HelpProvider.GetHelpString メソッド

.NET Framework クラス ライブラリ リファレンス

HelpProvider.GetHelpString メソッド

指定したコントロールのポップアップ ヘルプ ウィンドウの内容を返します。

名前空間: System.Windows.Forms
アセンブリ: System.Windows.Forms (system.windows.forms.dll 内)
構文

Visual Basic (宣言)

<LocalizableAttribute(True)> _
Public Overridable Function
 GetHelpString ( _
    ctl As Control _
) As String

Visual Basic (使用法)

Dim instance As HelpProvider
Dim ctl As Control
Dim returnValue As String

returnValue = instance.GetHelpString(ctl)

C#

[LocalizableAttribute(true)] 
public virtual string GetHelpString (
    Control ctl
)

C++

[LocalizableAttribute(true)] 
public:
virtual String^ GetHelpString (
    Control^ ctl
)

J#

/** @attribute LocalizableAttribute(true) */ 
public String GetHelpString (
    Control ctl
)

JScript

LocalizableAttribute(true) 
public function GetHelpString (
    ctl : Control
) : String

パラメータ

ctl

ヘルプ文字列の取得対象となる Control。

戻り値
このコントロールに関連付けられたヘルプ文字列。既定値は null 参照 (Visual Basic では Nothing) です。

解説

実行時にこのヘルプ文字列を表示するには、指定したコントロールに入力フォーカスがあるときに、ユーザーは F1 キーを押します。

使用例

KeyPressEventHandler クラスと KeyEventHandler クラスを使用して入力をフィルタする方法を示すコード例を次に示します。この例はまた、GetHelpString メソッドの処理方法も示しています。この例は完結したコードです。これをプロジェクトに追加して、実行できます。

Visual Basic

Imports System.Drawing
Imports System.Windows.Forms
Imports System
Imports Microsoft.VisualBasic

Public Class Form1
    Inherits System.Windows.Forms.Form

    Public Sub New()
        MyBase.New()

        InitializeComponent()
        AddHandlers()
        InitializeFormHelp()

    End Sub

    
    Friend WithEvents Label1 As
 System.Windows.Forms.Label
    Friend WithEvents Label2 As
 System.Windows.Forms.Label
    Friend WithEvents Label3 As
 System.Windows.Forms.Label
    Friend WithEvents withdrawal As
 System.Windows.Forms.TextBox
    Friend WithEvents deposit As
 System.Windows.Forms.TextBox
    Friend WithEvents ErrorProvider1 As
 System.Windows.Forms.ErrorProvider
    Friend WithEvents balance As
 System.Windows.Forms.Label
    Friend WithEvents HelpProvider1 As
 System.Windows.Forms.HelpProvider

   <System.Diagnostics.DebuggerStepThrough()> Private Sub
     InitializeComponent()
        Me.withdrawal = New System.Windows.Forms.TextBox
        Me.deposit = New System.Windows.Forms.TextBox
        Me.Label1 = New System.Windows.Forms.Label
        Me.Label2 = New System.Windows.Forms.Label
        Me.Label3 = New System.Windows.Forms.Label
        Me.ErrorProvider1 = New System.Windows.Forms.ErrorProvider
        Me.balance = New System.Windows.Forms.Label
        Me.HelpProvider1 = New System.Windows.Forms.HelpProvider
        Me.SuspendLayout()
        
        Me.withdrawal.Location = New System.Drawing.Point(32,
 200)
        Me.withdrawal.Name = "withdrawal"
        Me.withdrawal.Size = New System.Drawing.Size(88,
 20)
        Me.withdrawal.TabIndex = 0
        Me.withdrawal.Text = ""
       
        Me.deposit.Location = New System.Drawing.Point(168,
 200)
        Me.deposit.Name = "deposit"
        Me.deposit.TabIndex = 1
        Me.deposit.Text = ""
       
