I added 3 columns.

The modified attribute values are as follows.

1. View - Details
2. Onwer - True
3. GirdLines - True
4. FullRowSelect - True

namespace TestWinForm
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
    
        private void add_Click(object sender, EventArgs e)
        {
            //listView1.BeginUpdate();
            string[] row = { "123", "456", "789" };
            ListViewItem list_view = new ListViewItem(row);
            listView1.Items.Add(list_view);
            textBox1.Text = listView1.Items.Count.ToString();
            //listView1.EndUpdate();
        }
    }
}

It is a code that updates the number of current rows to the textbox1 after adding a data row every time the add button is clicked.

Obviously, The number of rows keeps going up.... but the data is not output to listView1.

Which part should I check?

CodePudding user response：

Havent used Winforms in ages, but I remember that using a binding source was more reliable

var bindingSource = new BindingSource();
bindingSource.DataSource = dataTable;
grid.DataSource = bindingSource;

//Add data to dataTable and then call

bindingSource.ResetBindings(false)  

CodePudding user response：

What you have should work in detail view with columns added. Here is an example

Design view

In this case a instance of the following class is used so later we can get information about a specific row.

public class Contact
{
    public int CustomerIdentifier { get; set; }
    public string CompanyName { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public string PhoneTypeDescription { get; set; }
    public string PhoneNumber { get; set; }
    public string CountryName { get; set; }
    public string[] ItemArray => new[]
    {
        CompanyName,
        FirstName,
        LastName,
        PhoneNumber,
        CountryName
    };
}

Code to do a mock add

private void AddRowButton_Click(object sender, EventArgs e)
{
    var companyName = "Just added";

    Contact contact = new Contact()
    {
        CompanyName = companyName,
        FirstName = "Karen",
        LastName = "Payne",
        PhoneNumber = "123-333-4444",
        CountryName = "USA"
    };

    ownerContactListView.Items.Add(
        new ListViewItem(contact.ItemArray)
        {
            Tag = contact.CustomerIdentifier
        });

    CountLabel.Text = $@"Row count: {ownerContactListView.Items.Count}";

    var index = ownerContactListView.Items.IndexOf(
        ownerContactListView.FindItemWithText(companyName));

    ownerContactListView.Items[index].Selected = true;
    ownerContactListView.EnsureVisible(index);
    ActiveControl = ownerContactListView;
}

After adding the row above (note I shorten the form so what you see is a partial view)

You can see the entire the initial load, see the following.