Silverlight 4.0 Silverlight 4重写DataForm Autogenerate以插入绑定到转换器的组合框

一段时间以来，我一直在寻找解决方案，需要一些帮助。我知道我以前见过这样的例子，但今晚我找不到任何接近我需要的东西

我有一个服务，可以从缓存或DomainService为我提供所有的DropDownList。它们显示为IEnumerable，并通过GetLookup（LookupId）从存储库中请求

我已经创建了一个自定义属性，该属性修饰了MetaDataClass，如下所示：

[Lookup(Lookup.Products)]
public Guid ProductId

我已经创建了一个设置为AutoGenerateFields的自定义数据表单，我正在拦截autogenerate字段

我正在检查我的CustomAttribute，这是有效的

考虑到我的CustomDataForm中的这段代码（为简洁起见删除了标准注释），下一步是什么来覆盖字段生成并将绑定的组合框放置在它的位置

public class CustomDataForm : DataForm
{
    private Dictionary<string, DataField> fields = new Dictionary<string, DataField>();

    public Dictionary<string, DataField> Fields
    {
        get { return this.fields; }
    }

    protected override void OnAutoGeneratingField(DataFormAutoGeneratingFieldEventArgs e)
    {
        PropertyInfo propertyInfo = this.CurrentItem.GetType().GetProperty(e.PropertyName);

        foreach (Attribute attribute in propertyInfo.GetCustomAttributes(true))
        {
            LookupFieldAttribute lookupFieldAttribute = attribute as LookupFieldAttribute;
            if (lookupFieldAttribute != null)
            {                    
                //   Create a combo box.
                //   Bind it to my Lookup IEnumerable
                //   Set the selected item to my Field's Value
                //   Set the binding two way
            }
        }
        this.fields[e.PropertyName] = e.Field;
        base.OnAutoGeneratingField(e);
    }
}

我找到了解决办法

if (lookupFieldAttribute != null)
{
    ComboBox comboBox = new ComboBox();
    Binding newBinding = e.Field.Content.GetBindingExpression(TextBox.TextProperty).ParentBinding.CreateCopy();
    var itemsSource = lookupRepository.GetLookup(lookupFieldAttribute.Lookup);
    var itemsSourceBinding = new Binding { Source = itemsSource };
    comboBox.SetBinding(ItemsControl.ItemsSourceProperty, itemsSourceBinding);
    newBinding.Mode = BindingMode.TwoWay;
    newBinding.Converter = new LookupConverter(lookupRepository);
    newBinding.ConverterParameter = lookupFieldAttribute.Lookup.ToString();
    comboBox.SetBinding(ComboBox.SelectedItemProperty,newBinding);
    e.Field.Content = comboBox;                    
}

---

那么，这允许您覆盖某些自动生成的控件，但不覆盖其他控件？在

for

循环中，您到底在迭代什么？

if (lookupFieldAttribute != null)
{
    ComboBox comboBox = new ComboBox();
    Binding newBinding = e.Field.Content.GetBindingExpression(TextBox.TextProperty).ParentBinding.CreateCopy();
    var itemsSource = lookupRepository.GetLookup(lookupFieldAttribute.Lookup);
    var itemsSourceBinding = new Binding { Source = itemsSource };
    comboBox.SetBinding(ItemsControl.ItemsSourceProperty, itemsSourceBinding);
    newBinding.Mode = BindingMode.TwoWay;
    newBinding.Converter = new LookupConverter(lookupRepository);
    newBinding.ConverterParameter = lookupFieldAttribute.Lookup.ToString();
    comboBox.SetBinding(ComboBox.SelectedItemProperty,newBinding);
    e.Field.Content = comboBox;                    
}