        Me.Label1.Location = New System.Drawing.Point(56,
 88)
        Me.Label1.Name = "Label1"
        Me.Label1.Size = New System.Drawing.Size(96,
 24)
        Me.Label1.TabIndex = 2
        Me.Label1.Text = "Account Balance:"
       
        Me.Label2.Location = New System.Drawing.Point(168,
 168)
        Me.Label2.Name = "Label2"
        Me.Label2.Size = New System.Drawing.Size(96,
 24)
        Me.Label2.TabIndex = 4
        Me.Label2.Text = "Deposit:"
        
        Me.Label3.Location = New System.Drawing.Point(32,
 168)
        Me.Label3.Name = "Label3"
        Me.Label3.Size = New System.Drawing.Size(96,
 24)
        Me.Label3.TabIndex = 5
        Me.Label3.Text = "Withdrawal:"
        
        Me.ErrorProvider1.ContainerControl = Me
        
        Me.balance.BorderStyle = System.Windows.Forms.BorderStyle.Fixed3D
        Me.balance.Location = New System.Drawing.Point(152,
 88)
        Me.balance.Name = "balance"
        Me.balance.TabIndex = 6
        Me.balance.Text = "345.65"
        Me.balance.TextAlign = System.Drawing.ContentAlignment.MiddleLeft
        
        Me.ClientSize = New System.Drawing.Size(292,
 266)
        Me.Controls.Add(Me.balance)
        Me.Controls.Add(Me.Label3)
        Me.Controls.Add(Me.Label2)
        Me.Controls.Add(Me.Label1)
        Me.Controls.Add(Me.deposit)
        Me.Controls.Add(Me.withdrawal)
        Me.Name = "Form1"
        Me.Text = "Form1"
        Me.ResumeLayout(False)

    End Sub
 
   
    
    Private Sub AddHandlers()

        'Add the event-handler delegates to handle the KeyDown events.
        AddHandler deposit.KeyDown, _
            New KeyEventHandler(AddressOf ProcessEntry)
        AddHandler withdrawal.KeyDown, _
            New KeyEventHandler(AddressOf ProcessEntry)

        'Add the event-handler delegates to handled the KeyPress events.
        AddHandler deposit.KeyPress, _
            New KeyPressEventHandler(AddressOf
 CheckForDigits)
        AddHandler withdrawal.KeyPress, _
            New KeyPressEventHandler(AddressOf
 CheckForDigits)

    End Sub
    Private Sub InitializeFormHelp()

        ' Set the form's border to the FixedDialog style.
        Me.FormBorderStyle = FormBorderStyle.FixedDialog

        ' Remove the Maximize and Minimize buttons from the form.
        Me.MaximizeBox = False
        Me.MinimizeBox = False

        ' Add the Help button to the form.
        Me.HelpButton = True

        ' Set the Help string for the deposit textBox.
        HelpProvider1.SetHelpString(deposit, _
            "Enter an amount in the format xxx.xx"
 _
                & "and press Enter to deposit.")

        ' Set the Help string for the withdrawal textBox.
        HelpProvider1.SetHelpString(withdrawal, _
            "Enter an amount in the format xxx.xx"
 _
            & "and press Enter to withdraw.")

    End Sub

    Private Sub ProcessEntry(ByVal
 sender As Object, _
        ByVal e As KeyEventArgs)

        ' Cast the sender back to a TextBox.
        Dim textBoxSender As Control = CType(sender,
 TextBox)

        ' Set the error description to an empty string ().
        ErrorProvider1.SetError(textBoxSender, "")

        ' Declare the variable to hold the new balance.
        Dim newBalance As Double

        ' Wrap the code in a Try/Catch block to catch 
        ' errors that can occur when converting the string 
        ' to a double.

