Try this code ! I hope this helps. Let me know if I can assist you further.
This is auxiliary function i have written
private bool alreadyExist(string _text , ref char KeyChar)
{
if (_text.IndexOf('.')>-1)
{
KeyChar = '.';
return true;
}
if (_text.IndexOf(',') > -1)
{
KeyChar = ',';
return true;
}
return false;
}
This your key press event handler
private void txtValormetrocubico_KeyPress(object sender, KeyPressEventArgs e)
{
if (!char.IsControl(e.KeyChar)
&& !char.IsDigit(e.KeyChar)
&& e.KeyChar != '.' && e.KeyChar != ',')
{
e.Handled = true;
}
//check if '.' , ',' pressed
char sepratorChar='s';
if (e.KeyChar == '.' || e.KeyChar == ',')
{
// check if it's in the beginning of text not accept
if (txtValormetrocubico.Text.Length == 0) e.Handled = true;
// check if it's in the beginning of text not accept
if (txtValormetrocubico.SelectionStart== 0 ) e.Handled = true;
// check if there is already exist a '.' , ','
if (alreadyExist(txtValormetrocubico.Text , ref sepratorChar)) e.Handled = true;
//check if '.' or ',' is in middle of a number and after it is not a number greater than 99
if (txtValormetrocubico.SelectionStart != txtValormetrocubico.Text.Length && e.Handled ==false)
{
// '.' or ',' is in the middle
string AfterDotString = txtValormetrocubico.Text.Substring(txtValormetrocubico.SelectionStart);
if (AfterDotString.Length> 2)
{
e.Handled = true;
}
}
}
//check if a number pressed
if (Char.IsDigit(e.KeyChar))
{
//check if a coma or dot exist
if (alreadyExist(txtValormetrocubico.Text ,ref sepratorChar))
{
int sepratorPosition = txtValormetrocubico.Text.IndexOf(sepratorChar);
string afterSepratorString = txtValormetrocubico.Text.Substring(sepratorPosition + 1 );
if (txtValormetrocubico.SelectionStart > sepratorPosition && afterSepratorString.Length >1)
{
e.Handled = true;
}
}
}
}