommand.Parameters[2].Value=txtDestination.
Text.Trim();
sqlDataAdapter1.InsertCommand.Parameters[3].Value=deptime.ToString(); sqlDataAdapter1.InsertCommand.Parameters[4].Value=arrtime.ToString();
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The form also includes a Cancel button that is used to clear the values of all fields. The code for the Click event of the Cancel button is given as follows:
private void btnCancel_Click(object sender, System.EventArgs e)
{
txtFareBn.Text=””; txtFareExec.Text=””; txtSeatsBus.Text=””; txtSeatsExec.Text=””; txtArrTime.Text=””; txtDepTime.Text=””; txtDestination.Text=””; txtOrigin.Text=””; txtFltNo.Text=””; txtAircraft.Text=””;
}
The RequestID.aspx Form
The RequestID.aspx form is used for making a request for a new user account. The business manager specifies the username and the role of the new user and submits the request to the network administrator by e-mail. The code for the Click event of the Submit button is given as follows:
private void btnSubmit_Click(object sender, System.EventArgs e)
{
string to, from, subject, body; to=”admin@skyshark.com”; from=Session[“usrName”].ToString() + “@niit.com”;
subject=”New User Request”;
body=”I would like to request for a new user. The details are given below:\n\n”+
“User Name: “ + txtUserID.Text + “\n\nRole: “ + lstRole.SelectedItem.Text + “\n\nThanks!\n\n” + Session[“usrName”].ToString();
SmtpMail.Send(from, to, subject, body); txtUserID.Text=””; lstRole.SelectedIndex=0;
lblMessage.Text=”Request sent successfully”;
}
504 Project 4 CREATING AN AIRLINE RESERVATION PORTAL
The Reports.aspx Form
The Reports.aspx form is used for generating reports. The SkyShark Airlines application supports three reports.I have added three SqlDataAdapter controls on the form; one for each report. To add three SqlDataAdapter controls to the form,
drag the dtPassengerDetails and dtDepartedFlights tables to the form. I have
added the dtPassengerDetails table to the Component Designer twice so that I can configure two sqlDataAdapter controls for the application. The SelectCommand queries associated with each sqlDataAdapter control are given as follows:
sqlDataAdapter1. SELECT FltNo, SUM(Fare) AS Fare FROM dtDepartedFlights WHERE (DateOfJourney > @date) GROUP BY FltNo
sqlDataAdapter2. SELECT FltNo, DateOfJourney, SUM(Fare) AS Revenue FROM dtDepartedFlights GROUP BY DateOfJourney, FltNo
sqlDataAdapter3. SELECT TOP 100 EMail, FareCollected, TotalTimesFlown FROM dtPassengerDetails ORDER BY TotalTimesFlown
In the preceding list, the sqlDataAdapter1 control is used for generating the total revenue report. The total revenue report displays the total revenue generated by each flight after a specified date. The sqlDataAdapter2 control is used for generating the flight usage report for all flights flown by the airline. The flight usage report displays the total daily revenue generated by each flight. Finally, the sqlDataAdapter3 control is used for identifying the top 100 customers who have flown the airline most frequently.
For generating the total revenue report, you need to specify a date from which the report should be generated. After you select the date and click on Generate, the following sequence of steps generates the report:
1.The date is constructed by retrieving the month and year selected by the user and appending 01 to the date. Therefore, if the user has selected the month 07 and the year 2003, the date generated will be 07/01/2003, in the mm/dd/yyyy format.
2.The generated date is passed to the SelectCommand query of sqlDataAdapter1 as a parameter and the result is retrieved in a dataset.
3.The table in the dataset is associated with an object of the DataView class, which is bound to the DataGrid1 control to display the output report to the user.
