public class StringToIconConverter : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            if (value != null)
            {
                return Regex.Unescape(StringToUnicode(value.ToString()));
            }
            return value;
        }
        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            throw new NotImplementedException();
        }

        /// <summary>  
        /// 字符串轉為UniCode碼字符串  
        /// </summary>  
        public static string StringToUnicode(string s)
        {
            if (!string.IsNullOrEmpty(s))
            {
                //這里把格式&#xe625; 轉為 \ue625
                return s.Replace(@"&#x",@"\u").Replace(";","");
            }
            return s;
        }
    }

<!--IconStyle-->
    <Style x:Key="IconStyle" TargetType="TextBlock">
        <Setter Property="FontFamily" Value="/Framework;component/Fonts/#iconfont"></Setter>
        <Setter Property="TextAlignment" Value="Center"/>
        <Setter Property="HorizontalAlignment" Value="Center"/>
        <Setter Property="VerticalAlignment" Value="Center"/>
        <Setter Property="FontSize" Value="16"/>
    </Style>

<StackPanel Orientation="Horizontal" VerticalAlignment="Center" HorizontalAlignment="Center">
  <TextBlock Text="{Binding Path=Authority_icon,Converter={x:Static local:ConverterUtil.StringToIconConverter}}" Style="{StaticResource IconStyle}"/>
</StackPanel>