逐步解說：使用物件共同地擷取對話方塊資訊

發行項
08/21/2008

更新：2007 年 11 月

大部分的 Windows Form 對話方塊都具有會對父表單公開資訊的屬性。您可以經由建立會儲存父表單所需之全部資訊的類別物件，透過單一對話方塊屬性來公開一群相關的資料，而不需建立多個屬性。

下列逐步解說會建立一個對話方塊，以公開包含了名稱和電子郵件地址資料的 UserInformation 屬性，即使在對話方塊關閉之後，父表單還是可以使用這個屬性。

若要建立透過物件公開其資訊的對話方塊

在 Visual Studio 中，建立稱為 DialogBoxObjects 的新 Windows Form 專案。如需詳細資訊，請參閱 HOW TO：建立 Windows 應用程式專案。
將新的 Form 加入至專案，並將它命名為 InformationForm。如需詳細資訊，請參閱 HOW TO：將 Windows Form 加入至專案。
從 [工具箱] 將 TableLayoutPanel 拖曳到表單上。使用控制項旁邊顯示為箭號圖像的智慧標籤，以便將第三個資料列加入至表格中，然後使用滑鼠調整資料列的大小，讓三個資料列的大小相同。
將 Label 加入至第一個資料行中的每一個表格儲存格，以及將 TextBox 加入至第二個資料行中的每一個儲存格。從上到下分別將 Label 控制項命名為 firstNameLabel、lastNameLabel 和 emailLabel；並且分別將 TextBox 控制項命名為 firstNameText、lastNameText 和 emailText。完成後，再加入一個 Button 控制項，將它命名為 okButton，並將 Text 屬性變更為 OK。
將稱為 UserInformation 的新類別檔加入至專案。
將 public 限定詞加入至類別定義，讓這個類別在它的命名空間外也能被看見，然後加入 FirstName、LastName 和 EmailAddress 屬性的屬性定義。當您完成時，程式碼看起來應該像這樣：

Public Class UserInformation
    Private _FirstName As String = ""
    Private _LastName As String = ""
    Private _EmailAddress As String = ""

    Public Property FirstName() As String
        Get
            Return _FirstName
        End Get
        Set(ByVal value As String)
            _FirstName = value
        End Set
    End Property


    Public Property LastName() As String
        Get
            Return _LastName
        End Get
        Set(ByVal value As String)
            _LastName = value
        End Set
    End Property


    Public Property EmailAddress() As String
        Get
            Return _EmailAddress
        End Get
        Set(ByVal value As String)
            _EmailAddress = value
        End Set
    End Property
End Class

using System;
using System.Collections.Generic;
using System.Text;

namespace DialogBoxObjects
{
    public class UserInformation
    {
        private string _firstName = "";
        private string _lastName = "";
        private string _emailAddress = "";

        public string FirstName
        {
            get
            {
                return (_firstName);
            }
            set
            {
                _firstName = value;
            }
        }

        public string LastName
        {
            get
            {
                return (_lastName);
            }
            set
            {
                _lastName = value;
            }
        }

        public string EmailAddress
        {
            get
            {
                return (_emailAddress);
            }
            set
            {
                _emailAddress = value;
            }
        }
    }
}

using namespace System;
using namespace System::Collections::Generic;
using namespace System::Text;

namespace DialogBoxObjects
{
    public ref class UserInformation
    {
    public:
        UserInformation()
        {
            firstNameValue = "";
            lastNameValue = "";
            emailAddressValue = "";
        }
    private:
        String^ firstNameValue;
    private:
        String^ lastNameValue;
    private:
        String^ emailAddressValue;
    public:
        property String^ FirstName
        {
            String^ get()
            {
                return firstNameValue;
            }
            void set( String^ value )
            {
                firstNameValue = value;
            }
        }
    public:
        property String^ LastName
        {
            String^ get()
            {
                return lastNameValue;
            }
            void set( String^ value )
            {
                lastNameValue = value;
            }
        }
    public:
        property String^ EmailAddress
        {
            String^ get()
            {
                return emailAddressValue;
            }
            void set( String^ value )
            {
                emailAddressValue = value;
            }
        }
    };
}

返回 InformationForm 的程式碼，然後加入 UserInformation 屬性。

Public ReadOnly Property UserInformation() As UserInformation
    Get
        Return _UI
    End Get
End Property

public UserInformation UserInformation
{
    get
    {
        return (_ui);
    }
}

public:
    property DialogBoxObjects::UserInformation^ UserInformation
    {
        DialogBoxObjects::UserInformation^ get()
        {
            return this->userInformation;
        }
    }

