VB .NET - Exibindo as bandeiras dos países a partir do nome
 Neste artigo vou mostrar como podemos usar o arquivo de recursos para exibir a bandeira de um país selecionado usando a linguagem VB .NET.

Ao utilizar imagens e arquivos texto em sua aplicação .NET pode ser mais conveniente embutir estas imagens e arquivos como resources(recursos) no seu projeto, ao invés de deixar as imagens e arquivos texto como arquivos separados e depois tentar localizar e carregar as imagens do disco quando a aplicação estiver em execução.

Neste artigo vamos armazenar imagens dos países em um arquivo de recurso e definir uma classe que herda de Dictionary para recuperar a imagem da bandeira dado o nome do país.

Recursos usados :

Criando o projeto no VS Community

Abra o VS Community 2015  e clique em New Project;

A seguir selecione Visual Basic -> Windows -> Windows Forms Application;

Informe o nome Paises_Bandeiras e clique no botão OK;

A partir da ToolBox inclua os seguintes controles no formulário form1.vb:

Disponha os controles conforme o leiaute da figura abaixo:

No menu PROJECT clique em Add Class e informe o nome Bandeiras;

A seguir vamos definir esta classe como herdando da classe Dictionary.

A classe Dictionary representa uma coleção de chaves e valores. É uma coleção do tipo chave/valor e implementa  a interface IDictionary que possui duas coleções no seu interior uma para guardar a chave e outra para guardar o valor.

Para no nosso caso o dicionário irá possuir uma coleção de strings e imagens. Então no construtor da classe Bandeiras defina o código abaixo:

