// Method for handling going to the very first element of the list (the one with index 0) and havig is displayed:
private void initial_list_element_Click(object sender, EventArgs e)
{
if (catalogCarEntry.Count() != 0) // Making sure the list is not empty.
{
// First set the counter to 0:
counter = 0;
// Put the initial element of the catalogCarEntry list
// into the 'currentRecord' record of type RecordSerializable:
currentRecord = catalogCarEntry[counter];
// store RecordSerializable values in temporary string array
var values = new string[] {
currentRecord.Account.ToString(),
currentRecord.FirstName.ToString(),
currentRecord.LastName.ToString(),
currentRecord.Balance.ToString()
};
// copy string-array values to TextBox values
SetTextBoxValues(values);
}
else
{
MessageBox.Show("List Is Empty!", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
// Display empty text boxes:
ClearTextBoxes();
}
}
// parameterless constructor
public Form1()
{
InitializeComponent();
// Creation of a List with catalog entries which is to help
// in development and testing out the different functinalities
// of the program:
// Creation of 4 catalog entries. Please note that each entry has 4 fields,
// namely 'number in catalog', 'car brand', 'model' and 'rental cost per day'.
// var dummyRecord = new RecordSerializable(0, "", "", 0.00M);
var record1 = new RecordSerializable(1, "Ford", "Fiesta", 68.37M);
var record2 = new RecordSerializable(2, "Chevrolet", "Corvette", 232.54M);
var record3 = new RecordSerializable(3, "Dodge", "Ranger", 170.33M);
var record4 = new RecordSerializable(4, "Fiat", "Uno", 250.45M);
// Write 4 record entries into the list 'catalogCarEntry':
catalogCarEntry.Add(record1);
catalogCarEntry.Add(record2);
catalogCarEntry.Add(record3);
catalogCarEntry.Add(record4);
// Creation and initialization of a variable to measure the length
// of the list. This will serve an important purpose in checking
// errors and catching exception, like for example when the button
// 'Step Up' has been pressed too often:
int catalogLength = catalogCarEntry.Capacity;
}
} // end method openButton_Click
// invoked when user clicks Next button
private void nextButton_Click(object sender, EventArgs e)
{
// deserialize RecordSerializable and store data in TextBoxes
try
{
// get next RecordSerializable available in file
RecordSerializable record =
( RecordSerializable )reader.Deserialize(input);
// store RecordSerializable values in temporary string array
string[] values = new string[] {
record.Account.ToString(),
record.FirstName.ToString(),
record.LastName.ToString(),
record.Balance.ToString()
};
// copy string array values to TextBox values
SetTextBoxValues(values);
} // end try
// handle exception when there are no RecordSerializables in file
catch (SerializationException)
{
input.Close(); // close FileStream
openButton.Enabled = true; // enable Open File button
nextButton.Enabled = false; // disable Next Record button
ClearTextBoxes();
// notify user if no RecordSerializables in file
MessageBox.Show("No more records in file", string.Empty,
MessageBoxButtons.OK, MessageBoxIcon.Information);
} // end catch
} // end method nextButton_Click
} // end method saveButton_Click
// handler for enterButton Click
private void enterButton_Click(object sender, EventArgs e)
{
// store TextBox values string array
string[] values = GetTextBoxValues();
// RecordSerializable containing TextBox values to serialize
RecordSerializable record = new RecordSerializable();
// determine whether TextBox account field is empty
if (values[( int )TextBoxIndices.ACCOUNT] != string.Empty)
{
// store TextBox values in RecordSerializable and serialize it
try
{
// get account number value from TextBox
int accountNumber = Int32.Parse(
values[( int )TextBoxIndices.ACCOUNT]);
// determine whether accountNumber is valid
if (accountNumber > 0)
{
// store TextBox fields in RecordSerializable
record.Account = accountNumber;
record.FirstName = values[( int )
TextBoxIndices.FIRST];
record.LastName = values[( int )
TextBoxIndices.LAST];
record.Balance = Decimal.Parse(values[
( int )TextBoxIndices.BALANCE]);
// write Record to FileStream ( serialize object )
formatter.Serialize(output, record);
} // end if
else
{
// notify user if invalid account number
MessageBox.Show("Invalid Account Number", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
} // end else
} // end try
// notify user if error occurs in serialization
catch (SerializationException)
{
MessageBox.Show("Error Writing to File", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
} // end catch
// notify user if error occurs regarding parameter format
catch (FormatException)
{
MessageBox.Show("Invalid Format", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
} // end catch
} // end if
ClearTextBoxes(); // clear TextBox values
} // end method enterButton_Click
// Method for handling deletion of element:
private void delete_current_element_Click(object sender, EventArgs e)
{
if (catalogCarEntry.Count() >= 2)
{
catalogCarEntry.RemoveAt(counter);
// Now find out whether the element moved was the highest on in the list:
if ((counter + 1) > catalogCarEntry.Count()) // I added 1 to counter due to its 0 initial value.