處理每一個 TextBox 控制項的 Validated 事件，這樣每當其中一個值變更時，就能夠更新 UserInformation 的對應屬性。

Private Sub FirstNameText_Validated(ByVal sender As Object, ByVal e As EventArgs) Handles FirstNameText.Validated
    Dim FirstNameTemp As String = FirstNameText.Text.Trim()
    If FirstNameText.Text.Trim().Length > 0 Then
        _UI.FirstName = FirstNameTemp
    End If
End Sub

Private Sub LastNameText_Validated(ByVal sender As Object, ByVal e As EventArgs) Handles LastNameText.Validated
    Dim LastNameTemp As String = LastNameText.Text.Trim()
    If LastNameText.Text.Trim().Length > 0 Then
        _UI.LastName = LastNameTemp
    End If
End Sub

Private Sub EmailText_Validated(ByVal sender As Object, ByVal e As EventArgs) Handles EmailText.Validated
    Dim EmailTemp As String = EmailText.Text.Trim()
    If EmailTemp.Length > 0 Then
        _UI.EmailAddress = EmailTemp
    End If
End Sub

public InformationForm()
{
    InitializeComponent();

    firstNameText.Validated += new EventHandler(firstNameText_Validated);
    lastNameText.Validated += new EventHandler(lastNameText_Validated);
    emailText.Validated += new EventHandler(emailText_Validated);
}

void firstNameText_Validated(object sender, EventArgs e)
{
    string firstNameTemp = firstNameText.Text.Trim();
    if (firstNameText.Text.Trim().Length > 0)
    {
        _ui.FirstName = firstNameTemp;
    }
}

void lastNameText_Validated(object sender, EventArgs e)
{
    string lastNameTemp = lastNameText.Text.Trim();
    if (lastNameText.Text.Trim().Length > 0)
    {
        _ui.LastName = lastNameTemp;
    }
}

void emailText_Validated(object sender, EventArgs e)
{
    string emailTemp = emailText.Text.Trim();
    if (emailTemp.Length > 0)
    {
        _ui.EmailAddress = emailTemp;
    }
}

    private:
        void FirstNameText_Validated(Object^ sender, EventArgs^ e)
        {
            String^ firstName = firstNameText->Text->Trim();
            if (firstName->Length > 0)
            {
                userInformation->FirstName = firstName;
            }
        }

    private:
        void LastNameText_Validated(Object^ sender, EventArgs^ e)
        {
            String^ lastName = lastNameText->Text->Trim();
            if (lastName->Length > 0)
            {
                userInformation->LastName = lastName;
            }
        }

    private:
        void EmailText_Validated(Object^ sender, EventArgs^ e)
        {
            String^ email = emailText->Text->Trim();
            if (email->Length > 0)
            {
                userInformation->EmailAddress = email;
            }
        }

    private:
        void CloseFormButton_Click(Object^ sender, EventArgs^ e)
        {
            if (userInformation->FirstName->Length == 0)
            {
                MessageBox::Show("First name cannot be zero-length.");
                return;
            }
            if (userInformation->LastName->Length == 0)
            {
                MessageBox::Show("Last name cannot be zero-length.");
                return;
            }
            if (userInformation->EmailAddress->Length == 0)
            {
                MessageBox::Show("Email address cannot be zero-length.");
                return;
            }

