How to select a item on rightclick using devexpress ListboxControl

To select a item on rightclick using devexpress ListboxControl you need to use the MouseDown Event.
See the samples below.

Sample C#

private void listBoxControl1_MouseDown(object sender, MouseEventArgs e)
{
	listBoxControl1.SelectedIndex = listBoxControl1.IndexFromPoint(new Point(e.X, e.Y));
}

Sample VB.NET

Private Sub listBoxControl1_MouseDown(sender As Object, e As MouseEventArgs)
	listBoxControl1.SelectedIndex = listBoxControl1.IndexFromPoint(New Point(e.X, e.Y))
End Sub

How to Display an Image in Devexpress XtraGrid Control using C# and VB.NET

To Display an Image in Devexpress XtraGrid Control using C# and VB.NET see the example below.

Sample C#

#region

using System.Data;
using System.Drawing;
using System.Windows.Forms;
using WindowsFormsApplication77.Properties;
using DevExpress.XtraEditors.Repository;

#endregion

namespace de.fesslersoft.XtraGridImageTest
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
            gridControl1.DataSource = CreateTable(3);
            gridView1.Columns["Image"].ColumnEdit = new RepositoryItemPictureEdit();
        }

        private DataTable CreateTable(int rowCount)
        {
            var image = Resources.Image1;
            var tbl = new DataTable();
            tbl.Columns.Add("ID", typeof (int));
            tbl.Columns.Add("URL", typeof (string));
            tbl.Columns.Add("Image", typeof (Image));
            for (var i = 0; i < rowCount; i++)
            {
                tbl.Rows.Add(new object[] {i, "http://codesnippets.fesslersoft.de", image});
            }
            return tbl;
        }
    }
}

Sample VB.NET

#Region ""

Imports System.Data
Imports System.Drawing
Imports System.Windows.Forms
Imports WindowsFormsApplication77.Properties
Imports DevExpress.XtraEditors.Repository

#End Region

Namespace de.fesslersoft.XtraGridImageTest
	Public Partial Class Form1
		Inherits Form
		Public Sub New()
			InitializeComponent()
			gridControl1.DataSource = CreateTable(3)
			gridView1.Columns("Image").ColumnEdit = New RepositoryItemPictureEdit()
		End Sub

		Private Function CreateTable(rowCount As Integer) As DataTable
			Dim image = Resources.Image1
			Dim tbl = New DataTable()
			tbl.Columns.Add("ID", GetType(Integer))
			tbl.Columns.Add("URL", GetType(String))
			tbl.Columns.Add("Image", GetType(Image))
			For i As var = 0 To rowCount - 1
				tbl.Rows.Add(New Object() {i, "http://codesnippets.fesslersoft.de", image})
			Next
			Return tbl
		End Function
	End Class
End Namespace

Result

XtraGrid ColumnImages

XtraGrid ColumnImages


How to make a multicolumn listbox in C# and VB.NET

To make a multicolumn listbox in C# and VB.NET you can use the following snippet.
First you need to add the Columns to the Listview.

multicolumnslistviewcsharp_add

Adding columns to the Listview

Sample C#

listView1.Items.Add("Column1Text").SubItems.AddRange(new string[] { "col1;row1", "col2;row1", "col3;row1" });
listView1.Items.Add("Column2Text").SubItems.AddRange(new string[] { "col1;row2", "col2;row2", "col3;row2" });
listView1.Items.Add("Column3Text").SubItems.AddRange(new string[] { "col1;row3", "col2;row3", "col3;row3" });

Sample VB.NET

listView1.Items.Add("Column1Text").SubItems.AddRange(New String() {"col1;row1", "col2;row1", "col3;row1"})
listView1.Items.Add("Column2Text").SubItems.AddRange(New String() {"col1;row2", "col2;row2", "col3;row2"})
listView1.Items.Add("Column3Text").SubItems.AddRange(New String() {"col1;row3", "col2;row3", "col3;row3"})
multicolumnslistviewcsharp

Result: Listview with Multiple Columns

How to check if a Form is Open in C# and VB.NET

To Check if a Form is open in C# and VB.NET you can use the snippet below.

Sample C#

public static bool FormIsOpen(FormCollection application, Type formType)
{
	//usage sample: FormIsOpen(Application.OpenForms,typeof(Form2)
	return Application.OpenForms.Cast<Form>().Any(openForm => openForm.GetType() == formType);
}

Sample VB.NET

Public Shared Function FormIsOpen(application__1 As FormCollection, formType As Type) As Boolean
	'usage sample: FormIsOpen(Application.OpenForms,GetType(Form2)
	Return Application.OpenForms.Cast(Of Form)().Any(Function(openForm) openForm.[GetType]() = formType)
End Function

How to change Checkstate of an item in a checkedlistbox control in C# or VB.NET

To change the Checkstate of an item in a checkedlistbox control in C# or VB.NET you can use the SetItemCheckState method of the checkedlistbox control.

Sample C#

private void ChangeCheckStateForAllCheckBoxes(bool check) {
    for (int i = 0; i <= (checkedListBox1.Items.Count - 1); i++) {
        if (check)
        {
            checkedListBox1.SetItemCheckState(i, CheckState.Checked);
        }
        else
        {
            checkedListBox1.SetItemCheckState(i, CheckState.Unchecked);
        }
    }  
}

Sample VB.NET

Private Sub ChangeCheckStateForAllCheckBoxes(check As Boolean)
	For i As Integer = 0 To (checkedListBox1.Items.Count - 1)
		If check Then
			checkedListBox1.SetItemCheckState(i, CheckState.Checked)
		Else
			checkedListBox1.SetItemCheckState(i, CheckState.Unchecked)
		End If
	Next
End Sub

for more informations see CheckedListBox.ObjectCollection Class, CheckedListBox.SetItemChecked Method