How can I Customize a TextBox for AutoCompletiton with items separated by Comma?

C#

private void AutoComplete1_AutoCompleteItemSelected(object sender, Syncfusion.Windows.Forms.Tools.AutoCompleteItemEventArgs args)

{

Control ct = this.TextBox1;

if (this.AutoComplete1.ActiveFocusControl == ct)

{

int commaPos = this.TextBox1.Text.LastIndexOf(",");

string currentText = this.TextBox1.Text;

if (commaPos >= 0)

{

currentText = this.TextBox1.Text.Substring(0, commaPos + 1);

}

args.SelectedValue = currentText + args.ItemArray[args.MatchColumnIndex].ToString();

args.Handled = true;

}

}

private void AutoComplete1_AutoCompleteCustomize(object sender, Syncfusion.Windows.Forms.Tools.AutoCompleteCustomizeEventArgs args)

{

Control ct = this.TextBox1;

if (args.ActiveFocusControl == ct)

{

int commaPos = this.TextBox1.Text.LastIndexOf(",");

string commaText = "";

if (commaPos >= 0)

{

commaText = this.TextBox1.Text.Substring(commaPos + 1, this.TextBox1.TextLength - commaPos - 1);

}

if (this.TextBox1.SelectionStart > commaPos & commaPos >= 0)

{

args.AutoSuggestLocation = new Point(this.Location.X + this.TextBox1.Location.X + (this.TextBox1.TextLength * 5) + 2, this.Location.Y + 40 + this.TextBox1.Location.Y + 10);

args.TextForAutoCompletion = commaText;

args.Handled = true;

}

}

}