Windows Controls: The Time Picker

Introduction to the Time Picker

Description

The time picker is a control that allows the user to select a time value:

One of the advantages of the time Picker control is that it allows the user to select a time value instead of typing it. This tremendously reduces the likelihood of mistakes.

Creating a Date/Time Picker

To create a time picker, add a DateTimePicker control to a form or other container. The DateTimePicker control is based on the DateTimePicker class. In reality, the DateTimePicker control can be considered as two controls in one: you just have to choose which one of both controls you want to use.

Introduction to the Time Picker

Overview

As described already, the date time picker is two controls in one object. To transform a date time picker into a time picker control, change its Format property to a Time value:

using System;
using System.Drawing;
using System.Windows.Forms;

public class Exercise : System.Windows.Forms.Form
{
    DateTimePicker dtpTimeArrived;

    public Exercise()
    {
        InitializeComponent();
    }

    void InitializeComponent()
    {
        dtpTimeArrived = new DateTimePicker();
        dtpTimeArrived.Location = new Point(12, 12);
        dtpTimeArrived.Format = DateTimePickerFormat.Time;

        Controls.Add(dtpTimeArrived);
        Text = "Time Picker";
    }
}

public class Program
{
    static int Main()
    {
        System.Windows.Forms.Application.Run(new Exercise());
        return 0;
    }
}

Although optional, you should (with emphasis) also set the ShowUpDown Boolean property to True:

 void InitializeComponent()
{
    dtpTimeArrived = new DateTimePicker();
    dtpTimeArrived.Location = new Point(12, 12);
    dtpTimeArrived.ShowUpDown = true;
    dtpTimeArrived.Format = DateTimePickerFormat.Time;
}

This makes it a true time picker control:

If you do not set the ShowUpDown property to true, the control would display as a combo box and when the user clicks the arrow button, a calendar would come, which does not make sense since the purpose of the control is to deal with time values.

Practical Learning: Introducing the Date Picker

1. Start a new Windows Application named GeorgetownCleaningServices2
2. Design the form as follows:
    

   

   Control		Name	Text	Additional Properties
   GroupBox			Order Identification
   Label			Customer Name:
   TextBox		txtCustomerName
   Label			Customer Phone:
   TextBox		txtCustomerPhone
   Label			Date Left:
   DateTimePicker		dtpDateLeft
   Label			Time Left:
   DateTimePicker		dtpTimeLeft		Format: Time
   Label			Date Expected:
   DateTimePicker		dtpDateExpected
   Label			Time Expected:
   DateTimePicker		dtpTimeExpected		Format: Time
   GroupBox			Order Processing
   Label			Item Type
   Label			Unit Price
   Label			Qty
   Label			Sub Total
   Label			Shirts
   TextBox		txtShirtsUnitPrice	1.25	TextAlign: Right
   TextBox		txtShirtsQuantity	0	TextAlign: Right
   TextBox		txtShirtsSubTotal	0.00	TextAlign: Right
   Label			Pants
   TextBox		txtPantsUnitPrice	1.95	TextAlign: Right
   TextBox		txtPantsQuantity		TextAlign: Right
   TextBox		txtPantsSubTotal	0.00	TextAlign: Right
   ComboBox		cbxItem1	None	Items: None Women Suit Dress Regular Skirt Skirt With Hook Men's Suit 2Pc Men's Suit 3Pc Sweaters Silk Shirt Tie Coat Jacket Swede
   TextBox		txtItem1UnitPrice	0.00	TextAlign: Right
   TextBox		txtItem1Quantity	0	TextAlign: Right
   TextBox		txtItem1SubTotal	0.00	TextAlign: Right
   ComboBox		cbxItem2	None	Items: None Women Suit Dress Regular Skirt Skirt With Hook Men's Suit 2Pc Men's Suit 3Pc Sweaters Silk Shirt Tie Coat Jacket Swede
   TextBox		txtItem2UnitPrice	0.00	TextAlign: Right
   TextBox		txtItem2Quantity	0	TextAlign: Right
   TextBox		txtItem2SubTotal	0.00	TextAlign: Right
   ComboBox		cbxItem3	None	Items: None Women Suit Dress Regular Skirt Skirt With Hook Men's Suit 2Pc Men's Suit 3Pc Sweaters Silk Shirt Tie Coat Jacket Swede
   TextBox		txtItem3UnitPrice	0.00	TextAlign: Right
   TextBox		txtItem3Quantity	0	TextAlign: Right
   TextBox		txtItem3SubTotal	0.00	TextAlign: Right
   ComboBox		cbxItem4	None	Items: None Women Suit Dress Regular Skirt Skirt With Hook Men's Suit 2Pc Men's Suit 3Pc Sweaters Silk Shirt Tie Coat Jacket Swede
   TextBox		txtItem4UnitPrice	0.00	TextAlign: Right
   TextBox		txtItem4Quantity	0	TextAlign: Right
   TextBox		txtItem4SubTotal	0.00	TextAlign: Right
   GroupBox			Order Summary
   Button		btnCalculate	Calculate
   Label			Cleaning Total:
   TextBox		txtCleaningTotal	0.00	TextAlign: Right
   Label			Tax Rate:
   TextBox		txtTaxRate	7.75	TextAlign: Right
   Label			%
   Label			Tax Amount:
   TextBox		txtTaxAmount	0.00	TextAlign: Right
   Label			Net Total:
   TextBox		txtNetPrice	0.00	TextAlign: Right
   Button		btnClose	Close

