Riley,
Sorry to be so late in replying. I hope this helps you ... it's a little something I had written up about a year ago for numeric TextBoxes.
This example has been subclassed from MyTextBox subclass and will need additional tweaking if you want to sub-class from the System.Windows.Forms.TextBox. In particular notice that all the eventhandlers are overridden from the parent class. But other than that minor tweaking, this should work just fine.
public class MyNumericTextBox : MyTextBox
{
#region Declarations
private int m_DecimalPlaces = 0;
private decimal m_Maximum = 100;
private decimal m_Minimum = 0;
protected char[] AllowedChars = {'1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '-'};
protected string m_FormatString = "##0";
private bool m_DisplayDefaultZero = true;
#endregion
#region Constructor
public MyNumericTextBox()
{
this.MaxLength = 3;
this.TextAlign = System.Windows.Forms.HorizontalAlignment.Right;
}
#endregion
#region Methods
public void SetText(object val)
{
if (this.m_Minimum > 0)
{
if (val is Decimal)
this.Text = ((decimal)val).ToString(this.m_FormatString);
}
else
{
if (val is int)
this.Text = ((int)val).ToString(this.m_FormatString);
}
}
#endregion
#region Events
protected override void FormatHandler(object sender, ConvertEventArgs e)
{
if(this.DisplayDefaultZero)
{
if (e.Value == System.DBNull.Value)
e.Value = (int)0;
}
if (e.Value is Decimal && e.DesiredType == typeof(string))
e.Value = ((decimal)e.Value).ToString(this.m_FormatString);
else if (e.Value is int && e.DesiredType == typeof(string))
e.Value = ((int)e.Value).ToString(this.m_FormatString);
}
protected override void ParseHandler(object sender, ConvertEventArgs e)
{
if (((string)e.Value).Trim().Length == 0)
e.Value = "0";
if (e.DesiredType == typeof(decimal))
e.Value = Decimal.Parse((string)e.Value, System.Globalization.NumberStyles.Any);
else if (e.DesiredType == typeof(int))
{
string[] s = ((string)e.Value).Trim().Split('.');
e.Value = Decimal.Parse(s[0], System.Globalization.NumberStyles.Any);
}
}
protected override void KeyPressHandler(object sender, KeyPressEventArgs e)
{
bool allowed = false;
for (int i = 0; i < this.AllowedChars.Length; i++)
{
if (e.KeyChar == this.AllowedChars[i])
{
allowed = true;
break;
}
}
if (allowed == true)
{
string CurrentText = this.Text;
if (this.SelectionLength > 0)
{
int i = this.Text.IndexOf(this.SelectedText);
int j = i + this.SelectionLength;
if (i > 0 && j == this.TextLength)
CurrentText = this.Text.Substring(0, i);
else
if (i > 0)
CurrentText = this.Text.Substring(0, i) + this.Text.Substring(j);
else
CurrentText = this.Text.Substring(j);
}
if (CurrentText != this.SelectedText)
{
if ((e.KeyChar == '.' || e.KeyChar == '-') &&
CurrentText.IndexOf(e.KeyChar) >= 0)
e.Handled = true;
else
{
if (this.m_DecimalPlaces > 0 &&
e.KeyChar != '.' && e.KeyChar != '-' && e.KeyChar != (char)Keys.Back)
{
int MaxDecimalPos = this.MaxLength - this.m_DecimalPlaces - 1;
int DecimalPos = CurrentText.IndexOf('.');
int DecimalDigits = CurrentText.Length - DecimalPos - 1;
if (DecimalPos < 0)
{
if (CurrentText.Length >= MaxDecimalPos)
e.Handled = true;
}
else
if (this.SelectionStart <= DecimalPos)
{
if (DecimalPos == MaxDecimalPos)
e.Handled = true;
}
else
if (this.SelectionStart >= CurrentText.Length)
{
if (DecimalDigits == this.m_DecimalPlaces)
e.Handled = true;
}
}
}
}
}
else
e.Handled = true;
}
protected override void ValidatingHandler(object sender, CancelEventArgs e)
{
if (this.Text.Trim().Length == 0)
return;
try
{
decimal test = Decimal.Parse(this.Text);
if (test > this.m_Maximum || test < this.m_Minimum)
{
string message = "The value for this field must be between " +
this.m_Maximum.ToString() + " and " + this.m_Minimum.ToString() + "!";
string caption = "Value out of range";
MessageBox.Show(message, caption, MessageBoxButtons.OK, MessageBoxIcon.Error);
e.Cancel = true;
}
}
catch (Exception ex)
{
System.Diagnostics.Debug.WriteLine(ex.Message);
}
}
#endregion
#region Properties
[Description("The number of digits to display after the decimal.")]