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The code to generate the total revenue report is given as follows:
private void Button4_Click(object sender, System.EventArgs e)
{
dataSet21.Clear(); DataGrid1.DataSource=””; string month, date, year;
month=lstMonth.SelectedItem.Text; year=lstYear.SelectedItem.Text; date=month + “/01/” + year; sqlConnection1.Open();
sqlDataAdapter1.SelectCommand.Parameters[0].Value=date; sqlDataAdapter1.Fill(dataSet21,”Revenue”); sqlConnection1.Close();
DataView source=new DataView(dataSet21.Tables[“Revenue”]);
DataGrid1.DataSource=source;
DataGrid1.DataBind();
}
The flight usage report does not accept any information from the user because it generates a report for all the flights.The code for this report is straightforward, as given here:
private void Button1_Click(object sender, System.EventArgs e)
{
dataSet21.Clear(); DataGrid1.DataSource=””; sqlConnection1.Open(); sqlDataAdapter2.Fill(dataSet21,”Usage”);
DataView source=new DataView(dataSet21.Tables[“Usage”]);
DataGrid1.DataSource=source;
DataGrid1.DataBind(); sqlConnection1.Close();
}
506 Project 4 CREATING AN AIRLINE RESERVATION PORTAL
Finally, the code of the customer affinity report, which queries the top 100 customers who have flown the airline, is given as follows:
private void Button3_Click(object sender, System.EventArgs e)
{
dataSet21.Clear(); DataGrid1.DataSource=””; sqlConnection1.Open(); sqlDataAdapter3.Fill(dataSet21,”FreqFl”);
DataView source=new DataView(dataSet21.Tables[“FreqFl”]);
DataGrid1.DataSource=source;
DataGrid1.DataBind();
sqlConnection1.Close();
}
The FreqFl.aspx Form
The FreqFl.aspx form is used for enabling the frequent flier program. This form is very similar to the Reports.aspx form in its appearance and functionality. The FreqFl.aspx form enables two types of frequent flier programs. In the first program, customers who have flown the airline more than a predetermined number of times are given discounts. In the second program, customers who have paid more than a specified fare are given discounts.
To create the frequent flier programs, I have added an SqlConnection1 control to the form. Next, I have written the following function for enabling discounts to customers based on the number of times that they have flown the airline:
private void Button2_Click(object sender, System.EventArgs e)
{
lblMessage.Text=””; DataGrid1.DataSource=””;
SqlCommand Command1= new SqlCommand(“INSERT INTO dtFrequentFliers Select
EMail, Discount=”+lstDisc1.SelectedItem.Text+ “ from dtPassengerDetails where TotalTimesFlown > “+ lstTimesFlown.SelectedItem.Text, sqlConnection1);
sqlConnection1.Open(); Command1.ExecuteNonQuery(); lblMessage.Text=”Done.”;
SqlDataAdapter DataAdapter = new SqlDataAdapter(“SELECT * from dtFrequentFliers”, sqlConnection1);
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DataSet ds= new DataSet();
DataAdapter.Fill(ds);
DataView source = new DataView(ds.Tables[0]);
DataGrid1.DataSource=source;
DataGrid1.DataBind();
sqlConnection1.Close();
}
In the preceding code, I have assigned an SQL query to an object of the SqlDataAdapter class.The query is run and the rows returned are stored in an object of the DataSet class. These rows are displayed on the form by using the DataGrid1 control.
The code for the second frequent fliers program is very similar to the code for the frequent flier program already shown. However, the query that is used for retrieving the records from the database is different. The complete code of the function that retrie ves passengers for the frequent fliers program on the basis of the fare that they have paid is given as follows:
private void Button1_Click(object sender, System.EventArgs e)
{
lblMessage.Text=””;
if (txtFare.Text==”” || txtFare.Text==null)
{
lblMessage.Text=”Invalid parameter for fare collected.”; return;
}
DataGrid1.DataSource=””;
SqlCommand Command1= new SqlCommand(“INSERT INTO dtFrequentFliers Select EMail, Discount=”+lstDisc2.SelectedItem.Text+ “ from dtPassengerDetails where FareCollected > “+ txtFare.Text, sqlConnection1);
sqlConnection1.Open(); Command1.ExecuteNonQuery(); lblMessage.Text=”Done.”;
SqlDataAdapter DataAdapter = new SqlDataAdapter(“SELECT * from dtFrequentFliers”, sqlConnection1);
DataSet ds= new DataSet();
DataAdapter.Fill(ds);