currency.cs

一个掌上电脑PPC用的汇率转换软件

		{
			// Initialize list of all available currencies
			// *******************************************
			initializeAvailableCurrencies();

			// Create needed Data-Views based on DataSet
			// ******************************************
			initializeViews();

			// Read the offline rates store (xml) - if exists
			// **********************************************
			if (File.Exists(currencyXmlFile) == true)
			{
				try
				{
					ds.ReadXml(currencyXmlFile);
				}
				catch (SecurityException exception) 
				{
					MessageBox.Show(exception.Message, applicationError, MessageBoxButtons.OK, MessageBoxIcon.Hand, MessageBoxDefaultButton.Button1);
					this.Close();
				}

				if (ds.Tables[CURRENCY].Rows.Count > 0)
				{
					// Offline store is active and now looking for the base currency
					// *******************************************************************
					int indx = 0;
					foreach (DataRow row in ds.Tables[CURRENCY].Rows)
					{
						if (Convert.ToInt32(row[RATE]) == 1) // is there any candidate for the base currency?
						{
							textBoxBase.Text = row[SYMBOL].ToString();
							comboBoxFrom.SelectedItem = comboBoxFrom.Items[indx];
						}
						else if (Convert.ToInt32(row[RATE]) == 0) // Is there any irregular item?
						{
							// Uninitialized currency rate. Raise attention!
							// *********************************************
							raiseAttention(true);
						}
						indx++;
					}

					comboBoxTo.SelectedItem = comboBoxFrom.Items[0];
					tabControl1.SelectedIndex = 0;	// ready to use and switch to the main application page
				}
				else
					activateOptionsPage();
			}
			else
				activateOptionsPage();
		}

		#region PRIVATE_METHODS

		/// <summary>
		/// Just changes the tab-page index along with an informational message
		/// </summary>
		void activateOptionsPage()
		{
			tabControl1.SelectedIndex = 1; 
			MessageBox.Show(messageCreatePreferences, attentionInitialize, MessageBoxButtons.OK, MessageBoxIcon.Asterisk, MessageBoxDefaultButton.Button1);
		}

		/// <summary>
		/// Show a yellow icon and a label-message advising the user to update the list
		/// of preferences as new items arrived.
		/// </summary>
		/// <param name="activate">true to raise the attention, false for returning to the normal state</param>
		void raiseAttention(bool activate)
		{
			label2.Text = (activate) ? messageUpdatePreferences : messageMyPreferences;
			label2.ForeColor = (activate) ? Color.DarkCyan : SystemColors.ControlText; 
			this.pictureBoxWarning.Visible = activate;
		}

		/// <summary>
		/// Creating the list of all available currencies, sorting the list and creating indexes
		/// (using HashTabel) to find the items if requested. After finishing the basic tasks, the
		/// hosting ComboBox is filled with the available items.
		/// </summary>
		void initializeAvailableCurrencies()
		{
			ArrayList al = new ArrayList(164);
			ht = new Hashtable(164);

			Cursor.Current = Cursors.WaitCursor;	
			comboBoxCurr.Items.Clear();

			Type currency = typeof(WebServiceX.Currency);

			int key = 0;
			foreach(FieldInfo s in currency.GetFields())
			{
				string str = s.Name;
				if (str.Length == 3)
				{
					al.Add(str);		
					ht.Add(str, key);
					key++;
				}
			}

			al.Sort();
			for (int i = 0; i < al.Count; i++)
				comboBoxCurr.Items.Add(al[i]);

			comboBoxCurr.SelectedItem = comboBoxCurr.Items[0];
			comboBoxCurr.Refresh();
			Cursor.Current = Cursors.Default;	
		}

		/// <summary>
		/// On German Pocket PC istead of a "Personal" there is "Privat" folder available.
		/// YES - this is just a workaround and not a finished solution.
		/// </summary>
		private void checkPrivateFolders()
		{
			try
			{
				// Try EN and DE folders
				if (Directory.Exists(folderPersonal))
					currencyXmlFile = folderPersonal + "\\" + currencyStore;
				else if (Directory.Exists(folderPrivat))
					currencyXmlFile = folderPrivat + "\\" + currencyStore;
				else
				{	// Create a new one
					DirectoryInfo di = Directory.CreateDirectory(folderPersonal);
					currencyXmlFile = folderPersonal + "\\" + currencyStore;
				}
			}
			catch (IOException exception)
			{
				MessageBox.Show(exception.Message, "Exception", MessageBoxButtons.OK, MessageBoxIcon.Hand, MessageBoxDefaultButton.Button1);
				this.Close();
			}
			catch (UnauthorizedAccessException exception)
			{
				MessageBox.Show(exception.Message, "Exception", MessageBoxButtons.OK, MessageBoxIcon.Hand, MessageBoxDefaultButton.Button1);
				this.Close();
			}
		}