{
counter = counter - 1;
}
// Otherwise the counter remains the same:
currentRecord = catalogCarEntry[counter];
var nowValues = new string[] {
currentRecord.Account.ToString(),
currentRecord.FirstName.ToString(),
currentRecord.LastName.ToString(),
currentRecord.Balance.ToString()
};
// Display the contents of the element indicated by the counter now:
SetTextBoxValues(nowValues);
}
else if (catalogCarEntry.Count() == 1) // If there is only one element in the element.
{
catalogCarEntry.RemoveAt(counter); // Now the list should be empty and hence only contain
// the element catalogCarEntry[0].
MessageBox.Show("You Just Removed the Last Element! Now the List is Empty!", "Announcement",
MessageBoxButtons.OK, MessageBoxIcon.Error);
counter = 0; // Counter put to zero by default. Actually there isn't any element in an empty list.
// In any case a good starting point for subsequent stages in the program.
// Display empty text boxes:
ClearTextBoxes();
}
else
{
MessageBox.Show("List Was Empty to Begin with!", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
counter = 0; // counter put to zero by default. Actually there is no elemet in an empty list.
// Display empty text boxes:
ClearTextBoxes();
}
}
// handler for enterButton Click
private void enterButton_Click(object sender, EventArgs e)
{
// store TextBox values string array
string[] values = GetTextBoxValues();
// determine whether TextBox account field is empty
if (!string.IsNullOrEmpty(values[(int)TextBoxIndices.Account]))
{
// store TextBox values in RecordSerializable and serialize it
try
{
// get account-number value from TextBox
int accountNumber = int.Parse(
values[(int)TextBoxIndices.Account]);
// determine whether accountNumber is valid
if (accountNumber > 0)
{
// RecordSerializable to serialize
var record = new RecordSerializable(accountNumber,
values[(int)TextBoxIndices.First],
values[(int)TextBoxIndices.Last],
decimal.Parse(values[(int)TextBoxIndices.Balance]));
// write Record to FileStream (serialize object)
formatter.Serialize(output, record);
}
else
{
// notify user if invalid account number
MessageBox.Show("Invalid Account Number", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
catch (SerializationException)
{
MessageBox.Show("Error Writing to File", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
catch (FormatException)
{
MessageBox.Show("Invalid Format", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
ClearTextBoxes(); // clear TextBox values
}
// Method for handling loading records from an external file (presumably .SER file) into the list named 'catalogCarEntry'
// which is for elements of type 'RecordSerializable':
private void load_from_binary_file_Click(object sender, EventArgs e)
{
// Create and show dialog box enabling user to open file:
DialogResult result; // result of OpenFileDialog.
string inputfileName;
using (OpenFileDialog inputfileChooser = new OpenFileDialog())
{
result = inputfileChooser.ShowDialog();
inputfileName = inputfileChooser.FileName; // Get specified name.
}
// Ensure that user clicked "OK":
if (result == DialogResult.OK)
{
ClearTextBoxes();
// Show error if user specified invalid file:
if (string.IsNullOrEmpty(inputfileName))
{
MessageBox.Show("Invalid File Name", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
else
{
// Create FileStream to obtain read access to file:
inputstream = new FileStream(
inputfileName, FileMode.Open, FileAccess.Read);
// openButton.Enabled = false; // disaable Open File button. (Might be irrelevant here.)
// nextButton.Enable = true; // enable Next Record button. (Might be irrelevant here.)
// In the following code stucture (which will be within this 'else' module, we will put the
// contents of the 'stream' into the 'List' nameed 'catalogCarEntry'. Of course we have
// incorporated a try and catch system, in case that 'stream' contains something that 'List'
// doesn't like.
// Deserialize:
try
{
// List<RecordSerializable> catalogCarEntry = null; // Experimental command.
