如何将数据源转换为List< T&gt ;？ [英] How to Casting DataSource to List<T>?

问题描述

我有以下方法可以在DataGridView上加载产品

I have the following method that load products on a DataGridView

private void LoadProducts(List<Product> products)
{
    Source.DataSource = products;  // Source is BindingSource
    ProductsDataGrid.DataSource = Source;
}

现在，我正试着给我回去保存它们，如下所示

And now I'm trying to give me back to save them as shows below.

private void SaveAll()
{
   Repository repository = Repository.Instance;
   List<object> products = (List<object>)Source.DataSource; 
   Console.WriteLine("Este es el número {0}", products.Count);
   repository.SaveAll<Product>(products);
   notificacionLbl.Visible = false;
}

但是我收到了 InvalidCastException 在此行上：

But I get an InvalidCastException on this line:

List<object> products = (List<object>)Source.DataSource;

那么如何将数据源转换为列表？

So how can I cast the DataSource to an List?

推荐答案

您不能将协变直接转换为List；

You can't cast covariantly directly to List;

其中之一：

List<Product> products = (List<Product>)Source.DataSource;

或：

List<Object> products = ((List<Product>)Source.DataSource).Cast<object>().ToList();

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