        Try
            If (e.KeyCode = Keys.Enter) Then

                ' Switch on the text box that received
                ' the KeyPress event. Convert the text to type double
,
                ' and compute the new balance.
                Select Case textBoxSender.Name
                    Case "withdrawal"
                        newBalance = Double.Parse(balance.Text)
 _
                            - Double.Parse(withdrawal.Text)
                        withdrawal.Text = ""
                    Case "deposit"
                        newBalance = Double.Parse(balance.Text)
 _
                            + Double.Parse(deposit.Text)
                        deposit.Text = ""
                End Select

                ' Check the value of new balance and set the
                ' Forecolor property accordingly.
                If (newBalance < 0) Then
                    balance.ForeColor = Color.Red
                Else
                    balance.ForeColor = Color.Black
                End If

                ' Set the text of the balance text box
                ' to the newBalance value.
                balance.Text = newBalance.ToString
            End If

        Catch ex As FormatException

            ' If a FormatException is thrown, set the
            ' error string to the HelpString message for 
            ' the control.
            ErrorProvider1.SetError(textBoxSender, _
                HelpProvider1.GetHelpString(textBoxSender))
        End Try
    End Sub


    Private Sub CheckForDigits(ByVal
 sender As Object, ByVal
 e _
        As KeyPressEventArgs)

        ' If the character is not a digit, period, or backspace then
        ' ignore it by setting the KeyPressEventArgs.Handled
        ' property to true.
        If Not (Char.IsDigit(e.KeyChar)
 _
            Or e.KeyChar = "."
 Or e.KeyChar = ChrW(Keys.Back)) Then
            e.Handled = True
        End If
    End Sub
   

    Public Shared Sub Main()
        Application.Run(New Form1)
    End Sub

End Class

C#

   
using System.Drawing;
using System.Windows.Forms;
using System;
using Microsoft.VisualBasic;

public class Form1:
    System.Windows.Forms.Form

{

    public Form1() : base()
    {        

        InitializeComponent();
        AddHandlers();
        InitializeFormHelp();

    }

    internal System.Windows.Forms.Label Label1;
    internal System.Windows.Forms.Label Label2;
    internal System.Windows.Forms.Label Label3;
    internal System.Windows.Forms.TextBox withdrawal;
    internal System.Windows.Forms.TextBox deposit;
    internal System.Windows.Forms.ErrorProvider ErrorProvider1;
    internal System.Windows.Forms.Label balance;
    internal System.Windows.Forms.HelpProvider HelpProvider1;
    
[System.Diagnostics.DebuggerStepThrough]
    private void InitializeComponent()
    {
        this.withdrawal = new System.Windows.Forms.TextBox();
        this.deposit = new System.Windows.Forms.TextBox();
        this.Label1 = new System.Windows.Forms.Label();
        this.Label2 = new System.Windows.Forms.Label();
        this.Label3 = new System.Windows.Forms.Label();
        this.ErrorProvider1 = new         System.Windows.Forms.ErrorProvider();
        this.balance = new System.Windows.Forms.Label();
        this.HelpProvider1 = new         System.Windows.Forms.HelpProvider();
        this.SuspendLayout();
        
        this.withdrawal.Location = new System.Drawing.Point(32,
 200);
        this.withdrawal.Name = "withdrawal";
        this.withdrawal.Size = new System.Drawing.Size(88,
 20);
        this.withdrawal.TabIndex = 0;
        this.withdrawal.Text = "";
        
        this.deposit.Location = new System.Drawing.Point(168,
 200);
        this.deposit.Name = "deposit";
        this.deposit.TabIndex = 1;
        this.deposit.Text = "";
        
        this.Label1.Location = new System.Drawing.Point(56,
 88);
        this.Label1.Name = "Label1";
        this.Label1.Size = new System.Drawing.Size(96,
 24);
        this.Label1.TabIndex = 2;
        this.Label1.Text = "Account Balance:";
        
        this.Label2.Location = new System.Drawing.Point(168,
 168);
        this.Label2.Name = "Label2";
        this.Label2.Size = new System.Drawing.Size(96,
 24);
        this.Label2.TabIndex = 4;
        this.Label2.Text = "Deposit:";
        
