有效的数据源必须实现ilistsource或ienumerable [英] A valid data source must implement either ilistsource or ienumerable

问题描述

不清楚为什么以下代码返回有效数据源必须实现IListSource或IEnumerable

Not clear why following code returns "A valid data source must implement either IListSource or IEnumerable"

public class CGroup<TKey, TValue> 
{
  public TKey Key { get; set; }
  public IEnumerable<TValue> Values { get; set; }
}

//AIT is declared class
var cg = new CGroup<string, AIT>();
cg.Key = "Key Value";
//line below raises error, also tried new List<AIT>();
//Empty list is fine
cg.Values = new List<AIT>(){};
aRepeater.DataSource = cg;
aRepeater.DataBind();

感谢任何输入



我尝试了什么：



我尝试以不同的方式为cg.Values声明一个空列表，但仍然是错误。

Appreciate any input

What I have tried:

I tried declaring an empty list for cg.Values in different ways but still errors.

推荐答案

它应该是

it should be

aRepeater.DataSource = cg.Values;

，因为值属性给出 List ，其类型为 IEnumerable interface

since Values property gives the List which is of type IEnumerable interface

不幸的是，我找不到解决方案，所以不要试图用键值创建一个空的数据源（希望键值显示为空在列表中，我改为将数据源设置为null并使用标签显示空。

Unfortunately, I couldn't find the solution for this so instead of trying to create an empty datasource with a key value (was hoping the key value would display "empty" in the list), I instead set the datasource to null and used labels to display "empty".

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