How to Dynamically Change Auto Complete Entries in a C# Combobox or Textbox

C# winforms combobox dynamic autocomplete

Here is my final solution. It works fine with a large amount of data. I use Timer to make sure the user want find current value. It looks like complex but it doesn't.
Thanks to Max Lambertini for the idea.

        private bool _canUpdate = true; 

        private bool _needUpdate = false;       

        //If text has been changed then start timer
        //If the user doesn't change text while the timer runs then start search
        private void combobox1_TextChanged(object sender, EventArgs e)
        {
            if (_needUpdate)
            {
                if (_canUpdate)
                {
                    _canUpdate = false;
                    UpdateData();                   
                }
                else
                {
                    RestartTimer();
                }
            }
        }

        private void UpdateData()
        {
            if (combobox1.Text.Length > 1)
            {
                List<string> searchData = Search.GetData(combobox1.Text);
                HandleTextChanged(searchData);
            }
        }       

        //If an item was selected don't start new search
        private void combobox1_SelectedIndexChanged(object sender, EventArgs e)
        {
            _needUpdate = false;
        }

        //Update data only when the user (not program) change something
        private void combobox1_TextUpdate(object sender, EventArgs e)
        {
            _needUpdate = true;
        }

        //While timer is running don't start search
        //timer1.Interval = 1500;
        private void RestartTimer()
        {
            timer1.Stop();
            _canUpdate = false;
            timer1.Start();
        }

        //Update data when timer stops
        private void timer1_Tick(object sender, EventArgs e)
        {
            _canUpdate = true;
            timer1.Stop();
            UpdateData();
        }

        //Update combobox with new data
        private void HandleTextChanged(List<string> dataSource)
        {
            var text = combobox1.Text;

            if (dataSource.Count() > 0)
            {
                combobox1.DataSource = dataSource;  

                var sText = combobox1.Items[0].ToString();
                combobox1.SelectionStart = text.Length;
                combobox1.SelectionLength = sText.Length - text.Length;
                combobox1.DroppedDown = true;

                return;
            }
            else
            {
                combobox1.DroppedDown = false;
                combobox1.SelectionStart = text.Length;
            }
        }

This solution isn't very cool. So if someone has another solution please share it with me.

Auto Complete feature in C# win forms dynamic

You can config a TextBox to use a custom source for auto complete:

• Set AutoCompleteMode property of a TextBox to Suggest, Append or SuggestAppend
• Set AutoCompleteSource property to CustomSource.
• Assign a custom source to AutoCompleteCustomSource property of TextBox.

Example

In the below example, I set list of month names as auto complete source. You can use any string[] as auto complete custom source.

textBox1.AutoCompleteMode = AutoCompleteMode.Suggest;
textBox1.AutoCompleteSource = AutoCompleteSource.CustomSource;
var source = new AutoCompleteStringCollection();
source.AddRange(System.Globalization.CultureInfo
                      .InvariantCulture.DateTimeFormat.MonthNames);
textBox1.AutoCompleteCustomSource = source;

How to create an Auto-complete combo-box or text box to filter text containing a string

If you mean show suggestions then it's a simple matter of changing a property when you have the TextBox selected in your IDE of choice:

The options shown in the picture allow you to change the rules for autocompleting text in the text box as well as the source for the suggestions. (Visual Studio 2010)

You can go to the following link to learn more about the TextBox control.

MSDN Text Box Control

How to use auto-complete TextBox or a ComboBox in webform

The equivalent control for a ComboBox in ASP.Net is the DropDownList. You can use JQuery for autocomplete style functionality. See this link: http://jqueryui.com/autocomplete/#combobox.

Change the auto-complete behaviour of a textbox

I assume you're asking about a winforms textbox, as I dont think the WPF textbox supports autocomplete at all.

The base TextBox class will not support doing what you want, so you could in theory attempt to override all of the functionality in the TextBox class to do what you want, but the better idea would be to create a new custom control that inherits from TextBoxBase and implement the autocomplete behavior the way you want it.

change comboBox to Auto Complete Text Field codename one

You don't need a renderer since the model would return strings which is what you need for the auto complete to work.

You need to convert your code so your model is a list of strings and then just place an auto complete with that.

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