MessageBox 类

定义

显示消息窗口(也称为对话框),向用户显示消息。Displays a message window, also known as a dialog box, which presents a message to the user. 这是一个模式窗口,可阻止应用程序中的其他操作,直到用户将其关闭。It is a modal window, blocking other actions in the application until the user closes it. MessageBox 可包含通知并指示用户的文本、按钮和符号。A MessageBox can contain text, buttons, and symbols that inform and instruct the user.

public ref class MessageBox
public class MessageBox
type MessageBox = class
Public Class MessageBox
继承
MessageBox

示例

下面的代码示例演示如何使用MessageBox来向用户通知TextBox中缺少的条目。The following code example shows how to use a MessageBox to inform the user of a missing entry in a TextBox. 此示例要求从具有TextBox命名ServerName的现有窗体调用方法。This example requires that the method is called from an existing form with a TextBox named ServerName on it.

private:
   void validateUserEntry()
   {
      // Checks the value of the text.
      if ( serverName->Text->Length == 0 )
      {
         // Initializes the variables to pass to the MessageBox::Show method.
         String^ message = "You did not enter a server name. Cancel this operation?";
         String^ caption = "No Server Name Specified";
         MessageBoxButtons buttons = MessageBoxButtons::YesNo;
         System::Windows::Forms::DialogResult result;

         // Displays the MessageBox.
         result = MessageBox::Show( this, message, caption, buttons );
         if ( result == ::DialogResult::Yes )
         {
            // Closes the parent form.
            this->Close();
         }
      }
   }
private void validateUserEntry()
{
    // Checks the value of the text.
    if(serverName.Text.Length == 0)
    {
        // Initializes the variables to pass to the MessageBox.Show method.
        string message = "You did not enter a server name. Cancel this operation?";
     string caption = "Error Detected in Input";
        MessageBoxButtons buttons = MessageBoxButtons.YesNo;
        DialogResult result;

        // Displays the MessageBox.
        result = MessageBox.Show(message, caption, buttons);
        if (result == System.Windows.Forms.DialogResult.Yes)
        {
            // Closes the parent form.
            this.Close();
        }
    }
}
Private Sub ValidateUserEntry()
    ' Checks the value of the text.
    If ServerName.Text.Length = 0 Then

        ' Initializes variables to pass to the MessageBox.Show method.
        Dim Message As String = "You did not enter a server name. Cancel this operation?"
        Dim Caption As String = "Error Detected in Input"
        Dim Buttons As MessageBoxButtons = MessageBoxButtons.YesNo

        Dim Result As DialogResult

        'Displays the MessageBox
        Result = MessageBox.Show(Message, Caption, Buttons)

        ' Gets the result of the MessageBox display.
        If Result = System.Windows.Forms.DialogResult.Yes Then
            ' Closes the parent form.
            Me.Close()
        End If
    End If
End Sub

下面的代码示例演示如何向用户询问 "是" 或 "否" 问题, 并根据响应做出决定。The following code example shows how to ask the user a yes or no question and make a decision based on the response.

private:
   void Form1_FormClosing(Object^ sender, FormClosingEventArgs^ e)
   {
      // If the no button was pressed ...
      if ((MessageBox::Show(
         "Are you sure that you would like to close the form?", 
         "Form Closing", MessageBoxButtons::YesNo, 
         MessageBoxIcon::Question) == DialogResult::No))
      {
         // cancel the closure of the form.
         e->Cancel = true;
      }
   }

private void Form1_FormClosing(object sender, FormClosingEventArgs e)
{
    const string message =
        "Are you sure that you would like to close the form?";
    const string caption = "Form Closing";
    var result = MessageBox.Show(message, caption,
                                 MessageBoxButtons.YesNo,
                                 MessageBoxIcon.Question);

    // If the no button was pressed ...
    if (result == DialogResult.No)
    {
        // cancel the closure of the form.
        e.Cancel = true;
    }
}
Private Sub Form1_FormClosing( _
    ByVal sender As System.Object, _
    ByVal e As System.Windows.Forms.FormClosingEventArgs) _
    Handles MyBase.FormClosing

    Dim message As String = _
            "Are you sure that you would like to close the form?"
    Dim caption As String = "Form Closing"
    Dim result = MessageBox.Show(message, caption, _
                                 MessageBoxButtons.YesNo, _
                                 MessageBoxIcon.Question)

    ' If the no button was pressed ...
    If (result = DialogResult.No) Then
        ' cancel the closure of the form.
        e.Cancel = True
    End If
End Sub

注解

不能创建MessageBox类的新实例。You cannot create a new instance of the MessageBox class. 若要显示消息框, 请调用static方法MessageBox.ShowTo display a message box, call the static method MessageBox.Show. 消息框中显示的标题、消息、按钮和图标由传递给此方法的参数决定。The title, message, buttons, and icons displayed in the message box are determined by parameters that you pass to this method.

