1. CIS407A iLab 5 Web Application
Development Devry University
Click this link to get the tutorial:
http://homeworkfox.com/tutorials/general-
questions/6227/cis407a-ilab-5-web-application-development-
devry-university/
iLab 5 of 7: Transaction Processing (30 Points)
Submit your assignment to the Dropbox located on the silver tab at the top of this page.
(See "Due Dates for Assignments & Exams" in the Syllabus for due dates.)
iLABOVERVIEW
Scenario/Summary
This week, we will use the .NET OleDbTransaction functions to either commit a set of changes
to the database, if all of them were done correctly, or to roll back all of the changes if there was
an error in any one of them. We will first modify the code we created last week so that it saves
personnel data in the database in two steps; first by inserting a personnel record for a new
employee, and then by updating that record to fill in the start and end dates. This two-step
approach is not really needed in this simple case, but we will use it to simulate a more complex
database transaction that would have to be done in multiple steps, such as one involving more
than one table or even more than one database. We will then see what happens when there is an
error in the second operation (the update), allowing a record to be created containing incomplete
information--not a good result! We will fix the problem by wrapping both operations (the insert
and the update) into a single transaction that will be committed (made permanent) only if both
operations succeed or that will be rolled back (undone) if either operation fails. We will also add
client-side validation using the ASP.Net validation controls, and we will allow the user an easy
way to edit all employees.
Instructions for Week 5 iLab: "Transaction Processing"
Click on the link above to view the tutorial.
Please watch this tutorial before beginning the iLab.
The tutorial has audio.
Deliverables

2. All files are located in the subdirectory of the project. The project should function as specified:
When you press the Submit button in frmPersonnel, a record should be saved in the tblPersonnel
table containing the FirstName, LastName, PayRate, StartDate, and EndDate you entered. Test
that the transaction will rollback by entering invalid information in one or more items, such as
Hello for a StartDate. Check tht client-side validation works: The ability to edit employees in a
grid is working. Once you have verified that it works, save your website, zip up all files, and
submit them to the Dropbox.
iLABSTEPS
STEP 1: Modify the clsDataLayer to use a two-step process (10 points)
1. Open Microsoft Visual Studio.NET 2008.
2. Click the ASP.NET project called PayrollSystem to open it.
3. Open the clsDataLayer class.
4. Modify the SavePersonnel() function so that instead of just doing a single SQL INSERT
operation with all the personnel data, it does an INSERT with only the FirstName and LastName,
followed by an UPDATE to save the PayRate, StartDate, and EndDate into the new record. (This
two-step approach is not really necessary here because we are dealing with only one table,
tblPersonnel, but we are doing it to simulate a case with more complex processing requirements,
where we would need to insert or update data in more than one table or maybe even more than
one database.) Find the following existing code in the SavePersonnel() function:
// Add your comments here
+
"(FirstName, LastName, PayRate, StartDate, EndDate) values ('" +
FirstName + "', '" + LastName + "', " + PayRate + ", '" + StartDate +
"', '" + EndDate + "')";
// Add your comments here
;
;
// Add your comments here
command.ExecuteNonQuery();

3. 5.
Modify it so that it reads as follows:
// Add your comments here
+
"(FirstName, LastName) values ('" +
FirstName + "', '" + LastName + "')";
// Add your comments here
;
;
// Add your comments here
command.ExecuteNonQuery();
// Add your comments here
+
"Set , " +
", " +
""+
"Where ID=(Select Max(ID) From tblPersonnel)";
// Add your comments here
;
;
// Add your comments here
command.ExecuteNonQuery();
6. Set frmMain as the startup form and run the PayrollSystem Web application to test the
changes. When valid data values are entered for a new employee, things should work exactly as

4. they did before. To test this, enter valid data for a new employee in frmPersonnel and click
Submit. The frmPersonnelVerified form should be displayed with the entered data values and a
message that the record was saved successfully. Click the View Personnel button and check that
the new personnel record was indeed saved to the database and that all the entered data values,
including the PayRate, StartDate, and EndDate, were stored correctly. Close the browser
window.
7. Now run the PayrollSystem Web application again, but this time enter some invalid data (a
nonnumeric value) in the PayRate field to cause an error, like this:
Click on image to enlarge.
8.
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9. Now when you click Submit, the frmPersonnelVerified form should display a message
indicating the record was not saved:
Click on image to enlarge.
10.
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11. However, when you click on the View Personnel button to display the personnel records,
you should see that an incomplete personnel record was in fact created, with missing values for
the PayRate, StartDate and EndDate fields:
Click on image to enlarge.
12.
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13. This occurred because the Insert statement succeeded but the following Update statement
did not. We do not want to allow this to happen because we end up with incomplete or incorrect
data in the database. If the Update statement fails, we want the Insert statement to be rolled back,
or undone, so that we end up with no record at all. We will fix this by adding transaction code in
the next step.
STEP 2: Add transaction code (10 points)
7. In the clsDataLayer.cls class file, add code to the SavePersonnel() function to create a
transaction object. Begin the transaction, commit the transaction if all database operations are
successful, and roll back the transaction if any database operation fails. The following listing

5. shows the complete SavePersonnel() function; the lines you will need to add are marked with **
NEW ** in the preceding comment and are shown in bold.
// This function saves the personnel data
public static bool SavePersonnel(string Database, string FirstName, string LastName,
string PayRate, string StartDate, string EndDate)
{
bool recordSaved;
// ** NEW ** Add your comments here
OleDbTransaction ;
try
{
// Add your comments here
OleDbConnection OleDbConnection(";" +
"Data Insert into tblPersonnel " +
"(FirstName, LastName) values ('" +
FirstName + "', '" + LastName + "')";
// Add your comments here
;
;
// Add your comments here
command.ExecuteNonQuery();
// Add your comments here
+
"Set , " +

