what about maskedtextbox as check?

Valerie Meunier

My last question about checking a textbox for integer or double.

An easier way is to use markedtextbox. But Is it a good option when i don't know how many digits and how many decimals the number will have?

Thanks

5 Replies

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Sachin Singh4y ago
Accepted answer
This is the complete code snippet
private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{
    // Verify that the pressed key isn't CTRL or any non-numeric digit
    if (!char.IsControl(e.KeyChar) && !char.IsDigit(e.KeyChar) && (e.KeyChar != '.'))
    {
        e.Handled = true;
    }

    // If you want, you can allow decimal (float) numbers
    if ((e.KeyChar == '.') && ((sender as TextBox).Text.IndexOf('.') > -1))
    {
        e.Handled = true;
    }
}
To retrieve its value, you would need only to convert the string to a number by using the desired type:

string textboxValue = textBox1.Text;

// Retrieve as decimal
decimal valueDec = decimal.Parse(textboxValue);

// Retrieve as integer
int valueInt = Int32.Parse(textboxValue);
example credit:- https://ourcodeworld.com/articles/read/507/how-to-allow-only-numbers-inside-a-textbox-in-winforms-c-sharp
Valerie Meunier4y ago
Ok, i found my mistake. I have to enter a comma ',' instead of a dot '.' because of the language of my Windows version. So it works.
Valerie Meunier4y ago
Thanks, but sorry, i have still '455' in a label when I enter 45.5 in the textbox or '5' when entering '0.5':

private void button1_Click(object sender, EventArgs e)
{
string textboxValue = textBox1.Text;
decimal valueDec = decimal.Parse(textboxValue);
label2.Text = valueDec.ToString();
}
Valerie Meunier4y ago
Thanls again.
I come back to my previous question.
First: I have added && e.KeyChar != '.' at the end of the line because otherwise, i couldn't enter a dot ('.') for decimal digits).
Then: i don't get a decimal number in the label. If I enter 55.78, I get 5578.

private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{ e.Handled = !char.IsDigit(e.KeyChar) && !char.IsControl(e.KeyChar) && e.KeyChar != '.'; }

private void button1_Click(object sender, EventArgs e)
{
string textboxValue = textBox1.Text;
double valueInt = Convert.ToDouble(textboxValue);
label2.Text = valueInt.ToString(); // no dot
}

Just to understand.
Thanks
Sachin Singh4y ago
No, masked textbox is not a good fit for such situation, numericupdown is the best fit for you. The NumericUpDown.DecimalPlaces property supports up to 99 decimal places.
Or, better create a custom control as per your specific requirement as discussed here with example
https://stackoverflow.com/questions/14432659/masked-textbox-with-decimal-numbers