Format Textbox for thousands?

Question

I’m trying to create a Textbox to report values in thousands, the values will be for weights(kilos). I want to type the values from right to left based on the mask 0,000 and as the user type the weight the values are overwritten in the zeros... For example: 0,000 typing the 1 will stay 0,001 and so successively, if the user deletes the 1 the mask returns to 0,000 as in standard.

I found an example to do this that works very well, but the class is for monetary values and I’m trying to adapt to use weights but I’m not able to adapt.

How to do this ?

Here’s the Currency class I’m using as an example to adapt the Weight class.

public class Moeda  {
        private TextBox txtBox;
        private String txt = string.Empty;
        private Decimal valor = 0;

        public Moeda(TextBox txtBox) {
            this.txtBox = txtBox;
            this.txtBox.RightToLeft = RightToLeft.Yes;
            this.txtBox.Text = "0,00";
            this.txtBox.KeyPress += keyPress;
            this.txtBox.TextChanged += new EventHandler(textChanged);            
            this.txtBox.Font = new Font(this.txtBox.Font, FontStyle.Bold);            
        }

        private void textChanged(object obj, EventArgs e) {
            try {
                txt = txtBox.Text.Replace(",", "").Replace(".", "");
                if (txt.Equals("")) {
                    txtBox.Text = "0,00";
                }
                txt = txt.PadLeft(3, '0');                
                if (txt.Length > 3 & txt.Substring(0, 1) == "0")
                    txt = txt.Substring(1, txt.Length - 1);
                valor = Convert.ToDecimal(txt) / 100;
                txtBox.Text = string.Format("{0:N}", valor);
                txtBox.SelectionStart = txtBox.Text.Length;
            }catch (Exception ex) {
                Console.WriteLine(ex.Message);
            }            
        }

        private void keyPress(object obj, KeyPressEventArgs e) {
            if (!(Char.IsDigit(e.KeyChar) || Char.IsControl(e.KeyChar))) { e.Handled = true; }
        }
    }

Here’s the weight class I’m trying to adapt based on the currency class.

public class Peso  {
        private TextBox txtBox;
        private String txt = string.Empty;
        private Decimal valor = 0;

        public Peso(TextBox txtBox) {
            this.txtBox = txtBox;
            this.txtBox.RightToLeft = RightToLeft.Yes;             
            this.txtBox.Text = "0,000";
            this.txtBox.KeyPress += keyPress;
            this.txtBox.TextChanged += new EventHandler(textChanged);           
            this.txtBox.Font = new Font(this.txtBox.Font, FontStyle.Bold);            
        }

        private void textChanged(object obj, EventArgs e) {
            try {
                txt = txtBox.Text.Replace(",", "").Replace(".", "");
                if (txt.Equals("")) {
                    txtBox.Text = "0,000";
                }
                txt = txt.PadLeft(4, '0');
                if (txt.Length > 4 & txt.Substring(0, 1) == "0")
                    txt = txt.Substring(1, txt.Length - 1);
                valor = Convert.ToDecimal(txt);
                txtBox.Text = string.Format("{0:N}", valor);
                txtBox.SelectionStart = txtBox.Text.Length;
            }catch (Exception ex) {
                Console.WriteLine(ex.Message);
            }       
        }


        private void keyPress(object obj, KeyPressEventArgs e) {
            if (!(Char.IsDigit(e.KeyChar) || Char.IsControl(e.KeyChar))) { e.Handled = true; }
        }


    }

Answer 1

Friend, I discovered that if you divide the "value" by 1000, it results in the format with 3 zeros before the comma as you want. Modifies this line:

valor = Convert.ToDecimal(txt); 

at this value:

valor = Convert.ToDecimal(txt) / 1000; 

and thus complements:

txtBox.Text = String.Format("{0:N3}", valor);

I hope it helps.