void txtTradeInAllowance_Validating(object sender, CancelEventArgs e)
{
//declare a errorMessage string and set it's default value to empty string
string errorMessage = string.Empty;
//invoke the IsNumber in the AutomotiveManager class to check if the text of TradeInAllowance could be parse to a number
if (!AutomotiveManager.IsNumber(txtTradeInAllowance.Text))
{
//set error message
errorMessage = "Please enter a numeric value.";
}
//parse the text of the TradeInAllowance textbox to decimal and check if it less than 0
else if (Decimal.Parse(txtTradeInAllowance.Text) < 0)
{
//set error message
errorMessage = "Please enter a value greater than or equal to zero.";
}
//check if the errorMessage is not an empty string
if (!errorMessage.Equals(string.Empty))
{
//set the CancelEventArgs' Cancel property to true
e.Cancel = true;
//invoke SetError method in errorProvider control and set the errorMessage to TradeInAllowance textbox
errorProvider.SetError(txtTradeInAllowance, errorMessage);
//set focus to TradeInAllowance textbox
txtTradeInAllowance.Focus();
}
}
/// <summary>
/// the event handler to check if the value of textbox is a numeric value
/// </summary>
void txtNumeric_Validating(object sender, CancelEventArgs e)
{
if (!AutomotiveManager.IsNumber(((TextBox)sender).Text.Trim()))
{
// Prevents the validated event from being triggered
e.Cancel = true;
if (!_errorFocus)
{
((TextBox)sender).Focus();
_errorFocus = true;
}
// Show the error icon beside the control
errorProvider.SetError(((Control)sender), "Please enter a numeric value for this field.");
}
}
/// <summary>
/// the event handler to check if the value of textbox is a year value(4 digits)
/// </summary>
void txtYear_Validating(object sender, CancelEventArgs e)
{
if (!AutomotiveManager.IsNumber(txtYear.Text.Trim()) || txtYear.Text.Trim().Length != 4)
{
// Prevents the validated event from being triggered
e.Cancel = true;
if (!_errorFocus)
{
((TextBox)sender).Focus();
_errorFocus = true;
}
// Show the error icon beside the control
errorProvider.SetError(txtYear, "Please enter a valid four digit year. Eg. 1977");
}
}
/// <summary>
/// Cost textbox validating
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
void txtCost_Validating(object sender, CancelEventArgs e)
{
string errorMessage = string.Empty;
if (!AutomotiveManager.IsNumber(txtCost.Text))
{
errorMessage = "Please enter a numeric value.";
}
else if (Decimal.Parse(txtCost.Text) < 0)
{
errorMessage = "Please enter a value greater than zero.";
}
if (!errorMessage.Equals(string.Empty))
{
//set the CancelEventArgs' Cancel property to true
e.Cancel = true;
//invoke SetError method in errorProvider control and set the errorMessage to Cost textbox
errorProvider.SetError(txtCost, errorMessage);
//set focus to Cost textbox
txtCost.Focus();
}
}