Set MaskedTextBox Value from the Right to Left

Question

I currently have a mask of #9.99 The # is there for '+' or '-' sign.

When I set the value of the Masked text box, where the value is negative it will give me the correct value.

However when the value is positive it gives me the incorrect answer.

Here is actual code to test it out. Eg.

private void Form1_Load(object sender, EventArgs e){
    double value = -0.14;
    double value2 = 0.14;

    maskedTextBox1.Text = value.ToString();
    maskedTextBox2.Text = value2.ToString();
}

Here is the result

I need it to be _0.14

Setting the Property from RightToLeft does not work because I do not want the user to type from the right to left.

Any help is greatly appreciated.

you want to have a `+` sign before the value if it's positive? — King King, Jul 17 '13 at 10:41
I want to have this show up _0.14, or even having a positive value in front could work. — Dreamer78692, Jul 17 '13 at 10:45
What kind of `MaskedTextBox` are you using? Because the standard one doesn't have `Value` property. — King King, Jul 17 '13 at 10:53

unlimit · Answer 1 · 2013-07-17T18:41:20.397

1

I think you will need to pad space:

maskedTextBox2.Text = value2.ToString().Length < maskedTextBox2.Mask.Length ? 
            value2.ToString().PadLeft(maskedTextBox2.Mask.Length,' '): value2.ToString();

Editing answer in response to OP's comment:

// Pad the left of decimal with spaces
string leftOfDecimal = value.ToString().Split('.')[0].PadLeft(maskedTextBox1.Mask.Split('.')[0].Length);
// Pad the right with 0s
string rightOfDecimal = value.ToString().Split('.')[1].PadRight(maskedTextBox1.Mask.Split('.')[1].Length,'0');

maskedTextBox1.Text = leftOfDecimal + "." + rightOfDecimal;

Note that you will have to check if the value has a decimal point or not. The code above has no such check. If you input double value = 25, it will blow up. There might be other edge cases too that you will have to handle.

edited Jul 17 '13 at 18:41

answered Jul 17 '13 at 11:39

unlimit

3,672
2
26
34

Problem with this is that if I add an extra decimal place to the mask i.e. from #9.99 to #9.999 it will give a result of __.014 instead of _0.14 – Dreamer78692 Jul 17 '13 at 13:40
In that case you will have determine the number of digits after the decimal point and pad 0s to the right and for the digits before the decimal point you will have to pad spaces to the left. See my edited answer. – unlimit Jul 17 '13 at 18:38

King King · Answer 2 · 2013-07-18T01:47:23.577

Setting Text directly as you did doesn't work because the Mask will determine how the text is display. 0.14 will become 014 first (because the dot will be ignored) and then 014 will become 01.4_ after applying format from Mask. If you want to set the Text directly, you may have to create your own MaskedTextBox, although this is easy but I want to give you the solution in which we use an extension method instead.

public static class MaskedTextBoxExtension {
   public static void SetValue(this MaskedTextBox t, double value){
      t.Text = value.ToString(value >= 0 ? " 0.00" : "-0.00");
   }
}
//I recommend setting this property of your MaskedTextBox to true
yourMaskedTextBox.HidePromptOnLeave = true;//this will hide the prompt (which looks ugly to me) if the masked TextBox is not focused.
//use the code
yourMaskedTextBox.SetValue(0.14);// =>  _0.14
yourMaskedTextBox.SetValue(-0.14);// => -0.14

Set MaskedTextBox Value from the Right to Left

2 Answers2