将double值绑定到文本框

Question

I have an ObservableCollection filling a Datagrid DGCommands , and some textboxes' Text attribute defined like the following :

Text="{Binding SelectedItem.Costs,
Mode=TwoWay,
ElementName=DGCommands,
UpdateSourceTrigger=PropertyChanged}"

Alright, now when i parse a double value from one of the textboxes, for example :

bool costs_valid = double.TryParse(txtboxCosts.Text, out _costs) // 1,8 i get 18;

I tried to solve the issue with this method but i'm not sure if it's the best possible solution :

public static double DoubleParseCostum(string val)
{
        double res = 0;
        bool res_valid = double.TryParse(val, out res);
        if (val.ToString().Contains(_DECIMAL_)) return res;
        else
        {
            if ("." != _DECIMAL_ && val.Contains(".")) return double.Parse(val.Replace(".", _DECIMAL_));
            if ("," != _DECIMAL_ && val.Contains(",")) return double.Parse(val.Replace(",", _DECIMAL_));
        }
        return res;
}

Where

_DECIMAL_ = Convert.ToChar(System.Globalization.CultureInfo.CurrentCulture.NumberFormat.NumberDecimalSeparator).ToString();

EDIT :

Changed the title from " Parsing string to double gives Int " To the current one because the real problem was in the binding and not the parsing, cuz when i want to change 1.8 to 1,8 i get 18 as result on lost focus.

Answer 1

试试这个： double.Parse("1.8", CultureInfo.InvariantCulture)

Answer 2

In this example I picked a culture (Austria) that uses the comma as a decimal separator to show how to do it. You can set the culture to anything you want, of course, including the current UI culture.

var testCulture = CultureInfo.CreateSpecificCulture("de-AT");
var text = "1,8";
double result;
var ok = double.TryParse(text, NumberStyles.Float, testCulture, out result);
Console.WriteLine("And the result is: {0:000.0000}", result);

Output:

And the result is: 001.8000

Code on DotNetFiddle

Answer 3

This is a long-shot... I'm wondering whether the underlying problem that you're actually trying to solve (without realising it) is that all WPF applications default to using the "en-US" locale. You can solve this on startup of the application by doing:

FrameworkElement
   .LanguageProperty
   .OverrideMetadata(
    typeof(FrameworkElement),
    new FrameworkPropertyMetadata(XmlLanguage.GetLanguage(CultureInfo.CurrentUICulture.IetfLanguageTag)));

Answer 4

I finally found a solution, just like @Richardissimo said, WPF uses the 'en-US' culture by default and comma (,) is then treated as a thousand separator and not as a decimal sign. so i set the ConverterCulture property to use the system's default culture :

<TextBox Name="txtboxCosts" Style="{StaticResource txtboxDefault2}"
xmlns:gl="clr-namespace:System.Globalization;assembly=mscorlib"                       
Text="{Binding SelectedItem.proCosts, 
       Mode=TwoWay,   
       ElementName=DGCommands,
       StringFormat={}{0:N2},
       UpdateSourceTrigger=PropertyChanged,
       ConverterCulture={x:Static gl:CultureInfo.CurrentCulture}}"/>