在对象转换匿名类型和检索一个场 [英] Cast an Anonymous Types in Object and retrieve one Field

问题描述

我用C＃ASP.NET4。

我来用匿名类型（字段：标题，类别ID），中继器的方法，直放站里面我还放置了标签：

  VAR parentCategories从context.CmsCategories C =
                               其中，c.CategoryNodeLevel == 1
                               选择新的{c.Title，c.CategoryId};
        uxRepeter.DataSource = parentCategories;
        uxRepeter.DataBind（）;
 

---

我需要改变文本属性为每个标签我对直放站事件的ItemDataBound

里面直放站

 保护无效uxRepeter_ItemDataBound（对象发件人，RepeaterItemEventArgs E）
    {
        超链接链接=（超链接）e.Item.FindControl（uxLabel）;
        uxLabel.Text = //如何在这里做!!!!!!!!
    }
 

所以，我需要设置使用e.Item（或任何一个更好的办法）为Label.Text的属性。

我的问题，我不能投e.Item（匿名类型字段标题），并将其设置为文本礼我的标签。

我明白匿名类型可强制转换为唯一对象类型，但对我来说我的匿名类型都有标题和类别ID字段。

我的问题：

如何投放和检索字段与我感兴趣？感谢您的时间呢？

编辑：
某些错误我收到：

 无法投类型的对象'＆LT;＆GT; f__AnonymousType0`2 [System.String，System.Int32]'键入'System.String'。
 

解决方案

选项约瑟夫presents是好的，但也有是的你可以做这个可怕的方式。这有点脆弱，因为它依赖于你的究竟的同样的方式在两地指定匿名类型。在这里，我们去：

 公共静态牛逼CastByExample＆LT; T＆GT;（对象输入，T为例）
{
    回报（T）输入;
}
 

然后：

 对象项目= ...; //但是你从控制值//指定了榜样使用相同的属性名称，类型和顺序
//其他地方一样。
VAR投= CastByExample（项目，新{标题=默认（串）
                                     类别ID =默认值（INT）}）;
VAR的结果= cast.Title;
 

编辑：进一步的皱纹 - 两个匿名类型创建前pressions必须在同一个组件（项目）。对不起，我忘了提，现在才

I use C# asp.net4.

I have a method to populate a Repeater with Anonymous Types (Fields: Title, CategoryId), inside the Repeater I also placed a Label:

        var parentCategories = from c in context.CmsCategories
                               where c.CategoryNodeLevel == 1
                               select new { c.Title, c.CategoryId };
        uxRepeter.DataSource = parentCategories;
        uxRepeter.DataBind();

---

I need to change Text Properties for each label inside my Repeater on Repeater Event ItemDataBound

   protected void uxRepeter_ItemDataBound(object sender, RepeaterItemEventArgs e)
    {
        HyperLink link = (HyperLink)e.Item.FindControl("uxLabel");
        uxLabel.Text = // How to do here!!!!!!!! 
    }

So I need set the properties for Label.Text using e.Item (or a better way if any).

My problem I'm not able to CAST the e.Item (Anonymous type Field Title) and set it as Text Propriety for my Label.

I understand Anonymous Type can be casted to only Object Type, but in my case my Anonymous Type has Title and CategoryId Fields.

My question:

How to cast and retrieve the field with I'm interested? Thanks for your time on this?

EDIT: SOME ERROR I RECEIVE:

Unable to cast object of type '<>f__AnonymousType0`2[System.String,System.Int32]' to type 'System.String'.

解决方案

The options Joseph presents are good ones, but there is a horrible way you can do this. It's somewhat fragile, as it relies on you specifying the anonymous type in exactly the same way in two places. Here we go:

public static T CastByExample<T>(object input, T example)
{
    return (T) input;
}

Then:

object item = ...; // However you get the value from the control

// Specify the "example" using the same property names, types and order
// as elsewhere.
var cast = CastByExample(item, new { Title = default(string),
                                     CategoryId = default(int) } );
var result = cast.Title;

EDIT: Further wrinkle - the two anonymous type creation expressions have to be in the same assembly (project). Sorry for forgetting to mention that before now.

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