System.Windows.Forms.DataGridView does not display data
All I am doing is a simple:
// Both the methods, order.GetAllOrderItems() and order.GetOrderedItemsWhereBrandIs("foo")
// return an IEnumerable<T> so the assignment to the DataSource property of the DataGridView
// should be fine. The problem is in re-assigning the data source property.
public void DisplayItems()
{
// The data appears if I have just this line.
dgvOrderedItems.DataSource = order.GetAllOrderItems();
dgvOrderedItems.DataSource = null;
// This time the data grid does not take the new data source. Instead, because
// of the null assignment in the previous statement, it displays no data at all.
dgvOrderedItems.DataSource = order.GetOrderedItemsWhereBrandIs("Lenovo");
}
My question is: is there a way to change the data source of a D开发者_开发技巧ataGridView control once it has been set? I am using C# 4.0 and Visual Studio 2010 for development.
Databinding cannot be used with IEnumerable
s; you can only bind to an IList
or better.
Add .ToArray()
to turn the IEnumerable
into an IList<T>
.
The reason it works the first time is probably because your GetAllOrderItems
doesn't perform any LINQ calls and ends up returning an object that implements IList
.
However, since your GetOrderedItemsWhereBrandIs
method (presumably) includes a Where()
call, it returns an object that only implements IEnumerable
.
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