        this.Label3.Location = new System.Drawing.Point(32,
 168);
        this.Label3.Name = "Label3";
        this.Label3.Size = new System.Drawing.Size(96,
 24);
        this.Label3.TabIndex = 5;
        this.Label3.Text = "Withdrawal:";
        
        this.ErrorProvider1.ContainerControl = this;
        
        this.balance.BorderStyle = System.Windows.Forms.BorderStyle.Fixed3D;
        this.balance.Location = new System.Drawing.Point(152,
 88);
        this.balance.Name = "balance";
        this.balance.TabIndex = 6;
        this.balance.Text = "345.65";
        this.balance.TextAlign = System.Drawing.ContentAlignment.MiddleLeft;
        
        this.ClientSize = new System.Drawing.Size(292,
 266);
        this.Controls.Add(this.balance);
        this.Controls.Add(this.Label3);
        this.Controls.Add(this.Label2);
        this.Controls.Add(this.Label1);
        this.Controls.Add(this.deposit);
        this.Controls.Add(this.withdrawal);
        this.Name = "Form1";
        this.Text = "Form1";
        this.ResumeLayout(false);

    }

    private void AddHandlers()
    {
        // Add the event-handler delegates to handled the KeyDown
        // events.
        deposit.KeyDown +=new KeyEventHandler(ProcessEntry); 
 
        withdrawal.KeyDown += new KeyEventHandler(ProcessEntry);

        // Add the event-handler delegates to handled the KeyPress 
        // events.
        deposit.KeyPress += new KeyPressEventHandler(CheckForDigits);
        withdrawal.KeyPress += 
            new KeyPressEventHandler(CheckForDigits);
    }

    private void InitializeFormHelp()
    {

        // Set the form's border to the FixedDialog style.
        this.FormBorderStyle = FormBorderStyle.FixedDialog;

        // Remove the Maximize and Minimize buttons from the form.
        this.MaximizeBox = false;
        this.MinimizeBox = false;

        // Add the Help button to the form.
        this.HelpButton = true;

        // Set the Help string for the deposit textBox.
        HelpProvider1.SetHelpString(deposit, 
            "Enter an amount in the format xxx.xx" +
            "and press Enter to deposit.");

        // Set the Help string for the withdrawal textBox.
        HelpProvider1.SetHelpString(withdrawal, 
            "Enter an amount in the format xxx.xx" +
            "and press Enter to withdraw.");

    }

    private void ProcessEntry(object sender,
 KeyEventArgs e)
    {

        // Cast the sender back to a TextBox.
        Control textBoxSender = (TextBox) sender;

        // Set the error description to an empty string ().
        ErrorProvider1.SetError(textBoxSender, "");

        // Declare the variable to hold the new balance.
        double newBalance = 0;

        // Wrap the code in a Try/Catch block to catch 
        // errors that can occur when converting the string 
        // to a double.

        try
        {
            if (e.KeyCode==Keys.Enter)

                // Switch on the text box that received
                // the KeyPress event. Convert the text to type double
,
                // and compute the new balance.
            {
                switch(textBoxSender.Name)
                {
                    case "withdrawal":
                        newBalance = Double.Parse(balance.Text) 
                            - Double.Parse(withdrawal.Text);
                        withdrawal.Text = "";
                        break;
                    case "deposit":
                        newBalance = Double.Parse(balance.Text) 
                            + Double.Parse(deposit.Text);
                        deposit.Text = "";
                        break;
                }

                // Check the value of new balance and set the
                // Forecolor property accordingly.
                if (newBalance < 0)
                {
                    balance.ForeColor = Color.Red;
                }
                else
                {
                    balance.ForeColor = Color.Black;
                }

                // Set the text of the balance text box
                // to the newBalance value.
                balance.Text = newBalance.ToString();
            }

