DataGridView和List的DataBinding与BindingSource [英] DataBinding of DataGridView and List<> with BindingSource
问题描述
BindingSource
绑定数据应该是工作我想要一个
DataGridView
在更新列表时填充 List
的内容。 我可以看到列表
增长,并在我检查调试器时验证是否正在填充。当列表
更改时,我认为 BindingSource
将触发一个事件。但是没有一个可用的被解雇。基本列表更改时,如何收到通知?
我按照说明操作,并具有以下测试代码:
数据d;
BindingSource bs;
public Form1()
{
InitializeComponent();
bs = new BindingSource();
d = new Data();
}
private void Form1_Load(object sender,EventArgs e)
{
bs.DataSourceChanged + = new EventHandler(bs_DataSourceChanged);
bs.ListChanged + = new ListChangedEventHandler(bs_ListChanged);
bs.DataMemberChanged + = new EventHandler(bs_DataMemberChanged);
bs.CurrentChanged + = new EventHandler(bs_CurrentChanged);
bs.CurrentItemChanged + = new EventHandler(bs_CurrentItemChanged);
bs.DataSource = d.list;
dataGridView1.DataSource = bs;
}
// ...所有处理方法在VS中都有一个断点。
private void button1_Click(object sender,EventArgs e)
{
d.addOneItem();
}
列表< T>
不支持更改事件; BindingList< T>
将是支持此场景的好替代品,如果您的类型 T $ c,它也支持项目级更改事件$ c>实现
INotifyPropertyChanged
。
在3.0及更高版本中,还有 ObservableCollection< T>
,其作用类似于 BindingList< T>
。所有这些都归结为诸如 IBindingList
, IBindingListView
等的界面。
来自评论;对于将 Find
添加到 BindingList< T>
中的2.0 / 3.0示例:
public class MyBindingList< T> :BindingList< T>
{
public T Find(谓词< T>谓词)
{
if(predicate == null)throw new ArgumentNullException(predicate);
foreach(此项中的T项)
{
if(predicate(item))return item;
}
返回默认(T);
}
}
请注意,在3.5(或.NET 2.0 / 3.0与LINQBridge和C#3.0)你不需要这个 - 任何LINQ扩展方法都会做同样的事情。
I'm trying to figure out how data binding with BindingSource
is supposed to work
I want a DataGridView
to be populated with the content of a List<>
upon update of the list.
I can see the List
grow and verify it's being filled when I check the debugger. I thought the BindingSource
would fire an event when the List
is changed. But none of the available is fired. How do I become notified when the underlying list is changed?
I follow the instructions and have the following test code:
Data d;
BindingSource bs;
public Form1()
{
InitializeComponent();
bs = new BindingSource();
d = new Data();
}
private void Form1_Load(object sender, EventArgs e)
{
bs.DataSourceChanged += new EventHandler(bs_DataSourceChanged);
bs.ListChanged += new ListChangedEventHandler(bs_ListChanged);
bs.DataMemberChanged += new EventHandler(bs_DataMemberChanged);
bs.CurrentChanged += new EventHandler(bs_CurrentChanged);
bs.CurrentItemChanged += new EventHandler(bs_CurrentItemChanged);
bs.DataSource = d.list;
dataGridView1.DataSource = bs;
}
// ... all the handling methods caught with a break point in VS.
private void button1_Click(object sender, EventArgs e)
{
d.addOneItem();
}
List<T>
doesn't support change events; BindingList<T>
would be a good substitute to support this scenario, and it also supports item-level change events if your type T
implements INotifyPropertyChanged
.
In 3.0 and above, there is also ObservableCollection<T>
, which acts similarly to BindingList<T>
. It all comes down to interfaces such as IBindingList
, IBindingListView
, etc.
From comments; for a 2.0/3.0 example of adding a Find
to BindingList<T>
:
public class MyBindingList<T> : BindingList<T>
{
public T Find(Predicate<T> predicate)
{
if (predicate == null) throw new ArgumentNullException("predicate");
foreach (T item in this)
{
if (predicate(item)) return item;
}
return default(T);
}
}
Note that in 3.5 (or in .NET 2.0/3.0 with LINQBridge and C# 3.0) you don't need this - any of the LINQ extension methods would do the same thing.
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