Only allow two digits after decimal in textbox?

Question

I have a textbox where the user enters a number, but how can i make it so that if they type the \'.\' after it it only allows 2 decimal places?

private void          


        

Answer 1

namespace WindowsFormsApplication10
{
public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }

    private void button1_Click(object sender, EventArgs e)
    {
        label1.Text = "";
        double no;
        no = double.Parse(textBox1.Text);

        string[] ones = new string[19] {"one ","two ","three ","four ","five ","six ","seven ","eight ","nine ","ten ","eleven ","twele ",
                                        "thiten ","fourten ","fiften ","sixten ","seventeen ","eighteen ", "ninteen "};
        string[] tens = new string[9] { "ten ", "twenty ", "thirty ", "fourty ", "fifty ", "sixty ", "seventy ", "eighty ", "ninty " };

        int i=0;




        if (no > 999 & no < 100000)
        {
            i = (int)no / 1000;
            if (i < 20)
                label1.Text = label1.Text + ones[i - 1] + "";
            else if (i > 20)
            {
                int r = 0;
                r = i % 10;
                i = i / 10;
                label1.Text = label1.Text + tens[i - 1] + "";
                label1.Text = label1.Text + ones[r - 1] + "";

            }

            label1.Text = label1.Text + "thousand ";
            no = no % 1000;
        }

        if (no > 99 & no < 1000)
        {
            i = (int)no / 100;
            label1.Text = label1.Text + ones[i - 1] + "hundred ";
            no = no % 100;
        }
        if (no > 19 & no < 99)
        {
            i = (int)no / 10;
            label1.Text = label1.Text + tens[i - 1];
            no = no % 10;
        }
        if (no > 0 & no < 20)
        {
            label1.Text = label1.Text + ones[(int)no-1] + " ";
        }
        label1.Text = label1.Text + "Rupees ";


    }

    private void button2_Click(object sender, EventArgs e)
    {
        textBox1.Text = "";
        label1.Text = "";
        textBox1.Focus();

    }

    private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
    {

        if (!char.IsControl(e.KeyChar)
     && !char.IsDigit(e.KeyChar)
     && e.KeyChar != '.')
        {
            e.Handled = true;
        }

        // only allow one decimal point 
        if (e.KeyChar == '.'
            && (sender as TextBox).Text.IndexOf('.') > -1)
        {
            e.Handled = true;
        }
        string word = textBox1.Text.Trim();
        string[] wordArr = word.Split('.');
        if (wordArr.Length > 1)
        {
            string afterDot = wordArr[1];
            if (afterDot.Length > 1)
            {

                e.Handled = true;
            }
        }

    }
}
}

here is the program you need.