VB & C# .NET/WinForms: Language Selector ComboBox

vblover Programmer

3.12/5 (6 votes)

Jan 14, 2023

CPOL

1 min read

8954

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Custom DropDownBox with all languages of the world to select a language.Save and reload Selected language using Application Settings

Introduction

This custom component can be used, to select a language for user profile by Application user or else.

Background

Use GetCultures function of CultureInfo class to Load All Languages by choosing CultureTypes.AllCultures for types argument.

 For Each Item As CultureInfo In CultureInfo.GetCultures(CultureTypes.AllCultures)
  If Item.LCID = 127 Then Continue For
   Me.Items.Add(Item)
 Next

foreach (CultureInfo culture in CultureInfo.GetCultures(CultureTypes.AllCultures))
 {
  if (culture.LCID == 127) { continue; }
  this.Items.Add(culture);
 }

Using the Code

Namespaces

System.Windows.Forms
System.ComponentModel
System.Globalization
System.Drawing

Steps

Create a new class with inheritance of ComboBox class.
Set the class name to LanguageSelectorComboBox.

Public Class LanguageSelectorComboBox
    Inherits ComboBox
    
End Class

class LanguageSelectorComboBox:ComboBox
    { }

Create an Enumeration with DisplayValues name for LanguageSelectorComboBox class:

Enum DisplayValues
    DisplayName = 0
    Name = 1
    NativeName = 2
    EnglishName = 3
End Enum

public enum DisplayValues
 {
    DisplayName = 0,
    Name = 1,
    NativeName = 2,
    EnglishName = 3
 }

Create DisplayValue property for the class:

    Private DisplayValueValue As DisplayValues
    <RefreshProperties(RefreshProperties.All)>
    <DefaultValue(0)>    
    Public Property DisplayValue() As DisplayValues
        Get
            Return DisplayValueValue
        End Get
        Set(ByVal value As DisplayValues)
            DisplayValueValue = value
        End Set
    End Property

    private DisplayValues DisplayValueValue;
    [DefaultValue(0)]
    public DisplayValues DisplayValue
    {
        get { return DisplayValueValue; }
        set { DisplayValueValue = value; }
    }

Create SelectedItem property with CultureInfo type as Shadow property.
This property uses SelectedItem property of Base Class to set and return Value:

    Public Shadows Property SelectedItem() As CultureInfo
        Get
            Return MyBase.SelectedItem
        End Get
        Set(ByVal value As CultureInfo)
            MyBase.SelectedItem = value
        End Set
    End Property

public new CultureInfo SelectedItem
 {
    get { return (CultureInfo)base.SelectedItem; } 
    set {  base.SelectedItem = value; }
 }

Create SelectedValue property with Integer Type as Shadow property:
This property uses GetCultureInfo function of CultureInfo class to set SelectedItem property of the Class and take LCID of SelectedItem as return Value:

Public Shadows Property SelectedValue() As Integer
 Get
  If Me.SelectedItem Is Nothing Then Return CultureInfo.CurrentCulture.LCID
  Return Me.SelectedItem.LCID
 End Get
 Set(ByVal value As Integer)
  Me.SelectedItem = CultureInfo.GetCultureInfo(value)
 End Set
End Property

public new int SelectedValue
  {
   get
   {
    if (this.SelectedItem == null)
      {return CultureInfo.CurrentCulture.LCID;}
      else
      {return this.SelectedItem.LCID;}
   }   
   set 
   {
    this.SelectedItem = CultureInfo.GetCultureInfo(value)
   }
  }

Use InitLayout overridable method to set Default Values of Properties as below:

Protected Overrides Sub InitLayout()
 MyBase.InitLayout()
  If Me.DesignMode = True Then Exit Sub
   Me.Items.Clear()
   Me.DrawMode = DrawMode.OwnerDrawFixed
   Me.DropDownStyle = ComboBoxStyle.DropDownList
   Me.Sorted = True
   For Each Item As CultureInfo _
       In CultureInfo.GetCultures(CultureTypes.AllCultures)
     If Item.LCID = 127 Then Continue For
      Me.Items.Add(Item)
   Next
   If Me.Items.Count > 0 Then
      Me.SelectedItem = CultureInfo.CurrentCulture
   End If
  End Sub

protected override void InitLayout()
{
 base.InitLayout();
 if (this.DesignMode == true)
  {
    return;               
  }
  this.DropDownStyle = ComboBoxStyle.DropDownList;
  this.DrawMode = DrawMode.OwnerDrawFixed;
  this.Sorted = true;
  this.Items.Clear();
  foreach (CultureInfo culture in 
           CultureInfo.GetCultures(CultureTypes.AllCultures))
   {
    if (culture.LCID == 127) { continue; }
     this.Items.Add(culture);
    }
   if (base.Items.Count > 0)
     {
      this.SelectedItem = CultureInfo.CurrentCulture;
     }
    }

Using OnDrawItem overridable method to Draw the DisplayValue:

Protected Overrides Sub OnDrawItem(e As DrawItemEventArgs)
    MyBase.OnDrawItem(e)
    If e.Index = -1 Then Exit Sub
    Dim Expr As String = ""
    e.DrawBackground()
    Dim g As Graphics = e.Graphics
    With DirectCast(Me.Items(e.Index), CultureInfo)
        Select Case Me.DisplayValue
            Case DisplayValues.DisplayName
                Expr = .DisplayName
            Case DisplayValues.Name
                Expr = .Name
            Case DisplayValues.NativeName
                Expr = .NativeName
            Case DisplayValues.EnglishName
                Expr = .EnglishName
        End Select
    End With
    g.DrawString(Expr, e.Font, New SolidBrush(e.ForeColor), e.Bounds)
End Sub

protected override void OnDrawItem(DrawItemEventArgs e)
{
    base.OnDrawItem(e);
    if (e.Index==-1) { return; }
    string Expr = string.Empty;
    CultureInfo Culture = (CultureInfo)this.Items[e.Index];
    switch (DisplayValue)
        {
        case DisplayValues.DisplayName:
            Expr = Culture.DisplayName; 
            break;
        case DisplayValues.EnglishName:
            Expr = Culture.DisplayName; 
            break;
        case DisplayValues.Name:
            Expr = Culture.Name;
            break;
        case DisplayValues.NativeName:
            Expr = Culture.NativeName;
            break;
        }
    Graphics g = e.Graphics;
    e.DrawBackground();
    g.DrawString(Expr, e.Font, new SolidBrush(e.ForeColor), e.Bounds);
}

After these steps, build the project and go to Toolbox, then choose LanguageSelectorComboBox item and drop that on the project MainForm:

Go to Application Properties -> Settings Tab-page and create

SelectedLanguage As System.Globalization.CultureInfo
SelectedValue As Integer

Settings for Application Settings

To set Application Settings, use these code lines:

Private Sub button1_Click(sender As Object, e As EventArgs) Handles button1.Click
    My.Settings.SelectedLanguage = Me.LanguageSelectorComboBox1.SelectedItem
    My.Settings.SelectedValue = Me.LanguageSelectorComboBox1.SelectedValue
    My.Settings.Save()
End Sub

private Properties.Settings Settings = Properties.Settings.Default;
private void button1_Click(object sender, EventArgs e)
 {
    Settings.SelectedLanguage = languageSelectorComboBox1.SelectedItem;
    Settings.SelectedValue = languageSelectorComboBox1.SelectedValue;
    Settings.Save();
 }

To Reload SelectedItem:

Private Sub button2_Click(sender As Object, e As EventArgs) Handles button2.Click
    Me.LanguageSelectorComboBox1.SelectedItem = My.Settings.SelectedLanguage
End Sub

private void button2_Click(object sender, EventArgs e)
{
    languageSelectorComboBox1.SelectedItem = Settings.SelectedLanguage;
}

And to Reload SelectedValue:

Private Sub button3_Click(sender As Object, e As EventArgs) Handles button3.Click
    Me.LanguageSelectorComboBox1.SelectedValue = My.Settings.SelectedValue
End Sub

private void button3_Click(object sender, EventArgs e)
{
    languageSelectorComboBox1.SelectedValue = Settings.SelectedValue;
}

History

Friday, 13^th January, 2023: Initial version