            this->DialogResult = ::DialogResult::OK;
            this->Hide();
        }




#pragma region Windows Form Designer generated code

        /// <summary>
        /// Required method for Designer support - do not modify
        /// the contents of this method with the code editor.
        /// </summary>
    private:
        void InitializeComponent()
        {
            this->tableLayoutPanel1 = 
                gcnew System::Windows::Forms::TableLayoutPanel();
            this->firstNameLabel = gcnew System::Windows::Forms::Label();
            this->lastNameLabel = gcnew System::Windows::Forms::Label();
            this->emailLabel = gcnew System::Windows::Forms::Label();
            this->firstNameText = gcnew System::Windows::Forms::TextBox();
            this->lastNameText = gcnew System::Windows::Forms::TextBox();
            this->emailText = gcnew System::Windows::Forms::TextBox();
            this->closeFormButton = gcnew System::Windows::Forms::Button();
            this->tableLayoutPanel1->SuspendLayout();
            this->SuspendLayout();
            //
            // tableLayoutPanel1
            //
            this->tableLayoutPanel1->ColumnCount = 2;
            this->tableLayoutPanel1->ColumnStyles->Add(
                gcnew System::Windows::Forms::ColumnStyle(
                System::Windows::Forms::SizeType::Percent, 33.98533F));
            this->tableLayoutPanel1->ColumnStyles->Add(
                gcnew System::Windows::Forms::ColumnStyle(
                System::Windows::Forms::SizeType::Percent, 66.01467F));
            this->tableLayoutPanel1->Controls->Add(this->firstNameLabel, 0, 0);
            this->tableLayoutPanel1->Controls->Add(this->lastNameLabel, 0, 1);
            this->tableLayoutPanel1->Controls->Add(this->emailLabel, 0, 2);
            this->tableLayoutPanel1->Controls->Add(this->firstNameText, 1, 0);
            this->tableLayoutPanel1->Controls->Add(this->lastNameText, 1, 1);
            this->tableLayoutPanel1->Controls->Add(this->emailText, 1, 2);
            this->tableLayoutPanel1->Location = System::Drawing::Point(33, 30);
            this->tableLayoutPanel1->Name = "tableLayoutPanel1";
            this->tableLayoutPanel1->RowCount = 3;
            this->tableLayoutPanel1->RowStyles->Add(
                gcnew System::Windows::Forms::RowStyle(
                System::Windows::Forms::SizeType::Percent, 50.0F));
            this->tableLayoutPanel1->RowStyles->Add(
                gcnew System::Windows::Forms::RowStyle(
                System::Windows::Forms::SizeType::Percent, 50.0F));
            this->tableLayoutPanel1->RowStyles->Add(
                gcnew System::Windows::Forms::RowStyle(
                System::Windows::Forms::SizeType::Absolute, 41.0F));
            this->tableLayoutPanel1->Size = System::Drawing::Size(658, 116);
            this->tableLayoutPanel1->TabIndex = 0;
            //
            // firstNameLabel
            //
            this->firstNameLabel->Anchor = 
                System::Windows::Forms::AnchorStyles::None;
            this->firstNameLabel->AutoSize = true;
            this->firstNameLabel->Location = System::Drawing::Point(82, 11);
            this->firstNameLabel->Name = "firstNameLabel";
            this->firstNameLabel->Size = System::Drawing::Size(59, 14);
            this->firstNameLabel->TabIndex = 0;
            this->firstNameLabel->Text = "First Name";
            //
            // lastNameLabel
            //
            this->lastNameLabel->Anchor = 
                System::Windows::Forms::AnchorStyles::None;
            this->lastNameLabel->AutoSize = true;
            this->lastNameLabel->Location = System::Drawing::Point(82, 48);
            this->lastNameLabel->Name = "lastNameLabel";
            this->lastNameLabel->Size = System::Drawing::Size(59, 14);
            this->lastNameLabel->TabIndex = 1;
            this->lastNameLabel->Text = "Last Name";
            //
            // emailLabel
            //
            this->emailLabel->Anchor = 
                System::Windows::Forms::AnchorStyles::None;
            this->emailLabel->AutoSize = true;
            this->emailLabel->Location = System::Drawing::Point(73, 88);
            this->emailLabel->Name = "emailLabel";
            this->emailLabel->Size = System::Drawing::Size(77, 14);
            this->emailLabel->TabIndex = 2;
            this->emailLabel->Text = "Email Address";
            //
            // firstNameText
            //
            this->firstNameText->Anchor = 
                System::Windows::Forms::AnchorStyles::None;
            this->firstNameText->Location = System::Drawing::Point(339, 8);
            this->firstNameText->Name = "firstNameText";
            this->firstNameText->Size = System::Drawing::Size(203, 20);
            this->firstNameText->TabIndex = 3;
            //
            // lastNameText
            //
            this->lastNameText->Anchor = 
                System::Windows::Forms::AnchorStyles::None;
            this->lastNameText->Location = System::Drawing::Point(339, 45);
            this->lastNameText->Name = "lastNameText";
            this->lastNameText->Size = System::Drawing::Size(202, 20);
            this->lastNameText->TabIndex = 4;
            //
            // emailText
            //
            this->emailText->Anchor = 
                System::Windows::Forms::AnchorStyles::None;
            this->emailText->Location = System::Drawing::Point(336, 85);
            this->emailText->Name = "emailText";
            this->emailText->Size = System::Drawing::Size(208, 20);
            this->emailText->TabIndex = 5;
            //
            // closeFormButton
            //
            this->closeFormButton->Location = System::Drawing::Point(550, 211);
            this->closeFormButton->Name = "closeFormButton";
            this->closeFormButton->Size = System::Drawing::Size(141, 23);
            this->closeFormButton->TabIndex = 1;
            this->closeFormButton->Text = "OK";
            this->closeFormButton->Click += gcnew System::EventHandler(this,
                &InformationForm::CloseFormButton_Click);
            //
            // InformationForm
            //
            this->AutoScaleDimensions = System::Drawing::SizeF(6.0F, 13.0F);
            this->AutoScaleMode = System::Windows::Forms::AutoScaleMode::Font;
            this->ClientSize = System::Drawing::Size(744, 258);
            this->Controls->Add(this->closeFormButton);
            this->Controls->Add(this->tableLayoutPanel1);
            this->Name = "InformationForm";
            this->Text = "User Information";
            this->tableLayoutPanel1->ResumeLayout(false);
            this->tableLayoutPanel1->PerformLayout();
            this->ResumeLayout(false);

