根据用户类型从API设置动态数据源

我的要求是

1)。用户应该能够键入输入2).需要通过查询web api获取给定输入的每个按键的匹配结果。3).结果应以下拉式显示。用户应该能够从项目列表中选择任何项目。4).需要用选中的项目文本查询API获取详细信息

为了实现上述目标，我采用了一个组合框来处理keyup和keydown事件。

这是我的代码。

private void cmbSearch_KeyDown(object sender, KeyEventArgs e)
        {
            try
            {
                if (e.KeyCode == Keys.Up || e.KeyCode == Keys.Down)
                {
                    isKeyDownOrKeyUp = true;
                }
                else
                {
                    isKeyDownOrKeyUp = false;
                }
                if (e.KeyCode == Keys.Up || e.KeyCode == Keys.Down || e.KeyCode == Keys.Left || e.KeyCode == Keys.Right || e.KeyCode == Keys.LShiftKey || e.KeyCode == Keys.RShiftKey || e.KeyCode == Keys.Shift || e.KeyCode == Keys.ShiftKey || e.KeyCode == Keys.Select || e.KeyCode == Keys.Control || e.KeyCode == Keys.ControlKey)
                    m_fOkToUpdateAutoComplete = false;
                else
                    m_fOkToUpdateAutoComplete = true;
            }
            catch (Exception)
            {
            }
        }
        ConcurrentBag<Task> tasks = new ConcurrentBag<Task>();
        CancellationTokenSource tokenSource = new CancellationTokenSource();
        private IList<CancellationTokenSource> tokenSources = new List<CancellationTokenSource>();
        private void cmbSearch_KeyUp(object sender, KeyEventArgs e)
        {
            try
            {
                if (e.KeyCode == Keys.Up || e.KeyCode == Keys.Down)
                {
                    isKeyDownOrKeyUp = true;
                }
                else
                {
                    isKeyDownOrKeyUp = false;
                }
                if (m_fOkToUpdateAutoComplete)
                {
                    if (tokenSources.Count > 0)
                    {
                        foreach (var cancellationTokenSource in tokenSources)
                        {
                            if (!cancellationTokenSource.IsCancellationRequested)
                            {
                                cancellationTokenSource.Cancel();
                            }
                        }
                    }
                    tokenSource = new CancellationTokenSource();
                    var token = tokenSource.Token;
                    if (!string.IsNullOrEmpty(cmbSearch.Text))
                    {
                        Task t;
                        t = Task.Factory.StartNew(() => InvokeApi(token), token);
                        tasks.Add(t);
                        tokenSources.Add(tokenSource);
                    }
                    else
                    {
                        cmbSearch.DroppedDown = false;
                        cmbSearch.DataSource = null;
                        ClearControls();
                    }
                }
            }
            catch (Exception ex)
            {
                // MessageBox.Show(ex.Message);
            }
        }
        private void InvokeApi(CancellationToken ct)
        {
            try
            {
                var _with1 = cmbSearch;
                m_sLastSearchedFor = _with1.Text;
                this.UseWaitCursor = true;
                // Was cancellation already requested?  
                if (ct.IsCancellationRequested == true)
                {
                    ct.ThrowIfCancellationRequested();
                }
                var search = CapturePlus.Find(m_sLastSearchedFor, "").ToList();
                //search.Insert(0, new MatchingAddress() {AddressId=string.Empty,Criteria=string.Empty,Text=string.Empty });
                // Was cancellation already requested?  
                if (ct.IsCancellationRequested == true)
                {
                    ct.ThrowIfCancellationRequested();
                }
                this.UseWaitCursor = false;
                if (search.Count > 0)
                {
                    cmbSearch.DataSource = search;
                    cmbSearch.DisplayMember = "Text";
                    cmbSearch.ValueMember = "IdAndCrieria";
                    cmbSearch.DroppedDown = true;
                    cmbSearch.SelectedIndex = -1;
                    cmbSearch.Text = m_sLastSearchedFor;
                    cmbSearch.SelectionStart = cmbSearch.Text.Length;
                    cmbSearch.AutoCompleteMode = AutoCompleteMode.None;
                }
                else
                {
                    cmbSearch.DroppedDown = false;
                    cmbSearch.DataSource = null;
                    cmbSearch.Text = m_sLastSearchedFor;
                    cmbSearch.SelectionStart = cmbSearch.Text.Length;
                    ClearControls();
                }
            }
            catch (OperationCanceledException can)
            {
                this.UseWaitCursor = false;
                cmbSearch.DroppedDown = false;
                cmbSearch.DataSource = null;
                cmbSearch.Text = m_sLastSearchedFor;
                cmbSearch.SelectionStart = cmbSearch.Text.Length;
                ClearControls();
            }
            catch (Exception e)
            {
                this.UseWaitCursor = false;
            }
        }
        private void cmbSearch_SelectedIndexChanged(object sender, EventArgs e)
        {
            try
            {
                if (cmbSearch.SelectedIndex >= -1)
                {
                    if (isKeyDownOrKeyUp)
                        return; // Disable selection on KeyUp and Keydown.
                    var id = "";
                    var criteria = "";
                    var selectedValue = cmbSearch.SelectedValue;
                    if (selectedValue != null)
                    {
                        char[] separator = new char[] { '_' };
                        string[] split = selectedValue.ToString().Split(separator);
                        if (split != null && split.Length > 1)
                        {
                            id = split[0];
                            criteria = split[1];
                        }
                    }
                    if (id != null || criteria != null)
                    {
                        if (criteria == "Find")
                        {
                            _retrieved = false;

