Microsoft Visual C++ .NET Professional Projects - Premier Press

480 Project 3 ADO.NET IN MANAGED C++

if(totallogincount==3)

{

//No row found - hence invalid login

//close the application after 3 tries are done.

T //validated

}

If the user tries to close the Login form by clicking on the Cancel button, close the application too:

void OnCancelButtonClick(Object *sender, EventArgs *e)

{

Close(); //Close the form

Application::Exit(); //Exit from the application

}

Creating the Account Details Form

Once the user has logged in successfully, the main banking form will be accessible, which will have all the GUI elements necessary for making the banking transactions. Figure 14-3 depicts the Account Details form, which is the main banking form.

Following is the declaration of the BankForm class and the variables declared in it. This class will handle the Account Details form and all other transactions in this form.

Team-Fly®

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FIGURE 14-3 The Account Details form

__gc class BankForm: public Form

{

private:

//all variable declarations to initialize the various controls that are to be

//displayed on the form

//a global variable to store the reference to the DataSet. This data set will

//be used across the application - once it has been populated

DataSet *ds;

//Create a SqlDataAdapter.

SqlDataAdapter* myAdapter;

//variable to store the number of the total records in the dataset at any point int lastrow;

//a global variable to store which is the current record no.

int currentrec;

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Once the application starts running, it will create an instance of the BankForm class, and its constructor is invoked. The constructor of the BankForm class does the following:

Creates an instance of the LoginForm class and displays it as a dialog box.

Calls the CreateControls method that will create all the controls on the form.

Calls the FetchData method that will fetch records from the database and populate the controls with the first row of the returned dataset.

Following is the code for the constructor of the BankForm class:

BankForm()

{

//create the error provider control error=new ErrorProvider(); error->BlinkRate=250;

error->BlinkStyle=ErrorBlinkStyle::BlinkIfDifferentError;

flag=false;

//setting the properties of the form caption = “Bank Operations”;

width = 600; height = 400;

//the following code calls the login form that displays a dialog box. If the user

//successfully passes through the login form, then the control will pass to the

//CreateControls function that will create the main form. On the other hand, if

//the user clicks on the Cancel button or fails to enter the correct login

//details, then exit from the application.

lgform = new LoginForm(); if(lgform->ShowDialog(this) == 1)

{

}

lgform->Dispose();

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3.The Location property is set to control the location of the control on the form.

4.The event handler method for the Click event of the button is set and the button is added to the Controls collection of the form.

The following code snippet illustrates the preceding steps:

firstbutton = new Button(); firstbutton->Text = “&<< First”; firstbutton->Size = Drawing::Size(75, 30); firstbutton->TabIndex = 0;

firstbutton->Location = Drawing::Point(width/2-180, height - 160); firstbutton->Click += (new EventHandler(this, &BankForm::OnFirstRecord)); Controls->Add(firstbutton);

All other controls are added to the form similarly. Following is the complete listing of the CreateControls method:

void CreateControls()

{

//create controls here

//FOR EACH CONTROL - the size, location etc. are set

//also specified are the function handlers for buttons

//and menu item controls

// Basic WinForm Settings

Text = caption;

Size = Drawing::Size(width, height);

// Set up Menu

mainMenu = new MainMenu(); fileMenu = new MenuItem(“&File”); mainMenu->MenuItems->Add(fileMenu);

fileMenu->MenuItems->Add(new MenuItem(“E&xit”, new EventHandler(this, &BankForm::OnFileExit)));

// create the records menu

recordmenu = new MenuItem(“&Record”); mainMenu->MenuItems->Add(recordmenu);

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prevbutton->Location = Drawing::Point(width/2-80, height - 160); prevbutton->Click += (new EventHandler(this, &BankForm::OnPrevRecord)); Controls->Add(prevbutton);

// Set up Next Record Button nextbutton = new Button(); nextbutton->Text = “& Next >”;

nextbutton->Size = Drawing::Size(75, 30); nextbutton->TabIndex = 0;

nextbutton->Location = Drawing::Point(width/2+20, height - 160); nextbutton->Click += (new EventHandler(this, &BankForm::OnNextRecord)); Controls->Add(nextbutton);

// Set up last Record Button lastbutton = new Button(); lastbutton->Text = “&Last >>”;

lastbutton->Size = Drawing::Size(75, 30); lastbutton->TabIndex = 0;

lastbutton->Location = Drawing::Point(width/2+120, height - 160); lastbutton->Click += (new EventHandler(this, &BankForm::OnLastRecord)); Controls->Add(lastbutton);

//The following pieces of code create the labels

//and the corresponding edit box for the field’s data to

//be displayed on the form

heading = new Label(); heading->Text=”First Name”; heading->Size = Drawing::Size(100, 20);

heading->Location = Drawing::Point(width/2-240, height - 360); Controls->Add(heading);

fname = new TextBox(); fname->Name=”fname”;

fname->Size = Drawing::Size(150, 40); fname->TabIndex = 2;

fname->Location = Drawing::Point(width/2-120, height - 360); Controls->Add(fname);

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Controls->Add(paddr);

heading = new Label(); heading->Text=”Mailing Address”; heading->Size = Drawing::Size(100, 20);

heading->Location = Drawing::Point(width/2-240, height - 280); Controls->Add(heading);

maddr = new TextBox(); maddr->Name=”maddr”;

maddr->Size = Drawing::Size(150, 40); maddr->TabIndex = 2;

maddr->Location = Drawing::Point(width/2-120, height - 280); Controls->Add(maddr);

heading = new Label(); heading->Text=”Phone No:”; heading->Size = Drawing::Size(100, 20);

heading->Location = Drawing::Point(width/2-240, height - 260); Controls->Add(heading);

phno = new TextBox(); phno->Name=”phno”;

phno->Size = Drawing::Size(150, 40); phno->TabIndex = 2;

phno->Location = Drawing::Point(width/2-120, height - 260); Controls->Add(phno);

heading = new Label(); heading->Text=”Email id:”; heading->Size = Drawing::Size(100, 20);

heading->Location = Drawing::Point(width/2-240, height - 240); Controls->Add(heading);

emailid = new TextBox(); emailid->Name=”emailid”;

emailid->Size = Drawing::Size(150, 40); emailid->TabIndex = 2;