        }

#pragma endregion

    public:
        InformationForm()
        {
            userInformation = gcnew DialogBoxObjects::UserInformation;

            components = nullptr;
            InitializeComponent();

            firstNameText->Validated += gcnew EventHandler
                (this, &InformationForm::FirstNameText_Validated);
            lastNameText->Validated += gcnew EventHandler(this, 
                &InformationForm::LastNameText_Validated);
            emailText->Validated += gcnew EventHandler(this, 
                &InformationForm::EmailText_Validated);
        }

將 Validated 事件的處理常式加入至表單上的每一個 TextBox 控制項，這樣每當使用者變更控制項的值時，這些控制項的新值就會指派給 UserInformation。

Private Sub closeFormButton_Click(ByVal sender As Object, ByVal e As EventArgs)
    If _UI.FirstName.Length = 0 Then
        MessageBox.Show("First name cannot be zero-length.")
        Exit Sub
    End If
    If _UI.LastName.Length = 0 Then
        MessageBox.Show("Last name cannot be zero-length.")
        Exit Sub
    End If
    If _UI.EmailAddress.Length = 0 Then
        MessageBox.Show("Email address cannot be zero-length.")
        Exit Sub
    End If

    Me.DialogResult = System.Windows.Forms.DialogResult.OK
    Me.Close()
End Sub

private void closeFormButton_Click(object sender, EventArgs e)
{
    if (_ui.FirstName.Length == 0)
    {
        MessageBox.Show("First name cannot be zero-length.");
        return;
    }
    if (_ui.LastName.Length == 0)
    {
        MessageBox.Show("Last name cannot be zero-length.");
        return;
    }
    if (_ui.EmailAddress.Length == 0)
    {
        MessageBox.Show("Email address cannot be zero-length.");
        return;
    }

    this.DialogResult = DialogResult.OK;
    this.Hide();
}

private:
    void CloseFormButton_Click(Object^ sender, EventArgs^ e)
    {
        if (userInformation->FirstName->Length == 0)
        {
            MessageBox::Show("First name cannot be zero-length.");
            return;
        }
        if (userInformation->LastName->Length == 0)
        {
            MessageBox::Show("Last name cannot be zero-length.");
            return;
        }
        if (userInformation->EmailAddress->Length == 0)
        {
            MessageBox::Show("Email address cannot be zero-length.");
            return;
        }

        this->DialogResult = ::DialogResult::OK;
        this->Hide();
    }

若要顯示已建立的對話方塊並使用物件擷取資料

在 Visual Studio 中選取 [Form1]。將 Button 加入至表單，然後將它的 Name 屬性變更為 showFormButton。
按兩下此按鈕，以加入會呼叫對話方塊並顯示結果的事件處理常式。

Private Sub ShowFormButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ShowFormButton.Click
    Dim InfoForm As New InformationForm()
    Dim dr As DialogResult = InfoForm.ShowDialog()
    If dr = System.Windows.Forms.DialogResult.OK Then
        Dim Txt As String = "First Name: " & InfoForm.UserInformation.FirstName + ControlChars.Cr + ControlChars.Lf
        Txt &= "Last Name: " & InfoForm.UserInformation.LastName + ControlChars.Cr + ControlChars.Lf
        Txt &= "Email Address: " & InfoForm.UserInformation.EmailAddress

        MessageBox.Show(Txt)
    End If

    InfoForm.Dispose()
End Sub

請參閱

共用方式為

逐步解說：使用物件共同地擷取對話方塊資訊

若要建立透過物件公開其資訊的對話方塊

若要顯示已建立的對話方塊並使用物件擷取資料

請參閱

工作

概念

其他資源

其他資源