Public Class Bandeiras
    Inherits Dictionary(Of String, Image)
    Public Sub New()
        Me.Add("Afghanistan", My.Resources.Afghanistan)
        Me.Add("Albania", My.Resources.Albania)
        Me.Add("Algeria", My.Resources.Algeria)
        Me.Add("American Samoa", My.Resources.American_Samoa)
        Me.Add("Andorra", My.Resources.Andorra)
        Me.Add("Angola", My.Resources.Angola)
        Me.Add("Anguilla", My.Resources.Anguilla)
        Me.Add("Antigua and Barbuda", My.Resources.Antigua_and_Barbuda)
        Me.Add("Argentina", My.Resources.Argentina)
        Me.Add("Armenia", My.Resources.Armenia)
        Me.Add("Aruba", My.Resources.Aruba)
        Me.Add("Australia", My.Resources.Australia)
        Me.Add("Austria", My.Resources.Austria)
        Me.Add("Azerbaijan", My.Resources.Azerbaijan)
        Me.Add("Bahamas", My.Resources.Bahamas)
        Me.Add("Bahrain", My.Resources.Bahrain)
        Me.Add("Bangladesh", My.Resources.Bangladesh)
        Me.Add("Barbados", My.Resources.Barbados)
        Me.Add("Belarus", My.Resources.Belarus)
        Me.Add("Belgium", My.Resources.Belgium)
        Me.Add("Belize", My.Resources.Belize)
        Me.Add("Benin", My.Resources.Benin)
        Me.Add("Bermuda", My.Resources.Bermuda)
        Me.Add("Bhutan", My.Resources.Bhutan)
        Me.Add("Bolivia", My.Resources.Bolivia)
        Me.Add("Bosnia", My.Resources.Bosnia)
        Me.Add("Botswana", My.Resources.Botswana)
        Me.Add("Brazil", My.Resources.Brazil)
        Me.Add("British Virgin Islands", My.Resources.British_Virgin_Islands)
        Me.Add("Brunei", My.Resources.Brunei)
        Me.Add("Bulgaria", My.Resources.Bulgaria)
        Me.Add("Burkina Faso", My.Resources.Burkina_Faso)
        Me.Add("Burundi", My.Resources.Burundi)
        Me.Add("Cambodia", My.Resources.Cambodia)
        Me.Add("Cameroon", My.Resources.Cameroon)
        Me.Add("Canada", My.Resources.Canada)
        Me.Add("Cape Verde", My.Resources.Cape_Verde)
        Me.Add("Cayman Islands", My.Resources.Cayman_Islands)
        Me.Add("Central African Republic", My.Resources.Central_African_Republic)
        Me.Add("Chad", My.Resources.Chad)
        Me.Add("Chile", My.Resources.Chile)
        Me.Add("China", My.Resources.China)
        Me.Add("Christmas Islands", My.Resources.Christmas_Island)
        Me.Add("Colombia", My.Resources.Colombia)
        Me.Add("Comoros", My.Resources.Comoros)
        Me.Add("Cook Islands", My.Resources.Cook_Islands)
        Me.Add("Costa Rica", My.Resources.Costa_Rica)
        Me.Add("Croatia", My.Resources.Croatia)
        Me.Add("Cuba", My.Resources.Cuba)
        Me.Add("Cyprus", My.Resources.Cyprus)
        Me.Add("Czech Republic", My.Resources.Czech_Republic)
        Me.Add("Democratic Republic of the Congo", My.Resources.Democratic_Republic_of_the_Congo)
        Me.Add("East Timor", My.Resources.East_Timor)
        Me.Add("Ecuador", My.Resources.Ecuador)
        Me.Add("Egypt", My.Resources.Egypt)
        Me.Add("El Salvador", My.Resources.El_Salvador)
        Me.Add("Equatorial Guinea", My.Resources.Equatorial_Guinea)
        Me.Add("Eritrea", My.Resources.Eritrea)
        Me.Add("Estonia", My.Resources.Estonia)
        Me.Add("Ethiopia", My.Resources.Ethiopia)
        Me.Add("Falkland Islands", My.Resources.Falkland_Islands)
        Me.Add("Faroe Islands", My.Resources.Faroe_Islands)
        Me.Add("Fiji", My.Resources.Fiji)
        Me.Add("Finland", My.Resources.Finland)
        Me.Add("France", My.Resources.France)
        Me.Add("French Polynesia", My.Resources.French_Polynesia)
        Me.Add("Gabon", My.Resources.Gabon)
        Me.Add("Gambia", My.Resources.Gambia)
        Me.Add("Georgia", My.Resources.Georgia)
        Me.Add("Germany", My.Resources.Germany)
        Me.Add("Ghana", My.Resources.Ghana)
        Me.Add("Gibraltar", My.Resources.Gibraltar)
        Me.Add("Greece", My.Resources.Greece)
        Me.Add("Greenland", My.Resources.Greenland)
        Me.Add("Grenada", My.Resources.Grenada)
        Me.Add("Guam", My.Resources.Guam)
        Me.Add("Guatemala", My.Resources.Guatemala)
        Me.Add("Guinea", My.Resources.Guinea)
        Me.Add("Guinea Bissau", My.Resources.Guinea_Bissau)
        Me.Add("Guyana", My.Resources.Guyana)
        Me.Add("Haiti", My.Resources.Haiti)
        Me.Add("Honduras", My.Resources.Honduras)
        Me.Add("Hong Kong", My.Resources.Hong_Kong)
        Me.Add("Hungary", My.Resources.Hungary)
        Me.Add("Iceland", My.Resources.Iceland)
        Me.Add("India", My.Resources.India)
        Me.Add("Indonesia", My.Resources.Indonesia)
        Me.Add("Iran", My.Resources.Iran)
        Me.Add("Iraq", My.Resources.Iraq)
        Me.Add("Ireland", My.Resources.Ireland)
        Me.Add("Israel", My.Resources.Israel)
        Me.Add("Italy", My.Resources.Italy)
        Me.Add("Ivory Coast", My.Resources.Ivory_Coast)
        Me.Add("Jamaica", My.Resources.Jamaica)
        Me.Add("Japan", My.Resources.Japan)
        Me.Add("Jordan", My.Resources.Jordan)
        Me.Add("Kazakhstan", My.Resources.Kazakhstan)
        Me.Add("Kenya", My.Resources.Kenya)
        Me.Add("Kiribati", My.Resources.Kiribati)
        Me.Add("Kuwait", My.Resources.Kuwait)
        Me.Add("Kyrgyzstan", My.Resources.Kyrgyzstan)
        Me.Add("Laos", My.Resources.Laos)
        Me.Add("Latvia", My.Resources.Latvia)
        Me.Add("Lebanon", My.Resources.Lebanon)
        Me.Add("Lesotho", My.Resources.Lesotho)
        Me.Add("Liberia", My.Resources.Liberia)
        Me.Add("Libya", My.Resources.Libya)
        Me.Add("Liechtenstein", My.Resources.Liechtenstein)
        Me.Add("Lithuania", My.Resources.Lithuania)
