c# - 组合框的值应显示在文本框中

组合框的值应显示在文本框中。
有一个表格，其中的属性“名称”显示在组合框中。根据在文本框中选择的值，应派生该值的“价格”属性。数据库通过ADO.NET模型连接。
我认为这行CHANNEL类型不是“ ConnectionString = @” Data Source =...。”，因为我已经连接了数据库，所以一切正常，一切都保存并更改了。剩下的唯一结论就是我的结论我是C＃的新手，我复习了很多有关此问题的课程，他们总是使用此连接字符串，而我不需要。
我使用的是Google俄语翻译成英语的翻译器，所以对您造成的误解我深感抱歉。

   namespace test6
   {
       public partial class Form5 : Form
       {
        centrEntities db;
        public Form5()
    {

        InitializeComponent();
        FillCombobox();

    }

      private void Form5_Load(object sender, EventArgs e)
    {

        db = new centrEntities();
        db.Configuration.ProxyCreationEnabled = false;
        db.Configuration.LazyLoadingEnabled = false;
        orderBindingSource.DataSource = db.order.ToList();

    }

     private void FillCombobox()
    {
        using (centrEntities c = new centrEntities())
        {

            comboService.DataSource = c.service.ToList();
            comboService.ValueMember = "serviceID";
            comboService.DisplayMember = "name";


         }
     }

Table - values

how it looks.

最佳答案

我在您的代码中向SelectedIndexChanged ComboBox添加了一个事件comboService，如下所示：

public partial class Form5 : Form
{
    centrEntities db;
    public Form5()
    {
        InitializeComponent();
        FillCombobox();
        comboService.SelectedIndexChanged += new EventHandler(comboService_SelectedIndexChanged);
    }

    private void Form5_Load(object sender, EventArgs e)
    {
        db = new centrEntities();
        db.Configuration.ProxyCreationEnabled = false;
        db.Configuration.LazyLoadingEnabled = false;
        orderBindingSource.DataSource = db.order.ToList();
    }

    private void FillCombobox()
    {
        using (centrEntities c = new centrEntities())
        {
            comboService.DataSource = c.service.ToList();
            comboService.ValueMember = "serviceID";
            comboService.DisplayMember = "name";
        }
    }

    private void comboService_SelectedIndexChanged(object sender, EventArgs e)
    {
        if (comboService.SelectedValue != null)
        {
            using (centrEntities c = new centrEntities())
            {
                var price = (from serv in c.service
                             where serv.serviceID == Convert.ToInt32(comboService.SelectedValue)
                             select serv.price).SingleOrDefault();

                TextPriceName.Text = price.ToString();
            }
        }
    }
}

关于c# - 组合框的值应显示在文本框中，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/37089622/