插入后，C＃实体框架和刷新列表框 [英] C# Entity Framework and refreshing listBox after insert

问题描述

我有这个代码的问题：

public partial class KnihovnyForm : Form
{
    DatabazeEntities db;

    public KnihovnyForm()
    {
        InitializeComponent();

        db = new DatabazeEntities();

        knihovnyListBox.DataSource = db.Knihovny;
        knihovnyListBox.DisplayMember = "Nazev";
    }

    protected override void OnFormClosed(FormClosedEventArgs e)
    {
        base.OnFormClosed(e);
        db.Dispose();
    }


    private void novaButton_Click(object sender, EventArgs e)
    {
        string text = "";
        if (InputForm.ShowDialog("Název nové knihovny", ref text) == DialogResult.OK)
        {
            Knihovna n = new Knihovna() { Nazev = text };
            db.AddToKnihovny(n);
            db.SaveChanges();

            CurrencyManager cm = (CurrencyManager)BindingContext[db.Knihovny];
            cm.Refresh();
        }
    }
}

当我添加新项目数据库，我想要在列表框中显示。但是看起来实体框架不会更新上下文或类似的东西。如果我关闭此表单并再次打开，则所有项目（包括新的）将正确显示。插入后如何立即显示所有项目？

When I add new item to database, i want to show it in the listBox. But it looks like the Entity Framework don't update context or something like that. If i close this form and open it again all items (including the new one) are show correctly. How can I show all items immediately after insert?

对不起，我的英文和一些捷克语的代码。 （字典：Knihovny - >书架，Nazev - >名称）

Sorry for my english and some Czech words in code. (Dictionary: Knihovny -> Bookcase, Nazev -> Name)

推荐答案

您需要添加一个DataBinding。请查看此或这个。

You need to add a DataBinding. Have a look at this or this.

初始化时设置DataSource将获取当前值，但动态更新需要绑定。

Setting the DataSource on initialization gets the current value, but dynamic updates require a binding.

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