        Me.Add("Luxembourg", My.Resources.Luxembourg)
        Me.Add("Macao", My.Resources.Macao)
        Me.Add("Macedonia", My.Resources.Macedonia)
        Me.Add("Madagascar", My.Resources.Madagascar)
        Me.Add("Malawi", My.Resources.Malawi)
        Me.Add("Malaysia", My.Resources.Malaysia)
        Me.Add("Maldives", My.Resources.Maldives)
        Me.Add("Mali", My.Resources.Mali)
        Me.Add("Malta", My.Resources.Malta)
        Me.Add("Marshall Islands", My.Resources.Marshall_Islands)
        Me.Add("Martinique", My.Resources.Martinique)
        Me.Add("Mauritania", My.Resources.Mauritania)
        Me.Add("Mexico", My.Resources.Mexico)
        Me.Add("Micronesia", My.Resources.Micronesia)
        Me.Add("Moldova", My.Resources.Moldova)
        Me.Add("Monaco", My.Resources.Monaco)
        Me.Add("Mongolia", My.Resources.Mongolia)
        Me.Add("Montserrat", My.Resources.Montserrat)
        Me.Add("Morocoo", My.Resources.Morocco)
        Me.Add("Mozambique", My.Resources.Mozambique)
        Me.Add("Myanmar", My.Resources.Myanmar)
        Me.Add("Namibia", My.Resources.Namibia)
        Me.Add("Nauru", My.Resources.Nauru)
        Me.Add("Nepal", My.Resources.Nepal)
        Me.Add("Netherlands", My.Resources.Netherlands)
        Me.Add("Netherlands Antilles", My.Resources.Netherlands_Antilles)
        Me.Add("New Zealand", My.Resources.New_Zealand)
        Me.Add("Nicaragua", My.Resources.Nicaragua)
        Me.Add("Niger", My.Resources.Niger)
        Me.Add("Nigeria", My.Resources.Nigeria)
        Me.Add("Niue", My.Resources.Niue)
        Me.Add("Norfolk Island", My.Resources.Norfolk_Island)
        Me.Add("North Korea", My.Resources.North_Korea)
        Me.Add("Norway", My.Resources.Norway)
        Me.Add("Oman", My.Resources.Oman)
        Me.Add("Pakistan", My.Resources.Pakistan)
        Me.Add("Palau", My.Resources.Palau)
        Me.Add("Panama", My.Resources.Panama)
        Me.Add("Papua New Guinea", My.Resources.Papua_New_Guinea)
        Me.Add("Paraguay", My.Resources.Paraguay)
        Me.Add("Peru", My.Resources.Peru)
        Me.Add("Philippines", My.Resources.Philippines)
        Me.Add("Pitcairn Islands", My.Resources.Pitcairn_Islands)
        Me.Add("Poland", My.Resources.Poland)
        Me.Add("Portugal", My.Resources.Portugal)
        Me.Add("Puerto Rico", My.Resources.Puerto_Rico)
        Me.Add("Qatar", My.Resources.Qatar)
        Me.Add("Republic of the Congo", My.Resources.Republic_of_the_Congo)
        Me.Add("Romania", My.Resources.Romania)
        Me.Add("Russian Federation", My.Resources.Russian_Federation)
        Me.Add("Rwanda", My.Resources.Rwanda)
        Me.Add("Saint Kitts and Nevis", My.Resources.Saint_Kitts_and_Nevis)
        Me.Add("Saint Lucia", My.Resources.Saint_Lucia)
        Me.Add("Saint Pierre", My.Resources.Saint_Pierre)
        Me.Add("Saint Vicent and the Grenadines", My.Resources.Saint_Vicent_and_the_Grenadines)
        Me.Add("Samoa", My.Resources.Samoa)
        Me.Add("Sao Tome and Principe", My.Resources.Sao_Tomé_and_Príncipe)
        Me.Add("Saudi Arabia", My.Resources.Saudi_Arabia)
        Me.Add("Senegal", My.Resources.Senegal)
        Me.Add("Serbia and Montenegro", My.Resources.Serbia_and_Montenegro)
        Me.Add("Seychelles", My.Resources.Seychelles)
        Me.Add("Sierra Leone", My.Resources.Sierra_Leone)
        Me.Add("Singapore", My.Resources.Singapore)
        Me.Add("Slovakia", My.Resources.Slovakia)
        Me.Add("Slovenia", My.Resources.Slovenia)
        Me.Add("Soloman Islands", My.Resources.Soloman_Islands)
        Me.Add("Somalia", My.Resources.Somalia)
        Me.Add("South Africa", My.Resources.South_Africa)
        Me.Add("South Georgia", My.Resources.South_Georgia)
        Me.Add("South Korea", My.Resources.South_Korea)
        Me.Add("Spain", My.Resources.Spain)
        Me.Add("Sri Lanka", My.Resources.Sri_Lanka)
        Me.Add("Sudan", My.Resources.Sudan)
        Me.Add("Suriname", My.Resources.Suriname)
        Me.Add("Swaziland", My.Resources.Swaziland)
        Me.Add("Syria", My.Resources.Syria)
        Me.Add("Taiwan", My.Resources.Taiwan)
        Me.Add("Tajikistan", My.Resources.Tajikistan)
        Me.Add("Tanzania", My.Resources.Tanzania)
        Me.Add("Thailand", My.Resources.Thailand)
        Me.Add("Tibet", My.Resources.Tibet)
        Me.Add("Togo", My.Resources.Togo)
        Me.Add("Tonga", My.Resources.Tonga)
        Me.Add("Trinidad and Tobago", My.Resources.Trinidad_and_Tobago)
        Me.Add("Tunisia", My.Resources.Tunisia)
        Me.Add("Turkey", My.Resources.Turkey)
        Me.Add("Turkmenistan", My.Resources.Turkmenistan)
        Me.Add("Turks and Caicos Islands", My.Resources.Turks_and_Caicos_Islands)
        Me.Add("Tuvalu", My.Resources.Tuvalu)
        Me.Add("UAE", My.Resources.UAE)
        Me.Add("Uganda", My.Resources.Uganda)
        Me.Add("Ukraine", My.Resources.Ukraine)
        Me.Add("United Kingdom", My.Resources.United_Kingdom)
        Me.Add("United States of America", My.Resources.United_States_of_America)
        Me.Add("Uruguay", My.Resources.Uruguay)
        Me.Add("US Virgin Islands", My.Resources.US_Virgin_Islands)
        Me.Add("Uzbekistan", My.Resources.Uzbekistan)
        Me.Add("Vanuatu", My.Resources.Vanuatu)
        Me.Add("Vatican City", My.Resources.Vatican_City)
        Me.Add("Venezuela", My.Resources.Venezuela)
        Me.Add("Vietnam", My.Resources.Vietnam)
        Me.Add("Wallis and Futuna", My.Resources.Wallis_and_Futuna)
        Me.Add("Yemen", My.Resources.Yemen)
        Me.Add("Zambia", My.Resources.Zambia)
        Me.Add("Zimbabwe", My.Resources.Zimbabwe)
    End Sub
End Class

