绑定列表到数据源 [英] Bind List to DataSource

问题描述

我希望能够到一个列表绑定到一个列表框的数据源，并在列表被修改，列表框的UI自动更新。 （没有的WinForms ASP）。
下面是一个例子：

 私人列表<富> fooList =新的List<富>（）; 
 
私人无效Form1_Load的（对象发件人，EventArgs五）
 {
 //添加第一美孚在fooList 
美孚foo1 =新的Foo（BAR1）; 
 fooList.Add（foo1）; 
 
 //绑定fooList到列表框
 listBox1.DataSource = fooList; 
 //我可以看到在BAR1预期的列表框
} 
 
私人无效的button1_Click（对象发件人，EventArgs五）
 {
 //添加anthoter美孚在fooList 
富foo2的=新的Foo（BAR2）; 
 fooList.Add（foo2的）; 
 //我期望列表框UI进行更新感谢INotifyPropertyChanged的，但它不是
} 
 
类Foo：INotifyPropertyChanged的
 {
私人字符串bar_ ; 
公共串吧
 {
 {返回bar_; } 
组
 {
 bar_ =价值; 
 NotifyPropertyChanged（酒吧）; 
} 
} 
 
公共美孚（串吧）
 {
 this.Bar =栏; 
} 
 
公共事件PropertyChangedEventHandler的PropertyChanged; 
 
私人无效NotifyPropertyChanged（字符串信息）
 {
如果（的PropertyChanged！= NULL）
 {
的PropertyChanged（这一点，新PropertyChangedEventArgs（信息）） ; 
} 
} 
 
公共重写字符串的ToString（）
 {
返回bar_; 
} 
} 
  

如果我更换列表<美孚> fooList =新的List<富>（）; 按的BindingList<富> fooList =新的BindingList<富>（）; 然后它工作。但我不想改变原有的类型foolist的。我想是这样的工作： listBox1.DataSource =新的BindingList<富>（fooList）;

编辑：另外我刚刚读到这里名单< T> VS的BindingList< T>优点/缺点从伊利亚Jerebtsov 的：当你设置的BindingSource的DataSource到List<>，它在内部创建一个的BindingList来包装你的名单。我觉得我的样本只是表明，这是不正确的：我的名单，LT;>似乎并没有在内部被裹成的BindingList<>

解决方案

您没有 BindingSource的你例子。

您需要修改它像这样使用的BindingSource

 变种BS =新的BindingSource（）; 
美孚foo1 =新的Foo（BAR1）; 
 fooList.Add（foo1）; 
 
 bs.DataSource = fooList; //<  - 对interrest 
 
 //绑定fooList到列表框
 listBox1.DataSource = BS点; //<  - 笔记它需要整个的BindingSource 
  

修改

注意（如被指出在评论） - BindingSource的不 INotifyPropertyChanged的

I want to be able to bind a list to a listbox datasource and when the list is modified, the listbox's UI automatically updated. (Winforms not ASP). Here is a sample :

private List<Foo> fooList = new List<Foo>();

    private void Form1_Load(object sender, EventArgs e)
    {
        //Add first Foo in fooList
        Foo foo1 = new Foo("bar1");
        fooList.Add(foo1);

        //Bind fooList to the listBox
        listBox1.DataSource = fooList;
        //I can see bar1 in the listbox as expected
    }

    private void button1_Click(object sender, EventArgs e)
    {
        //Add anthoter Foo in fooList
        Foo foo2 = new Foo("bar2");
        fooList.Add(foo2);
        //I expect the listBox UI to be updated thanks to INotifyPropertyChanged, but it's not
    }

class Foo : INotifyPropertyChanged
{
    private string bar_ ;
    public string Bar
    {
        get { return bar_; }
        set 
        { 
            bar_ = value;
            NotifyPropertyChanged("Bar");
        }
    }

    public Foo(string bar)
    {
        this.Bar = bar;
    }

    public event PropertyChangedEventHandler PropertyChanged;

    private void NotifyPropertyChanged(string info)
    {
        if (PropertyChanged != null)
        {
            PropertyChanged(this, new PropertyChangedEventArgs(info));
        }
    }

    public override string ToString()
    {
        return bar_;
    }
}

If I replace List<Foo> fooList = new List<Foo>(); by BindingList<Foo> fooList = new BindingList<Foo>(); then it works. But I don't want to change the original type of foolist. I would like something like this to work : listBox1.DataSource = new BindingList<Foo>(fooList);

EDIT : Also I just read here List<T> vs BindingList<T> Advantages/DisAdvantages from Ilia Jerebtsov : "When you set a BindingSource's DataSource to a List<>, it internally creates a BindingList to wrap your list". I think my sample just demonstrates that this is not true : my List<> doesn't seem to be internally wrapped into a BindingList<>.

解决方案

You don't have a BindingSource in you example.

you need to modify it like this to use a BindingSource

   var bs = new BindingSource();
   Foo foo1 = new Foo("bar1");
   fooList.Add(foo1);

     bs.DataSource = fooList; //<-- point of interrest

    //Bind fooList to the listBox
    listBox1.DataSource = bs; //<-- notes it takes the entire bindingSource

Edit

Be aware that (as was pointed out in comments) - the bindingsource does not work with INotifyPropertyChanged

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