LogarithmicConverter Class

The class WPF.LogarithmicConverter converts a numeric value from a linear scale to a logarithmic scale. It can be used to provide better usability when mapping a zoom factor to a slider, for example. The range of values of the linear as well as the logarithmic scale have to be defined with the given "Minimum"- and "Maximum"-properties. Provides a possibility to define an input value which should be mapped to the center of the output range of values. The class can be used in XAML as a static resource to automatically convert bound property values.

Syntax

• C#
• VB.NET

​[ValueConversion(typeof(double), typeof(double))]
[ValueConversion(typeof(double), typeof(int))]
[ValueConversion(typeof(int), typeof(double))]
[ValueConversion(typeof(int), typeof(int))]
public class LogarithmicConverter : IValueConverter

​Public Class LogarithmicConverter
  Implements IValueConverter

Examples

The following XAML example shows how to bind the TextControl.ZoomFactor property to a slider using the LogarithmicConverter mapping a zoom range from 10 to 400 percent to a value range from 0 to 100.

• XAML

​…
xmlns:tx="clr-namespace:TXTextControl.WPF;assembly=TXTextControl.WPF"
…
<Window.Resources>
    <tx:LogarithmicConverter
        x:Key="logConv"
        InputMinimum="10"
        InputCenter="100"
        InputMaximum="400"
        OutputMinimum="0"
        OutputMaximum="100" />
</Window.Resources>
…
<Slider
    Minimum="0"
    Maximum="100"
    Value="{Binding ElementName=textControl1, Path=ZoomFactor, Converter={StaticResource logConv}}" />

Methods

Properties