如何将集合传递给 Silverlight 中的绑定转换器参数答案

【问题标题】：How to pass collection to binding converter parameter in silverlight如何将集合传递给 Silverlight 中的绑定转换器参数
【发布时间】：2014-01-26 13:01:24
【问题描述】：

在 c# 代码中的 silverlight 应用程序中，我从 WCF RIA 服务获取数据。然后我想将这个数据（List）传递给图表（System.Windows.Forms.DataVisualization.Charting.Chart）轴转换器参数。

this.specialDayClient = new SpecialDayClient();
            this.specialDayClient.SpecialDayLoaded += new EventHandler(specialDayClient_SpecialDaysLoaded);
            this.specialDayClient.SpecialDayLoadFailed += new EventHandler(specialDayClient_SpecialDaysLoadFailed);

        private void specialDayClient_SpecialDaysLoaded(object sender, EventArgs e)
        {
            specialDays = sender as IEnumerable<SpecialDay>;
            var binding = new Binding("ConverterBinding")
            {
                Converter = new DateToColorConverter(),
                ConverterParameter = specialDays
            };

        var setter = new Setter(ForegroundProperty, binding);


            ((DateTimeAxis)chartCashRemainders.Axes[0]).AxisLabelStyle.Setters.Add(setter);
            //After this row I get error message "Error HRESULT E_FAIL has been returned from a call to a COM component."
        }

        private void specialDayClient_SpecialDaysLoadFailed(object sender, EventArgs e)
        {
            specialDays = new List<SpecialDay>();
        }

在 ((DateTimeAxis)chartCashRemainders.Axes[0]).AxisLabelStyle.Setters.Add(setter); 之后，我收到错误消息“错误 HRESULT E_FAIL 已从调用COM 组件。”

我的错误在哪里？

【问题讨论】：

标签： c# silverlight xaml collections converter

【解决方案1】：

好的，最简单的方法——用对象集合创建一个新类：

public class SpecialDays : List<SpecialDay>
{
    public SpecialDays()
    {
        if(DesignerProperties.IsInDesignTool)
            return;

        DeviceManagementDomainContext domainContext = new DeviceManagementDomainContext();

        var query = domainContext.GetSpecialDaysForEditorQuery();
        LoadOperation<SpecialDay> operation = domainContext.Load(query);
        operation.Completed += (s, e) =>
        {
            if (operation.HasError)
            {
                if (operation.Error != null)
                {
                    operation.MarkErrorAsHandled();
                }
                this.AddRange(new List<SpecialDay>());
            }
            else
            {
                List<SpecialDay> specialDays = operation.Entities.ToList();
                this.AddRange(specialDays);

            }
        };
    }
}

然后在xaml代码中添加这个类（到）：

   <UserControl.Resources>
        <bs2Models:SpecialDays x:Key="SpecialDays"/>
    </UserControl.Resources>

并作为静态资源添加到转换器：

<Style x:Key="HorizontalAxisLabelStyle" TargetType="toolkit:DateTimeAxisLabel">
            <Setter Property="Foreground" Value="{Binding Converter={StaticResource DateToColorConverter}, ConverterParameter={StaticResource SpecialDays}}"/>
</Style>

【讨论】：