Home > Articles

  • Print
  • + Share This
This chapter is from the book

This chapter is from the book

PocketSurvey

So far we've seen some of the code that drives the Web service: the back-end code, the database tier, and the code that makes the Windows Forms application possible. Now let's take a look at some of the code that was written for the PocketSurvey application.

As we discussed in Chapter 2, "Using the Survey Development Suite," PocketSurvey is an application that loads a survey profile and then lets people enter their responses. It is designed to take responses to the same survey profile over and over again, assisting survey administrators in conducting a survey run in remote locations such as shopping malls, outside movie theaters, and so on.

The two things that make this application possible are dynamically generated forms and the ability to store and retrieve data on the Pocket PC device.

Code Tour: Dynamic Forms with the DynaFormHelper Class

Dynamically generated forms are possible because of the fact that we can do programmatically everything that the designer can do. This includes creation of controls, placement and sizing of controls, and everything else you want to do with controls. In fact, if you expand the region-collapsed area of C# code that the Visual Studio .NET designer creates for you, you see all the code statements that create everything that the designer has done in the design view.

All the dynamic form creation for the PocketSurvey application is made possible through the use of a helper class. This helper class, as shown in Listing 3.14, is responsible for taking information about a question and creating the appropriate input controls on the form to deal with that question. To do this, it uses four main methods:

  • Initialize_SingleNumericQuestion

  • Initialize_NumberListQuestion

  • Initialize_CheckboxQuestion

  • Initialize_RadioQuestion

These methods create and position all the input controls necessary to prompt a respondent for the answer to a question. Listing 3.14 shows the DynaFormHelper class.

Listing 3.14 SurveyV1\PocketSurvey\DynaFormHelper.cs The DynaFormHelper Class

using System;
using System.Drawing;
using System.Windows.Forms;
using System.ComponentModel;
using System.Collections;

using SAMS.Survey.Studio.Library;

namespace SAMS.Survey.PocketSurvey
{
public class DynaFormHelper
{
 private static void InitializeQuestion( frmBlank blank, string question )
 {
  Label lblQuestion = new Label();
  lblQuestion.Text = question;
  lblQuestion.Location = new Point(8, 8);
  lblQuestion.Width = blank.Width - 10;
  lblQuestion.Height = 30;
  blank.Controls.Add( lblQuestion );
 }

 public static void Initialize_SingleNumericQuestion( frmBlank blank, string question )
 {
  InitializeQuestion( blank, question );

  TextBox tb = new TextBox();
  tb.Width = 32;
  tb.Location = new Point(8, 40);
  blank.Controls.Add( tb );
 }

 public static void Initialize_NumberListQuestion( 
    frmBlank blank, 
    string question, string[] options )
 {
  InitializeQuestion( blank, question );

  int yOffset = 40;

  foreach (string option in options)
  {
  TextBox tb = new TextBox();
  tb.Width = 16;
  tb.Location = new Point(8, yOffset);
  blank.Controls.Add( tb );
  Label lblOption = new Label();
  lblOption.Text = option;
  lblOption.Location = new Point(30, yOffset +2);
  yOffset += 22;
  blank.Controls.Add( lblOption );
  }

 }

 public static void Initialize_CheckboxQuestion( 
  frmBlank blank, string question, 
  string[] options )
 {
  InitializeQuestion( blank, question );
  int yOffset = 40;

  foreach (string option in options)
  {
   CheckBox cb = new CheckBox();
   cb.Text = option;
   cb.Location = new Point(8, yOffset);
   cb.Checked = false;
   blank.Controls.Add( cb );
   yOffset += 20;
  }
 }

 public static void Initialize_RadioQuestion( 
  frmBlank blank, string question, string[] options )
 {
  InitializeQuestion( blank, question );

  int yOffset = 34;
  Panel pnl = new Panel();
  pnl.Location = new Point(0, yOffset);
  pnl.Height = blank.Height - yOffset - 23;
  pnl.Width = blank.Width;
  blank.Controls.Add(pnl);
 
  foreach (string option in options)
  {
   RadioButton rb = new RadioButton();
   rb.Text = option;
   rb.Checked = false;
   rb.Location = new Point(8, yOffset);
   pnl.Controls.Add( rb );
   yOffset += 20;
  }
 }

 public static void Initialize_DynaForm( frmBlank blank, 
  QuestionType questionType, string question, string[] options )
 {
  blank.QuestionType = questionType;

  switch (questionType)
  {
   case QuestionType.ChoiceListMultipleAnswers:
  // this should be a checkbox next to each response option
  Initialize_CheckboxQuestion( blank, question, options );
  break;
   case QuestionType.ChoiceListNumericalRank:
  // this should be a text box next to each response option
  Initialize_NumberListQuestion( blank, question, options );
  break;
   case QuestionType.Essay:
  // there should be no initialization for essay questions
  break;
   case QuestionType.MultipleChoiceSingleAnswer:
  Initialize_RadioQuestion( blank, question, options );
  break;
   case QuestionType.SingleResponseNumericalRank:
  Initialize_SingleNumericQuestion(blank, question );
  break;
  }
 }
 }
}

Now that we've looked at the helper class, let's take a look at the code that makes use of the helper class. When the PocketSurvey application starts up, there is a Take Survey button on the main form. When you click this button, the event handler in Listing 3.15 is triggered.