// catalogCarEntry = (List<RecordSerializable>)serializer.Deserialize(inputstream);
catalogCarEntry = (List <RecordSerializable>)serializer.Deserialize(inputstream);
// Show the 0th elemet of the catalogCarEntry list, so that the boxes won't
// be empty after the loading procedure:
if (catalogCarEntry.Count() != 0) // Making sure the list is not empty.
{
// First set the counter to 0:
counter = 0;
// Put the initial element of the catalogCarEntry list
// into the 'currentRecord' record of type RecordSerializable:
currentRecord = catalogCarEntry[counter];
// store RecordSerializable values in temporary string array
var values = new string[] {
currentRecord.Account.ToString(),
currentRecord.FirstName.ToString(),
currentRecord.LastName.ToString(),
currentRecord.Balance.ToString()
};
// copy string-array values to TextBox values
SetTextBoxValues(values);
}
else
{
MessageBox.Show("List Is Empty!", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
// Display empty text boxes:
ClearTextBoxes();
}
}
catch (SerializationException)
{
inputstream?.Close(); // close FileStream
// openButon.Enabled = true; // Irrelevant here presumably.
// nextButton.Enabled = false; // Disable Next Record button.
ClearTextBoxes();
// Notify user if no RecordSerializables in file
MessageBox.Show("No more records in file", string.Empty,
MessageBoxButtons.OK, MessageBoxIcon.Information);
}
}
}
}
// Method for handling modification of element in question:
private void modify_element_Click(object sender, EventArgs e)
{
/* Here it as about trying what the getBox Method has yielded,
* and catching the string array, named values presumably, for
* for format errors.
* As for those that made it into the try block, check if the
* account value is an integer larger than 0.
*
*/
// Now lets first get the values that are (or are not) in the boxes:
string[] values = GetTextBoxValues();
// Now determine if the account field (the integer number entry in the catalog) is empty:
if (!string.IsNullOrEmpty(values[(int)TextBoxIndices.Account]))
{
// store TextBox values in the element of type RecordSerializable in the catalogCarEntry list:
try
{
int accountNumber = int.Parse(values[(int)TextBoxIndices.Account]);
// Determine whether accountNumber is valid:
if (accountNumber > 0) // Maybe later add a check for correctness of the format of the 'balance field' too.
{
// Record containing TextBox values to output
var tempStorageRecord = new RecordSerializable(accountNumber,
values[(int)TextBoxIndices.First],
values[(int)TextBoxIndices.Last],
decimal.Parse(values[(int)TextBoxIndices.Balance]));
// Put that record as an element in its proper place within
// the catalogCarEntry list:
if (justModifyCurrentValue) // No maniplation of indexes or List elements necessary
{
if (catalogCarEntry.Count() >= 1) // Making sure the list is not empty.
{
catalogCarEntry[counter] = tempStorageRecord;
// Put a copy of that newly modified element and put it into a temporary record of type
// RecordSerializable:
currentRecord = catalogCarEntry[counter];
var currentvalues = new string[] {
currentRecord.Account.ToString(),
currentRecord.FirstName.ToString(),
currentRecord.LastName.ToString(),
currentRecord.Balance.ToString()
};
// Display the contents of the modified element in the text boxes:
SetTextBoxValues(currentvalues);
}
else
{
MessageBox.Show("List Is Empty! No Element to Modify", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
counter = 0; // counter put to zero by default. Actually there is no elemet in an empty list.
// Display empty text boxes:
ClearTextBoxes();
}
}
if (insertValueInCurrentLocation) // Here some maniplation of indexes or List-elements necessary
{
if (catalogCarEntry.Count() >= 1) // Making sure the list is not empty.
{
// Insert an element to the list 'catalogCarEntry' at the location specified
// by the current value of the counter:
catalogCarEntry.Insert(counter, tempStorageRecord);
// Put a copy of that newly inserted element and put it into a temporary record of type
// RecordSerializable:
currentRecord = catalogCarEntry[counter];
var insertedcurrentvalues = new string[] {
currentRecord.Account.ToString(),
currentRecord.FirstName.ToString(),
currentRecord.LastName.ToString(),
currentRecord.Balance.ToString()
};
// Display the contents of the inserted element in the text boxes:
SetTextBoxValues(insertedcurrentvalues);
}
else
{
// catalogCarEntry[0] = tempStorageRecord; // If the list is empty, it is transformed into one with one element.
