OpenHardwareMonitor: External/Aga.Controls/NumericTextBox.cs@090259cfd699

     1 using System;

     2 using System.ComponentModel;

     3 using System.Windows.Forms;

     4 using System.Globalization;

     7 namespace Aga.Controls

8 {

     9 	/// <summary>

    10 	/// Restricts the entry of characters to digits, the negative sign,

    11 	/// the decimal point, and editing keystrokes (backspace).

    12 	/// It does not handle the AltGr key so any keys that can be created in any

    13 	/// combination with AltGr these are not filtered

    14 	/// </summary>

    15 	public class NumericTextBox : TextBox

    16 	{

    17 		private const int WM_PASTE = 0x302;

    18 		private NumberStyles numberStyle = NumberStyles.AllowDecimalPoint | NumberStyles.AllowLeadingSign;

    20 		/// <summary>

    21 		/// Restricts the entry of characters to digits, the negative sign,

    22 		/// the decimal point, and editing keystrokes (backspace).

    23 		/// It does not handle the AltGr key

    24 		/// </summary>

    25 		/// <param name="e"></param>

    26 		protected override void OnKeyPress(KeyPressEventArgs e)

    27 		{

    28 			base.OnKeyPress(e);

    30 			e.Handled = invalidNumeric(e.KeyChar);

    31 		}

    34 		/// <summary>

    35 		/// Main method for verifying allowed keypresses.

    36 		/// This does not catch cut paste copy ... operations.

    37 		/// </summary>

    38 		/// <param name="key"></param>

    39 		/// <returns></returns>

    40 		private bool invalidNumeric(char key)

    41 		{

    42 			bool handled = false;

    44 			NumberFormatInfo numberFormatInfo = CultureInfo.CurrentCulture.NumberFormat;

    45 			string decimalSeparator = numberFormatInfo.NumberDecimalSeparator;

    46 			string negativeSign = numberFormatInfo.NegativeSign;

    48 			string keyString = key.ToString();

    50 			if (Char.IsDigit(key))

    51 			{

    52 				// Digits are OK

    53 			}

    54 			else if (AllowDecimalSeparator && keyString.Equals(decimalSeparator))

    55 			{

    56 				if (Text.IndexOf(decimalSeparator) >= 0)

    57 				{

    58 					handled = true;

    59 				}

    60 			}

    61 			else if (AllowNegativeSign && keyString.Equals(negativeSign))

    62 			{

    63 				if (Text.IndexOf(negativeSign) >= 0)

    64 				{

    65 					handled = true;

    66 				}

    67 			}

    68 			else if (key == '\b')

    69 			{

    70 				// Backspace key is OK

    71 			}

    72 			else if ((ModifierKeys & (Keys.Control)) != 0)

    73 			{

    74 				// Let the edit control handle control and alt key combinations

    75 			}

    76 			else

    77 			{

    78 				// Swallow this invalid key and beep

    79 				handled = true;

    80 			}

    81 			return handled;

    82 		}

    85 		/// <summary>

    86 		/// Method invoked when Windows sends a message.

    87 		/// </summary>

    88 		/// <param name="m">Message from Windows.</param>

    89 		/// <remarks>

    90 		/// This is over-ridden so that the user can not use

    91 		/// cut or paste operations to bypass the TextChanging event.

    92 		/// This catches ContextMenu Paste, Shift+Insert, Ctrl+V,

    93 		/// While it is generally frowned upon to override WndProc, no

    94 		/// other simple mechanism was apparent to simultaneously and

    95 		/// transparently intercept so many different operations.

    96 		/// </remarks>

    97 		protected override void WndProc(ref Message m)

    98 		{

    99 			// Switch to handle message...

   100 			switch (m.Msg)

   101 			{

   102 				case WM_PASTE:

   103 					{

   104 						// Get clipboard object to paste

   105 						IDataObject clipboardData = Clipboard.GetDataObject();

   107 						// Get text from clipboard data

   108 						string pasteText = (string)clipboardData.GetData(

   109 								DataFormats.UnicodeText);

   111 						// Get the number of characters to replace

   112 						int selectionLength = SelectionLength;

   114 						// If no replacement or insertion, we are done

   115 						if (pasteText.Length == 0)

   116 						{

   117 							break;

   118 						}

   119 						else if (selectionLength != 0)

   120 						{

   121 							base.Text = base.Text.Remove(SelectionStart, selectionLength);

   122 						}

   124 						bool containsInvalidChars = false;

   125 						foreach (char c in pasteText)

   126 						{

   127 							if (containsInvalidChars)

   128 							{

   129 								break;

   130 							}

   131 							else if (invalidNumeric(c))

   132 							{

   133 								containsInvalidChars = true;

   134 							}

   135 						}

   137 						if (!containsInvalidChars)

   138 						{

   139 							base.Text = base.Text.Insert(SelectionStart, pasteText);

   140 						}

   142 						return;

   143 					}

   145 			}

   146 			base.WndProc(ref m);

   147 		}

   150 		public int IntValue

   151 		{

   152 			get

   153 			{

   154 				int intValue;

   155 				Int32.TryParse(this.Text, numberStyle, CultureInfo.CurrentCulture.NumberFormat, out intValue);

   156 				return intValue;

   157 			}

   158 		}

   160 		public decimal DecimalValue

   161 		{

   162 			get

   163 			{

   164 				decimal decimalValue;

   165 				Decimal.TryParse(this.Text, numberStyle, CultureInfo.CurrentCulture.NumberFormat, out decimalValue);

   166 				return decimalValue;

   167 			}

   168 		}

   171 		private bool allowNegativeSign;

   172 		[DefaultValue(true)]

   173 		public bool AllowNegativeSign

   174 		{

   175 			get { return allowNegativeSign; }

   176 			set { allowNegativeSign = value; }

   177 		}

   179 		private bool allowDecimalSeparator;

   180 		[DefaultValue(true)]

   181 		public bool AllowDecimalSeparator

   182 		{

   183 			get { return allowDecimalSeparator; }

   184 			set { allowDecimalSeparator = value; }

   185 		}

   187 	}

   189 }

author	StephaneLenclud
	Sun, 03 Feb 2013 18:01:50 +0100
branch	MiniDisplay
changeset 433	090259cfd699
permissions	-rw-r--r--