6. ", " +
""+
"Where ID=(Select Max(ID) From tblPersonnel)";
// Add your comments here
;
;
// Add your comments here
command.ExecuteNonQuery();
// ** NEW ** Add your comments here
myTransaction.Commit();
// Add your comments here
conn.Close();
;
}
catch (Exception ex)
{
// ** NEW ** Add your comments here
myTransaction.Rollback();
;
}
return recordSaved;
}
8. Run your Web application. First, enter valid data in all the fields of frmPersonnel. When you
press the Submit button in frmPersonnel, a record should be saved in the tblPersonnel table

7. containing the FirstName, LastName, PayRate, StartDate, and EndDate. With valid data entered
in all the items, the "successfully saved" message should appear indicating that the transaction
was committed.
Click on image to enlarge.
9.
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10. Click the View Personnel button and verify that the new record was in fact added to the
database table correctly.
Click on image to enlarge.
11.
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12. Now close the browser, run the Web application again, and this time test that the transaction
will roll back after entering incorrect information. On the frmPersonnel form, enter invalid data
for PayRate and click Submit. The "not saved" message should appear, which indicates that the
transaction was rolled back.
Click on image to enlarge.
13.
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14. Click the View Personnel button and verify that this time, as desired, an incomplete record
was not added to the database table.
Click on image to enlarge.
15.
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16. You have seen how we used the try/catch block to catch an unexpected error. You may have
noticed that if you enter bad data for the dates, an exception is thrown. Go back to the validation
code you added in the frmPersonnel code and add a try/catch with logic to prevent an invalid
date from causing a server error.
17. In the Week 3 and Week 5 labs, you learned how to validate code once the page was posted
back to the server. There is some validation that must be done on the server because it requires

8. server resources such as the database. Some validation can also be done on the client. If you can
do validation on the client it saves a round trip to the server, which will improve performance. In
this approach, we will check values before the page is submitted to the server for processing.
Normally, there is a combination of server and client validation used in a web application.
ASP.Net includes validation controls which will use JavaScript on the client to perform
validation. You will find these controls in the Validation group in the toolbox.
18. Add validation controls to the frmPersonnel form as follows: For the first and last name,
make sure each field has data in it. Use the RequiredFieldValidator for this. Add the control to
the right of the text box you are validating. The location of the validator control is where the
error message (if there is one) will appear for the control you link the validator to. You will be
adding one validator control for each text box you want to validate. Remember to set the
ControlToValidate and ErrorMessage properties on the validator control. Making this change
eliminates the need for the server-side check you were doing previously. Use a regular
expression validator to check that the start and end date are in the correct format.
Click on image to enlarge.
19.
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20. Remove the View Personnel and Cancel buttons from the frmPersonnel form as they will
cause a Postback and invoke the client-side editing you just added. The user is able to get to the
View Personnel from the main form and from the personnel verification screen, so there is no
need for these buttons now.
21. Because you have entered data in this lab that is invalid and those partial records are in the
database, you will need to add the ability to remove or update data. Add a new main form option
called Edit Employees. Add the link and image for this. This option will take the user to a new
form called frmEditPersonnel.
frmMain with links added
22.
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23. Add the new form frmEditPersonnel. On frmEditPersonnel, add the CoolBiz log at the top of
the form. Add a label that says "Edit Employees." Add a GridView control with an ID of
grdEditPersonnel.
24. You will now add a SQLDataSource to the page. You will be using a databound grid for this
form unlike the previous grids, in which you added as unbound (in the designer).

9. 25. Add a new SQLDataSource control to the frmEditPersonnel in the design view. This is not a
visible control; that is, it will only appear in design view but the user will never see it. Note: If
you change the folder name or location of your database, you will need to reconfigure the data
source (right-click on the data source control and select the "Configure Data Source" option.
26. There is a small > indicator in the design view of the SQL Data Source control you added if
the configuration menu is collapsed (press it to open the menu), or there is a < with the menu
displayed. From the data source menu, select "Configure Data Source."
27. Press the New Connection button and select the database.
28. Press the Next button.
29. When asked if you want to save the connection in the application configuration file, check
the Yes check box and press Next.
30. Select the tblPersonnel table.
31. Select all columns (you can use the * for this).
32. Press the Advanced button and check the Generate Insert, Update, and Delete option and
press the OK button.
33. Press the Next button.
34. Press the Test Query button and make sure everything works as it is supposed to. If it does
not repeat the above steps to make sure you did everything properly. Press the Finish button.
7. Click on the grid you added in the design view and expand the properties menu (the little > in
the upper right of the control). Choose the data source you just added. On the GridView tasks
menu, select Edit columns. Add an Edit, Update, and Cancel Command field. Add a Delete
Command field. Press OK. You can now test the grid, which is a fully functioning Update and
Delete grid. Try it out!
Click on image to enlarge.
8.
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9. Hints:
Make sure you reestablish your database connection if you copied the files from a previous lab.
In order to keep the validation controls from causing wrapping, you may want to increase the
Panel width.

10. A regular expression for mm/dd/yyyy is this:
^(0[1-9]|1[012])[- /.](0[1-9]|[12][0-9]|3[01])[- /.](19|20)dd$
Experiment with the editable grid and command buttons for different display styles.
STEP 3: Test and submit (10 points)
29. Once you have verified that everything works as it is supposed to, save your project, zip up
all files, and submit in the Dropbox.