3. Save the form

Using the Time Picker

The time picker is meant either to only display a time to the user or to both display time and allow the user to specify a time. The control follows the format of the time values set in the regional settings of Control Panel. By default, in US English, the time is divided in four sections that include the hour value, the minute value, the second value, and the AM/PM side. These sections are separated by standard characters that also are specified in the regional settings of Control Panel.

To change the time, the user can click a section, such as the hour, the minute, the second, or the AP/PM side, then click one of the arrows of the spin button. The up button increases (only) the value of the selected section while the down button decreases (only) the value of the selected section. The user can also use the arrow keys to change the value of a section.

After changing the value of the time, even the change occurs for only one section, the control fires a ValueChanged event, which is the default event of the control. Here is an example of using it:

using System;
using System.Drawing;
using System.Windows.Forms;

public class Exercise : System.Windows.Forms.Form
{
    DateTimePicker dtpTimeArrived;

    public Exercise()
    {
        InitializeComponent();
    }

    void InitializeComponent()
    {
        dtpTimeArrived = new DateTimePicker();
        dtpTimeArrived.Location = new Point(12, 12);
        dtpTimeArrived.ShowUpDown = true;
        dtpTimeArrived.Format = DateTimePickerFormat.Time;
        dtpTimeArrived.ValueChanged += new EventHandler(dtpTimeArrivedValueChanged);

        Controls.Add(dtpTimeArrived);
        Text = "Date Time Picker Example";
    }

    void dtpTimeArrivedValueChanged(object sender, EventArgs e)
    {

    }
}

public class Program
{
    static int Main()
    {
        System.Windows.Forms.Application.Run(new Exercise());
        return 0;
    }
}

Characteristics of the Time Picker

The Value of the Time Picker

As mentioned already, the user changes the time by using the various sections of the control. If the user changes the value of a section, it is considered that the whole time has been changed. At any time, the (current) time of the control is stored in the Value property. You can use this property either to programmatically change the time on the control or to get the time on the control.

Here is an example of using it:

void dtpTimeArrivedValueChanged(object sender, EventArgs e)
{
    MessageBox.Show("Time Arrived: " + dtpTimeArrived.Value.ToShortTimeString());
}

Application: Using the Time Picker

1. On the form, double-click the Time Left control and implement its ValueChanged event as follows:

   private void dtpTimeLeft_ValueChanged(object sender, EventArgs e)
   {
       DateTime dateLeft = this.dtpDateLeft.Value;
       DateTime timeLeft = this.dtpTimeLeft.Value;
   
       DateTime time9AM = new DateTime(timeLeft.Year, timeLeft.Month, timeLeft.Day, 9, 0, 0);
   
       // If the customer leaves clothes before 9AM...
       if (timeLeft <= time9AM)
       {
           // ... then they should be ready the same day after 5PM
           this.dtpDateExpected.Value = dateLeft;
           this.dtpTimeExpected.Value = new DateTime(dateLeft.Year, dateLeft.Month, dateLeft.Day, 17, 0, 0);
       }
       else
       {
           // If the clothes were left after 9AM, they will be available the following morning at 8AM
           this.dtpDateExpected.Value = new DateTime(dateLeft.Year, dateLeft.Month, dateLeft.Day + 1);
           this.dtpTimeExpected.Value = new DateTime(dateLeft.Year, dateLeft.Month, dateLeft.Day + 1, 8, 0, 0);
       }
   }