Observe que no código estamos usando My.Recources e o nome do país para indicar a bandeira do país armazenada em um arquivo de recursos.

Nota : Para obter as imagens das bandeiras dos países baixe o arquivo deste link (Bandeiras.zip) e descompacte o arquivo em uma pasta chamada c:\Bandeiras.

O objeto My.Resources fornece acesso aos recursos do aplicativo e permite que você recupere dinamicamente recursos para seu aplicativo. Esse objeto expõe apenas recursos globais e não fornece acesso aos arquivos de recursos associados a formulários. Você deve acessar os recursos de formulário a partir do formulário.

Então nosso próximo passo é criar o arquivo de recursos contendo as imagens das bandeiras dos países.

Clique com o botão direito do mouse sobre o nome do projeto e a seguir clique em Properties;

Na janela de propriedades clique na guia Resources;

A seguir clique em Images e no item Add Resource clique em Add Existing File;

A seguir abra a pasta c:\Bandeiras e selecione todos os arquivos e copie-os para o recurso.

Você deverá obter o seguinte resultado visualizando as bandeiras dos países:

Agora vamos definir o código do formulário para exibir as bandeiras de um determinado país.

Vamos criar uma instância da classe bandeiras que seja visível em todo formulário:

Dim bandeiras As New Bandeiras

A seguir no evento Load do formulário vamos carregar o controle Combobox - cboPaises - com a informação do nome do país a partir da classe Bandeiras:

 Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        For Each key As String In bandeiras.Keys
            cboPaises.Items.Add(key)
        Next
    End Sub

Finalmente vamos usar o evento SelectedIndexChanged do Combobox e incluir o código a seguir

 Private Sub cboPaises_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cboPaises.SelectedIndexChanged
        Dim pais As String = cboPaises.Text
        If bandeiras.ContainsKey(pais) Then
            picBandeira.Image = bandeiras(pais)
            lblPais.Text = pais
        End If
    End Sub

Neste código, havendo qualquer alteração no índice do Combobox estamos obtendo o nome do país (que é a chave do dicionário) e a partir dele obtendo a imagem da classe Bandeiras e exibindo no controle PictureBox - picBandeiras:

Executando o projeto e  selecionando um país da combobox teremos o resultado abaixo:

Pegue o projeto completo aqui :   Paises_Bandeiras.zip (sem os recursos)

Disse-lhe Jesus: Estou há tanto tempo convosco, e não me tendes conhecido, Filipe? Quem me vê a mim vê o Pai; e como dizes tu: Mostra-nos o Pai?
João 14:9

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Referências:

José Carlos Macoratti