wpf - A generic Boolean Convertor -

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i have following converter 

  [valueconversion(typeof(bool), typeof(visibility))] public sealed class booltovisibilityconverter : ivalueconverter {     public visibility truevalue { get; set; }     public visibility falsevalue { get; set; }      public booltovisibilityconverter()     {         // set defaults         truevalue = visibility.visible;         falsevalue = visibility.collapsed;     }      public object convert(object value, type targettype,         object parameter, cultureinfo culture)     {         if (!(value bool))             return null;         return (bool)value ? truevalue : falsevalue;     }      public object convertback(object value, type targettype,         object parameter, cultureinfo culture)     {         if (equals(value, truevalue))             return true;         if (equals(value, falsevalue))             return false;         return null;     } } 
<conv:boolconverter x:key="enablestyleconvertor" truevalue="visible" falsevalue="collapsed" />

is there way make more generic, ie can return type of object?

you make truevalue , falsevalue of type object. may want update equals code see if objects implement icomparable though.

[valueconversion(typeof(bool), typeof(object))] public sealed class myconverter : ivalueconverter {     public object truevalue { get; set; }     public object falsevalue { get; set; }      public object convert(object value, type targettype,         object parameter, cultureinfo culture)     {         if (!(value bool))             return null;         return (bool)value ? truevalue : falsevalue;     }      public object convertback(object value, type targettype,         object parameter, cultureinfo culture)     {         if (isequal(value, truevalue))             return true;         if (isequal(value, falsevalue))             return false;         return null;     }      private static bool isequal(object x, object y) {         if (equals(x, y))           return true;          icomparable c = x icomparable;         if (c != null)            return (c.compareto(y) == 0);          return false;     } }

to use you'd need explicitly define values though:

<local:myconverter>     <local:myconverter.truevalue>         <visibility>visible</visibility>     </local:myconverter.truevalue>     <local:myconverter.falsevalue>         <visibility>collapsed</visibility>     </local:myconverter.falsevalue> </local:myconverter>

edit:

a generic version this:

[valueconversion(typeof(bool), typeof(object))] public sealed class myconverter<t> : ivalueconverter {     public t truevalue { get; set; }     public t falsevalue { get; set; }      public object convert(object value, type targettype,         object parameter, cultureinfo culture) {         if (!(value bool))             return null;         return (bool)value ? truevalue : falsevalue;     }      public object convertback(object value, type targettype,         object parameter, cultureinfo culture) {         if (isequal(value, truevalue))             return true;         if (isequal(value, falsevalue))             return false;         return null;     }      private static bool isequal(object x, object y) {         if (equals(x, y))             return true;          icomparable c = x icomparable;         if (c != null)             return (c.compareto(y) == 0);          return false;     } }

this isn't accessible xaml though. xaml 2009 has additional support generics, loose xaml files (i.e. not compiled).


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