		/// <summary>
		/// Creating data views based on the DataSet instance
		/// </summary>
		private void initializeViews()
		{
			viewFrom = new DataView(ds.Tables[CURRENCY]);
			viewTo = new DataView(ds.Tables[CURRENCY]);
			viewBox = new DataView(ds.Tables[CURRENCY]);

			comboBoxFrom.Items.Clear();
			comboBoxFrom.DataSource = viewFrom;
			comboBoxFrom.DisplayMember = SYMBOL;
			comboBoxFrom.ValueMember = RATE;

			comboBoxTo.Items.Clear();
			comboBoxTo.DataSource = viewTo;
			comboBoxTo.DisplayMember = SYMBOL;
			comboBoxTo.ValueMember = RATE;

			listBoxCurr.Items.Clear();
			listBoxCurr.DataSource = viewBox;
			listBoxCurr.DisplayMember = SYMBOL;
			listBoxCurr.ValueMember = RATE;
		}

		/// <summary>
		/// Converts the currencies from the available string representation to the standard integer based enumeration.
		/// </summary>
		/// <param name="symbol">The symbol as three character string</param>
		/// <returns>The rquested enumeration</returns>
		private WebServiceX.Currency getCurrency (string symbol)
		{
			int i = 0;
			if (ht.Contains(symbol))
				i = (int)ht[symbol];

			return (WebServiceX.Currency)i;
		}

		#endregion PRIVATE_METHODS

		private void buttonSave_Click(object sender, System.EventArgs e)
		{
			bool accessWebService = false;
			if (textBoxBase.Text.Length == 0)
			{
				MessageBox.Show(messageBaseCurrency, baseNotSet, MessageBoxButtons.OK, MessageBoxIcon.Asterisk, MessageBoxDefaultButton.Button1);
				return;
			}

			if (checkBoxWS.Checked == false)
			{
				DialogResult dialogResult = MessageBox.Show(checkCheckBoxWS, unavailableWS, MessageBoxButtons.YesNoCancel, MessageBoxIcon.Question, MessageBoxDefaultButton.Button1);
				if (dialogResult == DialogResult.Cancel)
					return;
				else if (dialogResult == DialogResult.Yes)
				{
					checkBoxWS.Checked = true;
					accessWebService = true;
				}
			}
			else
				accessWebService = true;

			Cursor.Current = Cursors.WaitCursor;
			try
			{
				WebServiceX.CurrencyConvertor ws = new WebServiceX.CurrencyConvertor();
				foreach (DataRow row1 in ds.Tables[CURRENCY].Rows)
				{
					if (row1[SYMBOL].ToString() == textBoxBase.Text)
						row1[RATE] = 1;
					else
					{
						if (accessWebService == true)
							row1[RATE] = ws.ConversionRate(getCurrency(textBoxBase.Text), getCurrency(row1[SYMBOL].ToString()));
						// otherwise is rate just left or for the new one is set to 0
					}
				}
				ds.WriteXml(currencyXmlFile);
				raiseAttention(!accessWebService);
			}
			catch (WebException)
			{
				MessageBox.Show(messageCheckNetwork, unavailableWS, MessageBoxButtons.OK, MessageBoxIcon.Hand, MessageBoxDefaultButton.Button1);
			}
			catch (IOException exception)
			{
				MessageBox.Show(exception.Message, fileError, MessageBoxButtons.OK, MessageBoxIcon.Hand, MessageBoxDefaultButton.Button1);
			}
			catch (SecurityException exception)
			{
				MessageBox.Show(exception.Message, applicationError, MessageBoxButtons.OK, MessageBoxIcon.Hand, MessageBoxDefaultButton.Button1);
				this.Close();
			}
			Cursor.Current = Cursors.Default;
		}

		private void buttonBase_Click(object sender, System.EventArgs e)
		{
			if (textBoxBase.Text.Length > 0 && listBoxCurr.Text.Length > 0)
			{
				// Old base exists, New exists -> thus list should be updated
				raiseAttention(true);
			}
			textBoxBase.Text = listBoxCurr.Text;
		}

		private void tabControl1_SelectedIndexChanged(object sender, System.EventArgs e)
		{
			switch (tabControl1.SelectedIndex)
			{
				case 0:
					inputPanel1.Enabled = true;
					textBoxValue.Focus();
					break;
				case 1:
					inputPanel1.Enabled = false;
					break;
				default: // Wonder - should never come here!
					break;
			}
		}

		private void buttonConvert_Click(object sender, System.EventArgs e)
		{
			if (textBoxValue.Text.Length > 0)
			{
				double from = 0;
				