catalogCarEntry.Add(tempStorageRecord);
// Put a copy of that newly inserted element and put it into a temporary record of type
// RecordSerializable:
currentRecord = catalogCarEntry[0];
var insertedcurrentvalues = new string[] {
currentRecord.Account.ToString(),
currentRecord.FirstName.ToString(),
currentRecord.LastName.ToString(),
currentRecord.Balance.ToString()
};
// Display the contents of the inserted element in the text boxes:
SetTextBoxValues(insertedcurrentvalues);
}
}
if (appendValueToEndOfList) // Here an element is added to the end of the list:
{
if (catalogCarEntry.Count() >= 1) // Making sure the list is not empty.
{
// Append an element to the list 'catalogCarEntry' at the very end:
// by the current value of the counter:
catalogCarEntry.Add(tempStorageRecord); // This appends the tempStorageRecord to the end of the list.
// Now display the newly appended element that is at the very end of the modified list:
// First get the index value of the last element which is the number of elements minus one.
// (Minus one because the indexes start at zero.)
counter = catalogCarEntry.Count() - 1;
// Put a copy of that newly appended element and put it into a temporary record of type
// RecordSerializable:
currentRecord = catalogCarEntry[counter];
// store RecordSerializable values in temporary string array
var appendedvalues = new string[] {
currentRecord.Account.ToString(),
currentRecord.FirstName.ToString(),
currentRecord.LastName.ToString(),
currentRecord.Balance.ToString()
};
// Display the contents of the appended element in the text boxes:
SetTextBoxValues(appendedvalues);
}
else
{
// catalogCarEntry.Add(tempStorageRecord); // If the list is empty, it is transformed into one with one element
// consisting of the newly added record.
// I think you get a one element list if you do this to an empty list.
// I think it has been assured here that here catalogCarEntry can't be anything but an empty List.
// Perhaps some extra test here would be advisable:
catalogCarEntry.Add(tempStorageRecord);
// Put a copy of that newly appended element and put it into a temporary record of type
// RecordSerializable:
currentRecord = catalogCarEntry[0];
var appendedvalues = new string[] {
currentRecord.Account.ToString(),
currentRecord.FirstName.ToString(),
currentRecord.LastName.ToString(),
currentRecord.Balance.ToString()
};
// Display the contents of the appended element in the text boxes:
SetTextBoxValues(appendedvalues);
}
}
}
else
{
// Notifying the user if the account number was invalid
MessageBox.Show("Invalid Account Number", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
// It can be mentioned here that I think catching serialization is not relevant here.
catch (FormatException)
{
MessageBox.Show("Invalid Format", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
// Return to the default settings of in terms of which buttons are enabled and not enabled:
step_down.Enabled = true;
step_up.Enabled = true;
add_element_current_location.Enabled = true;
add_element_end_of_list.Enabled = true;
initial_list_element.Enabled = true;
load_from_binary_file.Enabled = true;
save_to_binary_file.Enabled = true;
delete_current_element.Enabled = true;
modify_element.Enabled = true;
// Back to the default settings as regards for which of the 3 types of modifications to implement:
justModifyCurrentValue = true;
insertValueInCurrentLocation = false;
appendValueToEndOfList = false;
}
// Method for handing step up click:
private void step_up_Click(object sender, EventArgs e)
{
if (catalogCarEntry.Count() != 0) // Making sure the list is not empty.
{
// If list is not empty go up the list when possible:
if ((counter + 1) == catalogCarEntry.Count()) // Check if counter is currently on the last (highest) element
{ // of the list. Note that one needs to be added, because inexing
// starts at 0.
MessageBox.Show("Upper Bound of Catalog Reached", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
// The counter is not incremented. It remains in the value that it was in before entering the module.
}
else
{
counter = counter + 1;
}
currentRecord = catalogCarEntry[counter];
// store RecordSerializable values in temporary string array
var values = new string[] {
currentRecord.Account.ToString(),
currentRecord.FirstName.ToString(),
currentRecord.LastName.ToString(),
currentRecord.Balance.ToString()
};
// It can't be overemphasized how important it is to keep track of the current counter value
// as well as the overalall length of the list (the number of elements in it)
// in the entire program.
