RatioConverter.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Data;

namespace FLY.ControlLibrary.Converter
{
    /// <summary>
    /// 3个输入, 
    /// [0]比例分子;
    /// [1]比例分母;
    /// [2]控件最大长度
    /// </summary>
    public class RatioConverter: IMultiValueConverter
    {
        #region IMultiValueConverter 成员

        public object Convert(object[] values, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            if (values.Length == 3 && (values[0] is int) && (values[1] is int) && (values[2] is double))//必须要检查，不然 界面生成器 会错误，提示转换异常
            {
                double ratio ;
                int value = (int)values[0];
                if (value == 99999998)
                    value = 0;
                int max = (int)values[1];
                double ActualWidth = (double)values[2];


                if(max <=0)
                    ratio = 0;
                else
                    ratio = (double)value / max;

                if (ratio < 0)
                    ratio = 0;
                else if (ratio > 1)
                    ratio = 1;

                return ActualWidth * ratio;
            }
            else 
            {
                return 100;
            }
        }

        public object[] ConvertBack(object value, Type[] targetTypes, object parameter, System.Globalization.CultureInfo culture)
        {
            return null;
        }

        #endregion
    }

    public class RatioConverter_TimeSpan : IMultiValueConverter
    {
        #region IMultiValueConverter 成员

        public object Convert(object[] values, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            if (values.Length == 3 && (values[0] is TimeSpan) && (values[1] is TimeSpan) && (values[2] is double))//必须要检查，不然 界面生成器 会错误，提示转换异常
            {
                double ratio;
                TimeSpan v = (TimeSpan)values[0];
                TimeSpan max = (TimeSpan)values[1];
                double ActualWidth = (double)values[2];

                if (max.TotalSeconds <= 0)
                    ratio = 0;
                else
                    ratio = v.TotalSeconds / max.TotalSeconds;

                if (ratio < 0)
                    ratio = 0;
                else if (ratio > 1)
                    ratio = 1;

                return ActualWidth * ratio;
            }
            else
            {
                return 100;
            }
        }

        public object[] ConvertBack(object value, Type[] targetTypes, object parameter, System.Globalization.CultureInfo culture)
        {
            return null;
        }

        #endregion
    }
}