				try
				{
					from = Convert.ToDouble(textBoxValue.Text);
				}
				catch (FormatException)
				{
					MessageBox.Show(messageCheckYourInput, wrongFormat, MessageBoxButtons.OK, MessageBoxIcon.Exclamation, MessageBoxDefaultButton.Button1);
					textBoxValue.SelectAll();
					return;
				}
				catch (OverflowException exception)
				{
					MessageBox.Show(exception.Message, wrongFormat, MessageBoxButtons.OK, MessageBoxIcon.Exclamation, MessageBoxDefaultButton.Button1);
					textBoxValue.SelectAll();
					return;
				}

				double fromCurrency = 1;	//= (double)comboBoxFrom.SelectedValue;
				double toCurrency = 0;		// = (double)comboBoxTo.SelectedValue;
				double result;
 
				if (checkBoxOff.Checked == true)
				{
					fromCurrency = (double)comboBoxFrom.SelectedValue;
					toCurrency = (double)comboBoxTo.SelectedValue;
				}
				else
				{
					// go online
					Cursor.Current = Cursors.WaitCursor;
					try
					{
						int indxFrom = comboBoxFrom.SelectedIndex;
						int indxTo = comboBoxTo.SelectedIndex;
						WebServiceX.CurrencyConvertor ws = new WebServiceX.CurrencyConvertor();

						if (comboBoxFrom.Text == textBoxBase.Text)
							fromCurrency = 1;
						else
							fromCurrency = ws.ConversionRate(getCurrency(textBoxBase.Text), getCurrency(comboBoxFrom.Text));
					
						if (comboBoxTo.Text == textBoxBase.Text)
							toCurrency = 1;
						else
							toCurrency = ws.ConversionRate(getCurrency(textBoxBase.Text), getCurrency(comboBoxTo.Text));

						// actualize
						comboBoxTo.SelectedValue = toCurrency;
						comboBoxTo.SelectedIndex = indxTo;

						comboBoxFrom.SelectedValue = fromCurrency;
						comboBoxFrom.SelectedIndex = indxFrom;

						// save changes
						ds.WriteXml(currencyXmlFile);
					}
					catch (WebException)
					{
						MessageBox.Show(messageCheckNetwork, unavailableWS, MessageBoxButtons.OK, MessageBoxIcon.Exclamation, MessageBoxDefaultButton.Button1);
					}
					catch (IOException exception)
					{
						MessageBox.Show(exception.Message, fileError, MessageBoxButtons.OK, MessageBoxIcon.Hand, MessageBoxDefaultButton.Button1);
					}
					catch (SecurityException exception)
					{
						MessageBox.Show(exception.Message, applicationError, MessageBoxButtons.OK, MessageBoxIcon.Hand, MessageBoxDefaultButton.Button1);
					}
					Cursor.Current = Cursors.Default;
				}

				result = from*(1/fromCurrency)*toCurrency;
				textBoxResult.Text = Math.Round(result, 2).ToString();
			}
			textBoxValue.Focus();
		}

		private void buttonRemove_Click(object sender, System.EventArgs e)
		{
			if (textBoxBase.Text == listBoxCurr.Text)
			{
				textBoxBase.Text = "";
				MessageBox.Show(messageBaseDeleted, baseDeleted, MessageBoxButtons.OK, MessageBoxIcon.Asterisk, MessageBoxDefaultButton.Button1);
			}
			ds.Tables[CURRENCY].Rows.RemoveAt(listBoxCurr.SelectedIndex);
		}

		private void inputPanel1_EnabledChanged(object sender, System.EventArgs e)
		{
			int absoluteHeight = this.Bounds.Height;
			tabControl1.Height = (inputPanel1.Enabled) ? absoluteHeight - inputPanel1.Bounds.Height : absoluteHeight;
			//tabControl1.Height = (inputPanel1.Enabled) ? 272 - inputPanel1.Bounds.Height : 272;
		}

		private void comboBoxTo_SelectedValueChanged(object sender, System.EventArgs e)
		{
			if (tabControl1.SelectedIndex == 0)
				textBoxValue.Focus();
		}

		private void tabControl1_GotFocus(object sender, System.EventArgs e)
		{
			if (tabControl1.SelectedIndex == 0)
			{
				inputPanel1.Enabled = true;
				textBoxValue.Focus();
			}
		}

		private void Form1_GotFocus(object sender, System.EventArgs e)
		{
			if (tabControl1.SelectedIndex == 0)
			{
				inputPanel1.Enabled = true;
				textBoxValue.Focus();
			}
			else
				inputPanel1.Enabled = false;
		}

		/// <summary>
		/// The combo-box with all available currencies on Option-Page got focus
		/// </summary>
		/// <param name="sender"></param>
		/// <param name="e"></param>
		private void comboBoxCurr_GotFocus(object sender, System.EventArgs e)
		{
			inputPanel1.Enabled = true;
		}

		private void buttonClear_Click(object sender, System.EventArgs e)
		{
			textBoxValue.Text = "";
			textBoxResult.Text = "";
			inputPanel1.Enabled = true;
			textBoxValue.Focus();
		}
	}
}