        }
        catch(FormatException)
        {

            // If a FormatException is thrown, set the
            // error string to the HelpString message for 
            // the control.
            ErrorProvider1.SetError(textBoxSender, 
                HelpProvider1.GetHelpString(textBoxSender));
        }
    }


    private void CheckForDigits(object sender,
 KeyPressEventArgs e)
    {

        // If the character is not a digit, period, or backspace then
        // ignore it by setting the KeyPressEventArgs.Handled
        // property to true.
        if (!(Char.IsDigit(e.KeyChar) || e.KeyChar == '.' || 
            e.KeyChar == (char)(Keys.Back)))
        {
            e.Handled = true;
        }
    }
    

    public static void Main()
    {
        Application.Run(new Form1());
    }


}

C++

#using <System.dll>
#using <Microsoft.VisualBasic.dll>
#using <System.Windows.Forms.dll>
#using <System.Drawing.dll>

using namespace System::Drawing;
using namespace System::Windows::Forms;
using namespace System;
using namespace Microsoft::VisualBasic;
public ref class Form1: public
 System::Windows::Forms::Form
{
public:
   Form1()
      : Form()
   {
      InitializeComponent();
      AddHandlers();
      InitializeFormHelp();
   }


public private:
   System::Windows::Forms::Label ^ Label1;
   System::Windows::Forms::Label ^ Label2;
   System::Windows::Forms::Label ^ Label3;
   System::Windows::Forms::TextBox^ withdrawal;
   System::Windows::Forms::TextBox^ deposit;
   System::Windows::Forms::ErrorProvider^ ErrorProvider1;
   System::Windows::Forms::Label ^ balance;
   System::Windows::Forms::HelpProvider^ HelpProvider1;

private:

   [System::Diagnostics::DebuggerStepThrough]
   void InitializeComponent()
   {
      this->withdrawal = gcnew System::Windows::Forms::TextBox;
      this->deposit = gcnew System::Windows::Forms::TextBox;
      this->Label1 = gcnew System::Windows::Forms::Label;
      this->Label2 = gcnew System::Windows::Forms::Label;
      this->Label3 = gcnew System::Windows::Forms::Label;
      this->ErrorProvider1 = gcnew System::Windows::Forms::ErrorProvider;
      this->balance = gcnew System::Windows::Forms::Label;
      this->HelpProvider1 = gcnew System::Windows::Forms::HelpProvider;
      this->SuspendLayout();
      this->withdrawal->Location = System::Drawing::Point(
 32, 200 );
      this->withdrawal->Name = "withdrawal";
      this->withdrawal->Size = System::Drawing::Size( 88,
 20 );
      this->withdrawal->TabIndex = 0;
      this->withdrawal->Text = "";
      this->deposit->Location = System::Drawing::Point(
 168, 200 );
      this->deposit->Name = "deposit";
      this->deposit->TabIndex = 1;
      this->deposit->Text = "";
      this->Label1->Location = System::Drawing::Point( 56,
 88 );
      this->Label1->Name = "Label1";
      this->Label1->Size = System::Drawing::Size( 96, 24
 );
      this->Label1->TabIndex = 2;
      this->Label1->Text = "Account Balance:";
      this->Label2->Location = System::Drawing::Point( 168,
 168 );
      this->Label2->Name = "Label2";
      this->Label2->Size = System::Drawing::Size( 96, 24
 );
      this->Label2->TabIndex = 4;
      this->Label2->Text = "Deposit:";
      this->Label3->Location = System::Drawing::Point( 32,
 168 );
      this->Label3->Name = "Label3";
      this->Label3->Size = System::Drawing::Size( 96, 24
 );
      this->Label3->TabIndex = 5;
      this->Label3->Text = "Withdrawal:";
      this->ErrorProvider1->ContainerControl = this;
      this->balance->BorderStyle = System::Windows::Forms::BorderStyle::Fixed3D;
      this->balance->Location = System::Drawing::Point(
 152, 88 );
      this->balance->Name = "balance";
      this->balance->TabIndex = 6;
      this->balance->Text = "345.65";
      this->balance->TextAlign = System::Drawing::ContentAlignment::MiddleLeft;
      this->ClientSize = System::Drawing::Size( 292, 266 );
      this->Controls->Add( this->balance
 );
      this->Controls->Add( this->Label3
 );
      this->Controls->Add( this->Label2
 );
      this->Controls->Add( this->Label1
 );
      this->Controls->Add( this->deposit
 );
      this->Controls->Add( this->withdrawal
 );
      this->Name = "Form1";
      this->Text = "Form1";
      this->ResumeLayout( false );
   }

