[FIXED] how to validate that a floating number is not "0"

Issue

I have an <Entry> control where the user is allowed to enter decimal numbers, for examenple ...

0,2

0,02

5,405

But I do not want to enter a "0" (as a decimal), as follows

0,0

0,00

00,00

The control used in my Vista is an

MyView.XAML:

 <Entry
          HorizontalOptions="FillAndExpand"    
          Placeholder="Cantidad"
          Keyboard="Numeric"
          MaxLength="5"
          Text="{Binding CantidadEstimado}"></Entry>

To then capture the value with a string type in the following way in my ViewModel

ViewModel.CS:

    string cantidadEstimado;

   public string CantidadEstimado
        {
            get
            {
                return cantidadEstimado;
            }
            set
            {
                if (cantidadEstimado != value)
                {
                    cantidadEstimado = value.setOnlyNumbersDouble();
                    PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(CantidadEstimado)));
                }
            }
        }

As seen in my Property Amount Dear I have the call to the method setOnlyNumberDouble (), which gives the user the possibility to enter a single comma (","), I attach the following method ...

 public static string setOnlyNumbersDouble(this string s)
    {
        string sTemp = "";

        foreach (var item in s)
        {
            if (item == ',')
            {
                if (!sTemp.Contains(","))
                {
                    sTemp += item;
                }
            }
            else
            {
                sTemp += item; 
            }
        }
        return Regex.Replace(sTemp, @"[^0-9,]+", "");
    }

How can I validate that the user does not enter a "0" as a decimal? Can I reuse my setOnlyNumberDouble () method? any help for me?

Solution

You may use RegularExpressions:

bool isZero = Regex.Matches(input,"[0,]");

Or

bool isZero = int.Parse(input.Replace(",","") == 0;

Instead of trying to forcing it to be a valid double number by removing extra commas, non-numeric chars ,... try to validate it:

  public static bool IsValidDouble(this string s)
  {
      double d = 0;
      double.TryParse(s, out d);
      return d != 0; //will be false if result is 0 
      //return d > 0; if you don't want negativer values 
  }

Answered By - Ashkan Mobayen Khiabani

Answer Checked By - Robin (PHPFixing Admin)