C#

Member 13325846 wrote:

new OleDBCammand(“Select *From[“+txtBox1.Text+”]”,con)

public class ControlUpdater<TControl, TValue> : IReadOnlyList<TValue>
{
    private readonly List<(TControl control, TValue value)> _items = new List<(TControl, TValue)>();
    private readonly Func<TControl, TValue, bool> _setValue;
    
    public ControlUpdater(Func<TControl, TValue, bool> setValue, IEnumerable<(TControl, TValue)> items)
    {
        _setValue = setValue ?? throw new ArgumentNullException(nameof(setValue));
        if (items != null) AddRange(items);
    }
    
    public ControlUpdater(Func<TControl, TValue, bool> setValue, params (TControl, TValue)[] items) : this(setValue, items.AsEnumerable())
    {
    }
    
    public ControlUpdater(Func<TControl, TValue, bool> setValue, IEnumerable<TControl> items)
    {
        _setValue = setValue ?? throw new ArgumentNullException(nameof(setValue));
        if (items != null) AddRange(items);
    }
    
    public ControlUpdater(Func<TControl, TValue, bool> setValue, params TControl[] items) : this(setValue, items.AsEnumerable())
    {
    }
    
    public ControlUpdater(Func<TControl, TValue, bool> setValue) : this(setValue, default(IEnumerable<(TControl, TValue)>))
    {
    }
    
    public void AddRange(IEnumerable<(TControl, TValue)> items) => _items.AddRange(items);
    
    public void AddRange(IEnumerable<TControl> items, TValue value = default(TValue)) => _items.AddRange(items.Select(c => (c, value)));
    
    public void Add((TControl, TValue) item) => _items.Add(item);
    
    public void Add(TControl control, TValue value = default(TValue)) => _items.Add((control, value));
    
    public void Insert(int index, (TControl, TValue) item) => _items.Insert(index, item);
    
    public void Insert(int index, TControl control, TValue value = default(TValue)) => _items.Insert(index, (control, value));
    
    public void RemoveAt(int index) => _items.RemoveAt(index);
    
    public int Count => _items.Count;
    
    public TValue this[int index]
    {
        get 
        {
            var (_, value) = _items[index];
            return value;
        }
        set 
        {
            var (control, _) = _items[index];
            if (_setValue(control, value))
            {
                _items[index] = (control, value);
            }
        }
    }
    
    public IEnumerator<TValue> GetEnumerator()
    {
        foreach (var (_, value) in _items)
        {
            yield return value;
        }
    }
    
    IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
}

var tba = new ControlUpdater<TextBox, int>(
    (tbx, value) =>
    {
        tbx.Text = value.ToString();
        return true;
    });

var controls = Enumerable.Range(0, 5).Select(i => new TextBox { Name = $"Ints{i + 10}" });
tba.AddRange(controls);

tba[3] = 1000;     // as expected
var xxx = tba[3];  // as expected

was also slightly confused by the value stored in the list, until I realised it was meant to be the value of the control at the specified index. It would probably be better to make that a generic type parameter as well.

BillWoodruff wrote:

Good idea ? Bad idea ?

Bastard Programmer from Hell
If you can't read my code, try converting it here[^]

Eddy Vluggen wrote:

I'd compare it to classical databinding; a oneliner that doesn't generate the UI (textBox1.Bindings.Add

BillWoodruff wrote:

Oh, I do want a code review ... I can only benefit from whatever my peers, and mentors, here, say !

BillWoodruff wrote:

here the issue is binding a group of TextBoxes' 'Text property to elements in a List of Int32. Can you post a short example of doing this ?

for (int i=0; i<myIntList.Count)
  myNumericUpDownList[i].DataBindings.Add("Text", myIntList[i], "Port");

Bastard Programmer from Hell
If you can't read my code, try converting it here[^]

Eddy Vluggen wrote:

TBoxes is an abbreviation (hope I spelled that right). Since it is a private property, I wonder whether it should be a private field, an internal/public property, or a read-only property.

BillWoodruff wrote:

what does "Port" refer to ?

BillWoodruff wrote:

Mapping a Property of one Control to another in WinForm is one of the simpler databinding tasks, but, in this case the tricky part is that the List elements change, not the Control ... am I missing the point ?

Bastard Programmer from Hell
If you can't read my code, try converting it here[^]

Eddy Vluggen wrote:

I'm missing the statement where these textboxes are assigned to the owning control. How is the tab-order of your generated textboxes?

BillWoodruff wrote:

But, me brain immediately starts shakin' my head at these ideas

Bastard Programmer from Hell
If you can't read my code, try converting it here[^]

SqlConnection con = new SqlConnection("server = MUNESH;Database=datastore;UID=sa;Password=123;");

        SqlCommand cmd = new SqlCommand("Select * from data1", con);

        try

        {

            SqlDataAdapter da = new SqlDataAdapter();
            da.SelectCommand = cmd;
            DataTable dt = new DataTable();
            da.Fill(dt);
            BindingSource bsource = new BindingSource ();
            bsource .DataSource = dt;
            dataGridView1.DataSource = bsource ;
            da.Update(dt);
            DataSet ds = new DataSet("New_DataSet");
            ds.Locale = System.Threading.Thread.CurrentThread.CurrentCulture;
            da.Fill( dt );
            ds.Tables.Add( dt );
            ExcelLibrary. DataSetHelper.CreateWorkBook("MyFirstExcelSheet.xls" ,ds);

        }

        catch (Exception ec)

        {

            MessageBox.Show(ec.Message);

        }