   void AddHandlers()
   {
      
      // Add the event-handler delegates to handled the KeyDown
      // events.
      deposit->KeyDown += gcnew KeyEventHandler( this, &Form1::ProcessEntry
 );
      withdrawal->KeyDown += gcnew KeyEventHandler( this, &Form1::ProcessEntry
 );
      
      // Add the event-handler delegates to handled the KeyPress 
      // events.
      deposit->KeyPress += gcnew KeyPressEventHandler( this,
 &Form1::CheckForDigits );
      withdrawal->KeyPress += gcnew KeyPressEventHandler( this,
 &Form1::CheckForDigits );
   }


   void InitializeFormHelp()
   {
      
      // Set the form's border to the FixedDialog style.
      this->FormBorderStyle = ::FormBorderStyle::FixedDialog;
      
      // Remove the Maximize and Minimize buttons from the form.
      this->MaximizeBox = false;
      this->MinimizeBox = false;
      
      // Add the Help button to the form.
      this->HelpButton = true;
      
      // Set the Help string for the deposit textBox.
      HelpProvider1->SetHelpString( deposit, "Enter an amount in
 the format xxx.xx"
      "and press Enter to deposit." );
      
      // Set the Help string for the withdrawal textBox.
      HelpProvider1->SetHelpString( withdrawal, "Enter an amount in
 the format xxx.xx"
      "and press Enter to withdraw." );
   }




   void ProcessEntry( Object^ sender, KeyEventArgs^ e )
   {
      
      // Cast the sender back to a TextBox.
      Control^ textBoxSender = dynamic_cast<TextBox^>(sender);
      
      // Set the error description to an empty string ().
      ErrorProvider1->SetError( textBoxSender, "" );
      
      // Declare the variable to hold the new balance.
      double newBalance = 0;
      
      // Wrap the code in a Try/Catch block to catch 
      // errors that can occur when converting the string 
      // to a double.
      try
      {
         if ( e->KeyCode == Keys::Enter )
         {
            if ( textBoxSender->Name->Equals( "withdrawal"
 ) )
            {
               newBalance = Double::Parse( balance->Text ) - Double::Parse( withdrawal->Text
 );
               withdrawal->Text = "";
            }
            else
            if ( textBoxSender->Name->Equals( "deposit"
 ) )
            {
               newBalance = Double::Parse( balance->Text ) + Double::Parse( deposit->Text
 );
               deposit->Text = "";
            }
            
            // Check the value of new balance and set the
            // Forecolor property accordingly.
            if ( newBalance < 0 )
            {
               balance->ForeColor = Color::Red;
            }
            else
            {
               balance->ForeColor = Color::Black;
            }
            
            // Set the text of the balance text box
            // to the newBalance value.
            balance->Text = newBalance.ToString();
         }
      }
      catch ( FormatException^ ) 
      {
         
         // If a FormatException is thrown, set the
         // error string to the HelpString message for 
         // the control.
         ErrorProvider1->SetError( textBoxSender, HelpProvider1->GetHelpString(
 textBoxSender ) );
      }

   }

   void CheckForDigits( Object^ /*sender*/, KeyPressEventArgs^
 e )
   {
      
      // If the character is not a digit, period, or backspace then
      // ignore it by setting the KeyPressEventArgs.Handled
      // property to true.
      if (  !(Char::IsDigit( e->KeyChar ) || e->KeyChar
 == '.' || e->KeyChar == (char)(Keys::Back)) )
      {
         e->Handled = true;
      }
   }