2. Return to the form and double-click the Calculate button
3. Implement its event as follows:

   private void btnCalculate_Click(object sender, EventArgs e)
   {
               decimal unitPriceShirts = 0.00M, unitPricePants = 0.00M,
                       unitPriceItem1 = 0.00M, unitPriceItem2 = 0.00M,
                       unitPriceItem3 = 0.00M, unitPriceItem4 = 0.00M;
               decimal subTotalShirts = 0.00M, subTotalPants = 0.00M,
                       subTotalItem1 = 0.00M, subTotalItem2 = 0.00M,
                       subTotalItem3 = 0.00M, subTotalItem4 = 0.00M;
               int qtyShirts = 1, qtyPants = 1, qtyItem1 = 1,
                   qtyItem2 = 1, qtyItem3 = 1, qtyItem4 = 4;
               decimal cleaningTotal = 0.00M, taxRate = 0.00M,
                       taxAmount = 0.00M, netPrice = 0.00M;
   
               // Retrieve the unit price of this item
               // Just in case the user types an invalid value, we are using a try...catch
               try
               {
                   unitPriceShirts = decimal.Parse(this.txtUnitPriceShirts.Text);
               }
               catch (FormatException)
               {
                   MessageBox.Show("The value you entered for the price of shirts is not valid" +
                                   "\nPlease try again");
                   return;
               }
   
               // Retrieve the number of this item
               // Just in case the user types an invalid value, we are using a try...catch
               try
               {
                   qtyShirts = int.Parse(this.txtQuantityShirts.Text);
               }
               catch (FormatException)
               {
                   MessageBox.Show("The value you entered for the number of shirts is not valid" +
                                   "\nPlease try again");
                   return;
               }
               try
               {
                   unitPricePants = decimal.Parse(this.txtUnitPricePants.Text);
               }
               catch (FormatException)
               {
                   MessageBox.Show("The value you entered for the price of pants is not valid" +
                                   "\nPlease try again");
                   return;
               }
   
               try
               {
                   qtyPants = int.Parse(this.txtQuantityPants.Text);
               }
               catch (FormatException)
               {
                   MessageBox.Show("The value you entered for the number of pants is not valid" +
                                   "\nPlease try again");
                   return;
               }
   
               if ((cbxItem1.Text == "None") || (cbxItem1.Text == ""))
               {
                   qtyItem1 = 0;
                   unitPriceItem1 = 0.00M;
               }
               else
               {
                   try
                   {
                       unitPriceItem1 = decimal.Parse(this.txtUnitPriceItem1.Text);
                   }
                   catch (FormatException)
                   {
                       MessageBox.Show("The value you entered for the price is not valid" +
                                   "\nPlease try again");
                       return;
                   }
               
                   try
                   {
                       qtyItem1 = int.Parse(this.txtQuantityItem1.Text);
                   }
                   catch (FormatException)
                   {
                       MessageBox.Show("The value you entered is not valid" +
                               "\nPlease try again");
                       return;
                   }
               }
   
               if ((cbxItem2.Text == "None") || (cbxItem2.Text == ""))
               {
                   qtyItem2 = 0;
                   unitPriceItem2 = 0.00M;
               }
               else
               {
                   try
                   {
                       unitPriceItem2 = decimal.Parse(this.txtUnitPriceItem2.Text);
                   }
                   catch (FormatException)
                   {
                       MessageBox.Show("The value you entered for the price is not valid" +
                               "\nPlease try again");
                       return;
                   }
                   try
                   {
                       qtyItem2 = int.Parse(this.txtQuantityItem2.Text);
                   }
                   catch (FormatException)
                   {
                       MessageBox.Show("The value you entered is not valid" +
                               "\nPlease try again");
                       return;
                   }
               }
   
               if ((cbxItem3.Text == "None") || (cbxItem3.Text == ""))
               {
                   qtyItem3 = 0;
                   unitPriceItem3 = 0.00M;
               }
               else
               {
                   try
                   {
                       unitPriceItem3 = decimal.Parse(this.txtUnitPriceItem3.Text);
                   }
                   catch (FormatException)
                   {
                       MessageBox.Show("The value you entered for the price is not valid" +
                               "\nPlease try again");
                       return;
                   }
                   try
                   {
                       qtyItem3 = int.Parse(this.txtQuantityItem3.Text);
                   }
                   catch (FormatException)
                   {
                       MessageBox.Show("The value you entered is not valid" +
                               "\nPlease try again");
                       return;
                   }
               }
   