                            var findAddressWithId = CapturePlus.Find(m_sLastSearchedFor, id).ToList();
                            if (findAddressWithId.Count > 0)
                            {
                                cmbSearch.DataSource = findAddressWithId;
                                cmbSearch.DisplayMember = "Text";
                                cmbSearch.ValueMember = "IdAndCrieria";
                                cmbSearch.DroppedDown = true;
                                cmbSearch.Text = m_sLastSearchedFor;
                                cmbSearch.SelectionStart = cmbSearch.Text.Length;
                                cmbSearch.SelectedIndex = -1;
                                ClearControls();
                            }
                            else
                            {
                                cmbSearch.DroppedDown = false;
                            }
                        }
                        else
                        {
                            ClearControls();
                        }
                        if (criteria == "Retrieve")
                        {
                            var retriveAddress = CapturePlus.Retrieve(id).ToList();
                            try
                            {
                                if (retriveAddress.Any())
                                {
                                    _selectedAddress = retriveAddress.ToArray()[0];
                                    BindDetails(_selectedAddress);
                                    SetAddressToDisplay();
                                    _retrieved = true;
                                }
                                else
                                {
                                    ClearControls();
                                }
                            }
                            catch (Exception)
                            {
                                // Log exception.
                            }
                        }
                        else
                        {
                            //cmbSearch.DataSource = null;
                            ClearControls();
                        }
                    }
                }
                else
                {
                    cmbSearch.DataSource = null;
                    cmbSearch.DroppedDown = false;
                    ClearControls();
                }
            }
            catch (Exception ex)
            {
                //MessageBox.Show(ex.Message);
            }
        }

上面的代码没有按预期工作。

主要问题是

1)。当我使用组合框时，当用户输入第一个项目时，默认情况下会被选中。2).当我将数据源设置为null时，用户的输入正在刷新，这有点令人困惑。3).使用上下箭头在导航列表中选择项目。当选择发生变化时，我们调用API来再次刷新列表。因此，用户无法浏览其他项目。

我认为我没有完全解释清楚，对大多数用户来说可能没有任何意义。对不起。

请告诉我，如果已经有一些自定义控件，可以用来分配动态数据源或一种文本框，它采取输入并显示在组合框样式的列表。