};

int main()
{
   Application::Run( gcnew Form1 );
}

J#

import System.Drawing.*;
import System.Windows.Forms.*;
import System.*;
import Microsoft.VisualBasic.*;

public class Form1 extends System.Windows.Forms.Form
{
    public Form1()
    {
        InitializeComponent();
        AddHandlers();
        InitializeFormHelp();
    } //Form1 

    private System.Windows.Forms.Label label1;
    private System.Windows.Forms.Label label2;
    private System.Windows.Forms.Label label3;
    private System.Windows.Forms.TextBox withdrawal;
    private System.Windows.Forms.TextBox deposit;
    private System.Windows.Forms.ErrorProvider errorProvider1;
    private System.Windows.Forms.Label balance;
    private System.Windows.Forms.HelpProvider helpProvider1;

    /** @attribute System.Diagnostics.DebuggerStepThrough()
     */
    private void InitializeComponent()
    {
        this.withdrawal = new System.Windows.Forms.TextBox();
        this.deposit = new System.Windows.Forms.TextBox();
        this.label1 = new System.Windows.Forms.Label();
        this.label2 = new System.Windows.Forms.Label();
        this.label3 = new System.Windows.Forms.Label();
        this.errorProvider1 = new System.Windows.Forms.ErrorProvider();
        this.balance = new System.Windows.Forms.Label();
        this.helpProvider1 = new System.Windows.Forms.HelpProvider();
        this.SuspendLayout();

        this.withdrawal.set_Location(new System.Drawing.Point(32,
 200));
        this.withdrawal.set_Name("withdrawal");
        this.withdrawal.set_Size(new System.Drawing.Size(88,
 20));
        this.withdrawal.set_TabIndex(0);
        this.withdrawal.set_Text("");

        this.deposit.set_Location(new System.Drawing.Point(168,
 200));
        this.deposit.set_Name("deposit");
        this.deposit.set_TabIndex(1);
        this.deposit.set_Text("");

        this.label1.set_Location(new System.Drawing.Point(56,
 88));
        this.label1.set_Name("Label1");
        this.label1.set_Size(new System.Drawing.Size(96,
 24));
        this.label1.set_TabIndex(2);
        this.label1.set_Text("Account Balance:");

        this.label2.set_Location(new System.Drawing.Point(168,
 168));
        this.label2.set_Name("Label2");
        this.label2.set_Size(new System.Drawing.Size(96,
 24));
        this.label2.set_TabIndex(4);
        this.label2.set_Text("Deposit:");

        this.label3.set_Location(new System.Drawing.Point(32,
 168));
        this.label3.set_Name("Label3");
        this.label3.set_Size(new System.Drawing.Size(96,
 24));
        this.label3.set_TabIndex(5);
        this.label3.set_Text("Withdrawal:");

        this.errorProvider1.set_ContainerControl(this);

        this.balance.set_BorderStyle(System.Windows.Forms.BorderStyle.Fixed3D);
        this.balance.set_Location(new System.Drawing.Point(152,
 88));
        this.balance.set_Name("balance");
        this.balance.set_TabIndex(6);
        this.balance.set_Text("345.65");
        this.balance.set_TextAlign(System.Drawing.ContentAlignment.MiddleLeft);

        this.set_ClientSize(new System.Drawing.Size(292,
 266));
        this.get_Controls().Add(this.balance);
        this.get_Controls().Add(this.label3);
        this.get_Controls().Add(this.label2);
        this.get_Controls().Add(this.label1);
        this.get_Controls().Add(this.deposit);
        this.get_Controls().Add(this.withdrawal);
        this.set_Name("Form1");
        this.set_Text("Form1");
        this.ResumeLayout(false);
    } //InitializeComponent