               if ((cbxItem4.Text == "None") || (cbxItem4.Text == ""))
               {
                   qtyItem4 = 0;
                   unitPriceItem4 = 0.00M;
               }
               else
               {
                   try
                   {
                       unitPriceItem4 = decimal.Parse(this.txtUnitPriceItem4.Text);
                   }
                   catch (FormatException)
                   {
                       MessageBox.Show("The value you entered for the price is not valid" +
                               "\nPlease try again");
                       return;
                   }
                   try
                   {
                       qtyItem4 = int.Parse(this.txtQuantityItem4.Text);
                   }
                   catch (FormatException)
                   {
                       MessageBox.Show("The value you entered is not valid" +
                               "\nPlease try again");
                       return;
                   }
               }
   
               // Calculate the sub-total for this item
               subTotalShirts = qtyShirts * unitPriceShirts;
               subTotalPants = qtyPants * unitPricePants;
               subTotalItem1 = qtyItem1 * unitPriceItem1;
               subTotalItem2 = qtyItem2 * unitPriceItem2;
               subTotalItem3 = qtyItem3 * unitPriceItem3;
               subTotalItem4 = qtyItem4 * unitPriceItem4;
   
               // Calculate the total based on sub-totals
               cleaningTotal = subTotalShirts + subTotalPants + subTotalItem1 +
                       subTotalItem2 + subTotalItem3 + subTotalItem4;
   
               taxRate = decimal.Parse(this.txtTaxRate.Text);
               // Calculate the amount owed for the taxes
               taxAmount = cleaningTotal * taxRate / 100;
               // Add the tax amount to the total order
               netPrice = cleaningTotal + taxAmount;
   
               // Display the sub-total in the corresponding text box
               txtSubTotalShirts.Text = subTotalShirts.ToString("F");
               txtSubTotalPants.Text = subTotalPants.ToString("F");
               txtSubTotalItem1.Text = subTotalItem1.ToString("F");
               txtSubTotalItem2.Text = subTotalItem2.ToString("F");
               txtSubTotalItem3.Text = subTotalItem3.ToString("F");
               txtSubTotalItem4.Text = subTotalItem4.ToString("F");
   
               txtCleaningTotal.Text = cleaningTotal.ToString("F");
               txtTaxAmount.Text = taxAmount.ToString("F");
               txtNetPrice.Text = netPrice.ToString("F");	
   }

4. Return to the form
5. Double-click the Close button and implement its Click event as follows:
   

   private void btnClose_Click(object sender, EventArgs e)
   {
   	Close();
   }

6. Execute the application and create a few orders
    
   
7. Close the form and return to your programming environment

Using a Custom Format

By default, the time displays using the H:M:SS AM/PM format. This means that the time uses 1 digit for the hours from 0 to 9, 1 digit for the minutes from 0 to 9, 1 digit for the seconds from 0 to 9 and the AM or PM for morning or afternoon. To customize the way the time displays, first set the Format property to Custom. Then, in the CustomFormat property, use a combination of the following characters to create a custom format:

You can set the format at design time using the Format field on the Properties window. To set the format at run time, assign the desired format to the DateTimePicker.CustomFormat property.

By default, after adding the control to the form or container, it assumes the time of the computer when the control was added. If you want to set a different time, apply a Format combination to the Value property. Here is an example:

using System;
using System.Drawing;
using System.Windows.Forms;

public class Exercise : System.Windows.Forms.Form
{
    DateTimePicker dtpTimeArrived;

    public Exercise()
    {
        InitializeComponent();
    }

    void InitializeComponent()
    {
        dtpTimeArrived = new DateTimePicker();
        dtpTimeArrived.Location = new Point(40, 12);
        dtpTimeArrived.ShowUpDown = true;
        dtpTimeArrived.Format = DateTimePickerFormat.Custom;
        dtpTimeArrived.CustomFormat = "hh:mm tt";

        Controls.Add(dtpTimeArrived);
        Text = "Time Picker Example";
    }
}

public class Program
{
    static int Main()
    {
        System.Windows.Forms.Application.Run(new Exercise());
        return 0;
    }
}

In the same way, at any time, you can retrieve the time value on the control by accessing the Value property.