Listing 3.15 SurveyV1\PocketSurvey\frmMain.cs The Take Survey Button Click Event Handler

private void btnStart_Click(object sender, System.EventArgs e)
{
 SAMS.Survey.Studio.Library.QuestionType questionType;
 string questionText;

 DataRow newSheet = dsRun.Tables["ResponseSheets"].NewRow();
 newSheet["DateEntered"] = DateTime.Now;
 newSheet["Source"] = "PocketSurvey";
 dsRun.Tables["ResponseSheets"].Rows.Add( newSheet );

 // for each question in the profile, prompt the user for a response
 // then store the responses in a new run
 foreach ( DataRow question in dsProfile.Tables["Questions"].Rows )
 {
  // obtain the question type
  questionType = (SAMS.Survey.Studio.Library.QuestionType)((int)question["Type"]);
  questionText = (string)question["LongText"];
  int choiceListId = (int)question["ChoiceListId"];
  string[] options = null;
  if (choiceListId > 0)
  {
   DataRow[] items = 
    dsProfile.Tables["ChoiceListItems"].Select("ChoiceListId=" +
    choiceListId.ToString());
   options = new string[ items.Length ];
   int i=0;
   foreach (DataRow item in items)
   {
    options[i] = item["Description"].ToString();
    i++;
    }
  }
  // grab the options (if any)
  frmBlank blankForm = new frmBlank();
  blankForm.Text = question["ShortDescription"].ToString();
  DynaFormHelper.Initialize_DynaForm( blankForm, questionType, questionText, options );
  if (blankForm.ShowDialog() == DialogResult.OK)
  {
   // do something with the result
   string response = blankForm.Response;
   DataRow newResponse = dsRun.Tables["Responses"].NewRow();
   newResponse["QuestionId"] = (int)question["ID"];
   newResponse["SheetId"] = (int)newSheet["SheetId"];
   newResponse["ResponseData"] = response;
   dsRun.Tables["Responses"].Rows.Add( newResponse );
  }
 }
 dsRun.AcceptChanges();
 dsRun.WriteXml( @"\Program Files\PocketSurvey\CurrentRun.svr" );
 }
}

In a couple pieces of Listing 3.15, it might not be immediately obvious what is going on. Before this button is even clicked, the survey profile has been loaded from disk (you'll see this code in the next section), and if there is data existing for the current run, that information has also been loaded from disk.

The basic logic is this: For each question loaded in the profile, a dynamic form is created and displayed, the response to that form is then stored, and the form is destroyed when the user clicks Next.

Code Tour: Data Storage

Data storage gave me a bit of a challenge that I wasn't expecting. Having spent so much of my time with .NET using typed data sets, I naturally assumed that I would be able to use typed data sets within the Compact Framework.

The truth is that typed data sets are not supported in the Compact Framework. Even if you attempt to take the class generated by a standard typed data set and compile it within the Compact Framework, it won't work. Getting something resembling a typed data set to work involves a considerable amount of time and effort. Another issue I had was that you can't automatically reuse assemblies between the .NET Framework and the Compact Framework. The reason for this is that the references are strongly typed. What this boils down to is that if your .NET Framework assembly references System.Data, it references a nonportable, platform-specific System.Data namespace. When you build a Compact Framework project, it might also reference System.Data, but that assembly is not the same assembly as the System.Data namespace referenced by a standard Windows Forms application. If you attempt to use an assembly with a platform-specific assembly reference on a mobile device, at best it will simply not load, and at worst it could cause your application to fail.

All I wanted was to be able to verify that the XML that I was loading was of a format that guaranteed my software the capability to load a profile and take response sheets. For that, I could do with some simple schema validation.

Because I didn't want to have any more file dependencies than necessary, I took the XSD that I used to build the typed data set for Survey Development Studio and embedded it directly in the assembly for the PocketSurvey application. In Listing 3.16 you'll see some of the initialization code from PocketSurvey, including the code that creates a schema-backed data set from the assembly-embedded XSD.

Listing 3.16 SurveyV1\PocketSurvey\frmMain.cs The Initialization Code for PocketSurvey

public frmMain()
{
 InitializeComponent();
 Stream s = 
  Assembly.GetExecutingAssembly().GetManifestResourceStream(
   "SAMS.Survey.PocketSurvey.SurveyProfile.xsd");
  XmlTextReader xr = new XmlTextReader( s );
  dsProfile = new DataSet();
  dsProfile.ReadXmlSchema( xr );
  xr.Close();
  s.Close();

  dsRun = new DataSet();
  s =   Assembly.GetExecutingAssembly().GetManifestResourceStream(
   "SAMS.Survey.PocketSurvey.SurveyRun.xsd");
  xr = new XmlTextReader( s );
  dsRun.ReadXmlSchema( xr );
  xr.Close();
  s.Close();

  dsProfile.ReadXml( @"\Program Files\PocketSurvey\CurrentSurvey.svp" );
  lblCurrent.Text = 
   "Current Profile: " + dsProfile.Tables["Profile"].Rows[0]["Title"].ToString() +
   "\n\r" + dsProfile.Tables["Profile"].Rows[0]["Notes"].ToString();

  if (File.Exists( @"\Program Files\PocketSurvey\CurrentRun.svr" ) )
  {
   dsRun.ReadXml( @"\Program Files\PocketSurvey\CurrentRun.svr" );
  }
}

In Listing 3.16 you can see that we're using GetManifestResourceStream to take hold of the embedded XSD file that we compiled into the assembly. Then a data set is created, and that schema is read into the profile data set. This ensures that no attempt to load invalid XML will ever succeed. If the load succeeds, the data conforms to the format and requirements of a proper survey profile.

If a current run (that is, collection of response sheets) is found in the application directory, the contents are loaded into memory. This is done because each time someone supplies a response to the system, the data set (dsRun) is written to disk.

  • + Share This
  • 🔖 Save To Your Account

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.

Overview


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information


To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.

Surveys

Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.

Newsletters

If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information


Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.

Security


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.

Children


This site is not directed to children under the age of 13.

Marketing


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information


If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.

Choice/Opt-out


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information


Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents


California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure


Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.

Links


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact


Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice


We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020