[DefaultValue(0)]
public int DecimalPlaces
{
get {return this.m_DecimalPlaces;}
set
{
this.m_DecimalPlaces = value;
if (value > 0 && this.m_Minimum < 0)
this.AllowedChars = new char[] {(char)Keys.Back, '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '.', '-'};
else if (value > 0)
this.AllowedChars = new char[] {(char)Keys.Back, '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '.'};
else if (this.m_Minimum < 0)
this.AllowedChars = new char[] {(char)Keys.Back, '1', '2', '3', '4', '5', '6', '7', '8', '9', '0', '-'};
else
this.AllowedChars = new char[] {(char)Keys.Back, '1', '2', '3', '4', '5', '6', '7', '8', '9', '0'};
string[] format = this.m_FormatString.Split(new char[] {'.'}, 2);
if (value > 0)
{
string s = new string('0', value);
this.m_FormatString = format[0] + "." + s;
}
else
this.m_FormatString = format[0];
this.MaxLength = this.m_FormatString.Length;
if (this.m_Minimum < 0 && this.m_Minimum.ToString().Length > this.m_Maximum.ToString().Length)
this.MaxLength++;
}
}
[Description("The maximum value allowed in the field.")]
[DefaultValue(100)]
public decimal Maximum
{
get {return this.m_Maximum;}
set
{
if (value < this.m_Minimum)
return;
this.m_Maximum = value;
this.MaxLength = value.ToString().Length;
int max = this.m_Minimum.ToString().Length;
if (this.m_Minimum < 0 && max > this.MaxLength)
this.MaxLength = max;
if (this.MaxLength > 2 && value.ToString().Length < this.m_Minimum.ToString().Length)
this.m_FormatString = new string('#', this.MaxLength - 2) + "0";
else if (this.MaxLength > 1)
this.m_FormatString = new string('#', this.MaxLength - 1) + "0";
else
this.m_FormatString = "0";
this.DecimalPlaces = this.m_DecimalPlaces;
}
}
[Description("The minimum value allowed in the field.")]
[DefaultValue(0)]
public decimal Minimum
{
get {return this.m_Minimum;}
set
{
if (value > this.m_Maximum)
return;
this.m_Minimum = value;
this.Maximum = this.m_Maximum;
}
}
[Description("Enable if you don't want to display a zero in this field")]
public bool DisplayDefaultZero
{
get {return this.m_DisplayDefaultZero;}
set {this.m_DisplayDefaultZero = value;}
}
#endregion
}~~Bonnie
>This should be so simple.
>
>I have maskedtextboxes on a form and I have set the input mask to 999.99 and I have the TextMaskFormat property set to IncludeLiterals.
>
>I am trying to set the display value of a field on the form to a calculated value from the other fields. I can make it work if I don't use maskedtextboxes but then the user can enter anyting not just numbers.
>
>The following code gives me the "Input String was not in a correct format."
>error.
>
>netamt = Convert.ToDecimal(this.mmTextgross.Text) -
> (Convert.ToDecimal(mmTextFtax.Text) +
> Convert.ToDecimal(this.mmTextStax.Text) +
> Convert.ToDecimal(this.mmTextMiscDed.Text));
>
>I can set the TextMaskFormat prop to exclude litterals and make it work but then if I enter 37.31 in one for the fields 3731 is stored in the db not 37.31
>
>Anyone have any ideas?
>
>Thanks
