TreeView for WinForms | ComponentOne
In This Topic
    In This Topic

    CheckList control displays a collection of items via list box embedded with multiple check boxes (small square shaped selection boxes). It enables multiple selection of items using different states of the check boxes. Additionally, the CheckList control is represented by the C1CheckList class which allows you to perform various operations on the control.

    Add and Remove CheckList Items

    You can access the item collection of CheckList using Items property of the C1CheckList class and add or remove the objects from the list at runtime. To add an item to the CheckList, you can use the Add method.

    This image shows example of CheckList control.

    The following sample code add items from the CheckList control.

    Add CheckList Items
    Copy Code
    // Add all items to the CheckList control
    // Assign names to each Checklist item
    c1CheckListItem1.Value = "Violet";
    c1CheckListItem2.Value = "Indigo";
    c1CheckListItem3.Value = "Blue";
    c1CheckListItem4.Value = "Green";
    c1CheckListItem5.Value = "Yellow";
    c1CheckListItem6.Value = "Orange";
    c1CheckListItem7.Value = "Red";

    To remove specific items from the list, you can use Remove method. The following sample code remove items from the CheckList control.

    Remove CheckList Items
    Copy Code

    Data Binding

    Binding a control with a data source gives you ability to communicate and even update the underlying data through the control. You can bind CheckList using any of the following ways:

    Bind with Database

    You can bind the CheckList to a data source by following these steps:

    1. Create a connection string and fetch data from a database to a data set.
      Copy Code
       static string GetConnectionString()
                  //if process is 32bit use JET.OLEDB otherwise use ACE.OLEDB
                  string provider = "Microsoft.Jet.OLEDB.4.0";
                  if (Environment.Is64BitProcess)
                      provider = "Microsoft.Ace.OLEDB.12.0";
                  string connectionString = $"Provider={provider};Data Source=" +
                           @"ComponentOne Samples\Common\C1NWind.mdb") + ";";
                  return string.Format(connectionString);
              DataTable GetDataSource(string selectStatement)
                  // Set up connection string
                  string conn = GetConnectionString();
                  // Set up SQL statement
                  string rs = selectStatement;
                  // Retrieve data into DataSet
                  OleDbDataAdapter da = new OleDbDataAdapter(rs, conn);
                  DataSet ds = new DataSet();
                  // Return data table
                  return ds.Tables[0];
    2. Set the DataSource and DisplayMemberPath properties of the CheckList control.
      Copy Code
      lCheckList.BindingInfo.DataSource = GetDataSource("Select * from Employees ");
      lCheckList.BindingInfo.DisplayMemberPath = "FirstName";

    After completing the above mentioned steps, you will get the following result.

    Bind DataSource with CheckList

    Bind with Object Collection

    To bind the CheckList control to a list of data objects, follow these steps:

    1. Create a class named Customer using the following code.
      Copy Code
      public class Customer
          string name;
          string customerID;
          string mobile;
          string email;
          public Customer(string _name, string _custId, string _mobile, string _email)
     = _name;
              this.customerID = _custId;
     = _mobile;
     = _email;
          public string Name
                  return name;
          public string CustomerID
                  return customerID;
          public string Mobile
                  return mobile;
          public string Email
                  return email;
    2. Add objects of Customer class to a BindingList and set C1CheckList’s DataSource and DisplayMemberPath properties at Form_Load event.
      Copy Code
      BindingList<Customer> customers = new BindingList<Customer>();
      customers.Add(new Customer("John", "C001", "8888832141", ""));
      customers.Add(new Customer("Alex", "C002", "8888832142", ""));
      customers.Add(new Customer("Shawn", "C003", "8888832143", ""));
      customers.Add(new Customer("Sam", "C004", "8888832144", ""));
      customers.Add(new Customer("Neo", "C005", "8888832145", ""));
      customers.Add(new Customer("Paul", "C006", "8888832146", ""));
      lCheckList.BindingInfo.DataSource = customers;
      lCheckList.BindingInfo.DisplayMemberPath = "Name";

    After completing the above mentioned steps, you get the following result.

    Bind Object Collection with CheckList


    You can select/deselect all items in the list with single selection. To enable this option, you need to set the ShowSelectAll property to true. On setting this property to true, the Select All check box appears on top of the list of items. When you deselect the Select All check box, all items in the list are deselected.

    Set ShowSelectAll property in CheckList

    The following sample code shows how to select/deselect all items in the list.

    Copy Code
    // To show the Select All checkbox
    lCheckList.ShowSelectAll = true;

    In order to display CheckList control with the selected item at initial stage, you can use the following sample code.

    Set item in the initial stage

    Copy Code
    // Make the third item from top appear in the selected state in the CheckList control
    lCheckList.SelectedItem = c1CheckListItem3;

    You can use the SelectionMode property to determine whether a user can select one or more than one item from the header. This property lets you choose between the following selection modes through SelectionMode enumeration:

    Select multiple values in CheckList

    The following sample code shows the method to set the SelectionMode property.

    Copy Code
    // To select multiple items at the same time
    lCheckList.SelectionMode = C1.Win.TreeView.SelectionMode.Multiple;

    Show or Hide CheckBoxes

    You can set the visibility of check boxes in the CheckList control by using ShowCheckBoxes property of the C1CheckList class. The following image displays CheckList items without the check boxes.

    Hide checkboxes in CheckList

    The following sample code sets the visibility of checkbox in the CheckList control.

    Copy Code
    // Hide checkboxes for each CheckList item
    lCheckList.ShowCheckBoxes = false;

    Customize Captions

    You can customize the CheckList control as per your requirements. You can change the captions of Select All option using SelectAllCaption property and the caption of Unselect All option using UnselectAllCaption property of the C1CheckList class.

    Set captions for Select All/ Unselect All option

    The following sample code sets the SelectAllCaption and UnselectAllCaption property of CheckList.

    Copy Code
    lCheckList.ShowCheckBoxes = true;
    lCheckList.SelectAllCaption = "Colors Check All";
    lCheckList.UnselectAllCaption = "Colors UnCheck All";

    Appearance and Style

    CheckList allows you to change the appearance and style of all items in the control. You can use the BorderColor and BorderStyle property to style the border of the CheckList. In addition, you can also set the style of default, selected and hot state of CheckList  control. The following GIF shows the style applied to the CheckList's items.

    Change style of CheckList

    Copy Code
    // Set the color of checkbox
    lCheckList.Styles.CheckBoxColor = Color.Brown;
    // Set the border style
    lCheckList.BorderStyle = BorderStyle.Fixed3D;
    lCheckList.BorderColor = Color.Black;
    // Gets style for the default state of CheckList
    lCheckList.Styles.Default.BackColor = Color.OldLace;
    lCheckList.Styles.Default.ForeColor = Color.Maroon;
    // Gets style for the selected state of CheckList
    lCheckList.Styles.Selected.BackColor = Color.LightYellow;
    lCheckList.Styles.Selected.ForeColor = Color.DeepPink;
    // Gets style for the hot state of CheckList
    lCheckList.Styles.Hot.BackColor = Color.Orange;
    lCheckList.Styles.Hot.ForeColor = Color.LightGray;