    private void AddHandlers()
    {
        // Add the event-handler delegates to handled the KeyDown
        // events.
        deposit.add_KeyDown(new KeyEventHandler(ProcessEntry));
        withdrawal.add_KeyDown(new KeyEventHandler(ProcessEntry));
        // Add the event-handler delegates to handled the KeyPress 
        // events.
        deposit.add_KeyPress(new KeyPressEventHandler(CheckForDigits));
        withdrawal.add_KeyPress(new KeyPressEventHandler(CheckForDigits));
    } //AddHandlers

    private void InitializeFormHelp()
    {
        // Set the form's border to the FixedDialog style.
        this.set_FormBorderStyle(get_FormBorderStyle().FixedDialog);
        // Remove the Maximize and Minimize buttons from the form.
        this.set_MaximizeBox(false);
        this.set_MinimizeBox(false);
        // Add the Help button to the form.
        this.set_HelpButton(true);
        // Set the Help string for the deposit textBox.
        helpProvider1.SetHelpString(deposit, 
            "Enter an amount in the format xxx.xx" 
            + "and press Enter to deposit.");
        // Set the Help string for the withdrawal textBox.
        helpProvider1.SetHelpString(withdrawal, 
            "Enter an amount in the format xxx.xx" 
            + "and press Enter to withdraw.");
    } //InitializeFormHelp

    private void ProcessEntry(Object sender,
 KeyEventArgs e)
    {
        // Cast the sender back to a TextBox.
        Control textBoxSender = (TextBox)sender;
        // Set the error description to an empty string ().
        errorProvider1.SetError(textBoxSender, "");
        // Declare the variable to hold the new balance.
        double newBalance = 0;
        // Wrap the code in a Try/Catch block to catch 
        // errors that can occur when converting the string 
        // to a double.
        try {
            if (e.get_KeyCode().Equals(Keys.Enter)) {
                // Switch on the text box that received
                // the KeyPress event. Convert the text to type double
,
                // and compute the new balance.
                if (textBoxSender.get_Name().Equals("withdrawal"))
 {
                    newBalance = System.Double.Parse(balance.get_Text()) 
                        - System.Double.Parse(withdrawal.get_Text());
                    withdrawal.set_Text("");
                }
                if (textBoxSender.get_Name().Equals("deposit"))
 {
                    newBalance = System.Double.Parse(balance.get_Text()) 
                        + System.Double.Parse(deposit.get_Text());
                    deposit.set_Text("");
                }
                // Check the value of new balance and set the
                // Forecolor property accordingly.
                if (newBalance < 0) {
                    balance.set_ForeColor(Color.get_Red());
                }
                else {
                    balance.set_ForeColor(Color.get_Black());
                }
                // Set the text of the balance text box
                // to the newBalance value.
                balance.set_Text(System.Convert.ToString(newBalance));
            }
        }
        catch (FormatException exp) {
            // If a FormatException is thrown, set the
            // error string to the HelpString message for 
            // the control.
            errorProvider1.SetError(textBoxSender, 
                helpProvider1.GetHelpString(textBoxSender));
        }
    } //ProcessEntry

    private void CheckForDigits(Object sender,
 KeyPressEventArgs e)
    {
        // If the character is not a digit, period, or backspace then
        // ignore it by setting the KeyPressEventArgs.Handled
        // property to true.
        if (!((Char.IsDigit(e.get_KeyChar()) || e.get_KeyChar()
 == '.' 
            || e.get_KeyChar() == (char)Keys.Back))) {
            e.set_Handled(true);
        }
    } //CheckForDigits

    public static void main(String[]
 args)
    {
        Application.Run(new Form1());
    } //main
} //Form1 

プラットフォーム

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

開発プラットフォームの中には、.NET Framework によってサポートされていないバージョンがあります。サポートされているバージョンについては、「システム要件」を参照してください。

バージョン情報

.NET Framework
サポート対象 : 2.0、1.1、1.0

参照

関連項目
HelpProvider クラス
HelpProvider メンバ
System.Windows.Forms 名前空間
GetHelpString
GetHelpKeyword
GetShowHelp
SetHelpString
SetHelpKeyword