// determine whether TextBox account field is empty
if (!string.IsNullOrEmpty(values[(int)TextBoxIndices.Account])) // this seems also to check perhaps if
// list has no element at all, provided
// a conversion of an empty list of
// RecordSeriaizable elements gets
// transformed into a Null during
// the transformation to the string
// array above.
{
// store TextBox values in RecordSerializable and set to the
// text boxes, provided that everything is OK regarding format
// and account number:
try
{
// get account-number value from TextBox
int accountNumber = int.Parse(
values[(int)TextBoxIndices.Account]);
// determine whether accountNumber is valid
if (accountNumber > 0)
{
// copy string-array values to TextBox values
SetTextBoxValues(values);
}
else
{
// notify user if invalid account number
MessageBox.Show("Invalid Account Number", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
catch (FormatException)
{
MessageBox.Show("Invalid Format", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
else
{
MessageBox.Show("List is Empty!", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
// ClearTextBoxes(); // clear TextBox values. I don't think it is needed here.
}
}
// Method for handling step down click:
private void step_down_Click(object sender, EventArgs e)
{
if (catalogCarEntry.Count() != 0) // Making sure the list is not empty.
{
// lower counter by 1, when possible:
if (counter <= 0)
{
counter = 0;
MessageBox.Show("Lower Bound of Catalog Reached", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
else
{
counter = counter - 1;
}
currentRecord = catalogCarEntry[counter];
// store RecordSerializable values in temporary string array
var values = new string[] {
currentRecord.Account.ToString(),
currentRecord.FirstName.ToString(),
currentRecord.LastName.ToString(),
currentRecord.Balance.ToString()
};
// It can't be overemphasized how important it is to keep track of the current counter value
// as well as the overalall length of the list (the number of elements in it)
// in the entire program.
// determine whether TextBox account field is empty
if (!string.IsNullOrEmpty(values[(int)TextBoxIndices.Account])) // this seems also to check perhaps
// if list has not element, provided
// a conversion of an empty list of
// RecordSeriaizable elements gets
// transformed into a Null during
// the transformation to the string
// array above.
{
// Checking first format of account number is OK. If not format exception.
// If format is OK, then check if number is greater that 0. Eventually
// display contents of the RecordSerializable as strings in the
// corresponding text boxes:
try
{
// get account-number value from TextBox
int accountNumber = int.Parse(
values[(int)TextBoxIndices.Account]);
// determine whether accountNumber is valid
if (accountNumber > 0)
{
// copy string-array values to TextBox values
SetTextBoxValues(values);
}
else
{
// notify user if invalid account number
MessageBox.Show("Invalid Account Number", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
catch (FormatException)
{
MessageBox.Show("Invalid Format", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
else
{
MessageBox.Show("List is Empty!", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
}
// Method for handling loading of the form:
private void Form1_Load(object sender, EventArgs e)
{
// See to it that by default the first element of the list (element with index 0) gets displayed
// when the file is loaded.
// Should the list be empty there will be a corresponding error handling procedure.
// Note that the counter has been declared 0 at the very beginning of the program, so I won't be doing it
// again here.
if (catalogCarEntry.Count() != 0) // Making sure the list is not empty.
{
currentRecord = catalogCarEntry[counter];
// store RecordSerializable values in temporary string array
var values = new string[] {
currentRecord.Account.ToString(),
currentRecord.FirstName.ToString(),
currentRecord.LastName.ToString(),
currentRecord.Balance.ToString()
};
// It can't be overemphasized how important it is to keep track of the current counter value
// as well as the overalall length of the list (the number of elements in it)
// in the entire program.
// determine whether TextBox account field is empty
if (!string.IsNullOrEmpty(values[(int)TextBoxIndices.Account])) // this seems also to check perhaps
// if list has not element, provided
// a conversion of an empty list of
// RecordSeriaizable elements gets
// transformed into a Null during
// the transformation to the string
// array above.
{
// store TextBox values in RecordSerializable and setting to text
// box values, provided that everything is OK as regards for
// format and account number:
try
{
// get account-number value from TextBox
int accountNumber = int.Parse(
values[(int)TextBoxIndices.Account]);
// determine whether accountNumber is valid
if (accountNumber > 0)
{
// copy string-array values to TextBox values
SetTextBoxValues(values);
}
else
{
// notify user if invalid account number
MessageBox.Show("Invalid Account Number", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
catch (FormatException)
{
MessageBox.Show("Invalid Format", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
else
{
MessageBox.Show("List is Empty!", "Error",
MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
}