方法

Equals(Object)

确定指定的对象是否等于当前对象。Determines whether the specified object is equal to the current object.

(继承自 Object)
GetHashCode()

作为默认哈希函数。Serves as the default hash function.

(继承自 Object)
GetType()

获取当前实例的 TypeGets the Type of the current instance.

(继承自 Object)
MemberwiseClone()

创建当前 Object 的浅表副本。Creates a shallow copy of the current Object.

(继承自 Object)
Show(IWin32Window, String)

在指定对象的前面显示具有指定文本的消息框。Displays a message box in front of the specified object and with the specified text.

Show(IWin32Window, String, String)

在指定对象的前面显示具有指定文本和标题的消息框。Displays a message box in front of the specified object and with the specified text and caption.

Show(IWin32Window, String, String, MessageBoxButtons)

在指定对象的前面显示具有指定文本、标题和按钮的消息框。Displays a message box in front of the specified object and with the specified text, caption, and buttons.

Show(IWin32Window, String, String, MessageBoxButtons, MessageBoxIcon)

在指定对象的前面显示具有指定文本、标题、按钮和图标的消息框。Displays a message box in front of the specified object and with the specified text, caption, buttons, and icon.

Show(IWin32Window, String, String, MessageBoxButtons, MessageBoxIcon, MessageBoxDefaultButton)

在指定对象的前面显示具有指定文本、标题、按钮、图标和默认按钮的消息框。Displays a message box in front of the specified object and with the specified text, caption, buttons, icon, and default button.

Show(IWin32Window, String, String, MessageBoxButtons, MessageBoxIcon, MessageBoxDefaultButton, MessageBoxOptions)

在指定对象的前面显示具有指定文本、标题、按钮、图标、默认按钮和选项的消息框。Displays a message box in front of the specified object and with the specified text, caption, buttons, icon, default button, and options.

Show(IWin32Window, String, String, MessageBoxButtons, MessageBoxIcon, MessageBoxDefaultButton, MessageBoxOptions, String)

使用指定的帮助文件显示一个具有指定文本、标题、按钮、图标、默认按钮、选项和“帮助”按钮的消息框。Displays a message box with the specified text, caption, buttons, icon, default button, options, and Help button, using the specified Help file.

Show(IWin32Window, String, String, MessageBoxButtons, MessageBoxIcon, MessageBoxDefaultButton, MessageBoxOptions, String, HelpNavigator)

使用指定的帮助文件和 HelpNavigator 显示一个具有指定文本、标题、按钮、图标、默认按钮、选项和“帮助”按钮的消息框。Displays a message box with the specified text, caption, buttons, icon, default button, options, and Help button, using the specified Help file and HelpNavigator.

Show(IWin32Window, String, String, MessageBoxButtons, MessageBoxIcon, MessageBoxDefaultButton, MessageBoxOptions, String, HelpNavigator, Object)

使用指定的帮助文件、HelpNavigator 和帮助主题显示一个具有指定文本、标题、按钮、图标、默认按钮、选项和“帮助”按钮的消息框。Displays a message box with the specified text, caption, buttons, icon, default button, options, and Help button, using the specified Help file, HelpNavigator, and Help topic.

Show(IWin32Window, String, String, MessageBoxButtons, MessageBoxIcon, MessageBoxDefaultButton, MessageBoxOptions, String, String)

使用指定的帮助文件和帮助关键字显示一个具有指定文本、标题、按钮、图标、默认按钮、选项和“帮助”按钮的消息框。Displays a message box with the specified text, caption, buttons, icon, default button, options, and Help button, using the specified Help file and Help keyword.

Show(String)

显示具有指定文本的消息框。Displays a message box with specified text.

Show(String, String)

显示具有指定文本和标题的消息框。Displays a message box with specified text and caption.

Show(String, String, MessageBoxButtons)

显示具有指定文本、标题和按钮的消息框。Displays a message box with specified text, caption, and buttons.

Show(String, String, MessageBoxButtons, MessageBoxIcon)

显示具有指定文本、标题、按钮和图标的消息框。Displays a message box with specified text, caption, buttons, and icon.

Show(String, String, MessageBoxButtons, MessageBoxIcon, MessageBoxDefaultButton)

显示具有指定文本、标题、按钮、图标和默认按钮的消息框。Displays a message box with the specified text, caption, buttons, icon, and default button.

Show(String, String, MessageBoxButtons, MessageBoxIcon, MessageBoxDefaultButton, MessageBoxOptions)

显示具有指定文本、标题、按钮、图标、默认按钮和选项的消息框。Displays a message box with the specified text, caption, buttons, icon, default button, and options.

Show(String, String, MessageBoxButtons, MessageBoxIcon, MessageBoxDefaultButton, MessageBoxOptions, Boolean)

显示一个具有指定文本、标题、按钮、图标、默认按钮、选项和“帮助”按钮的消息框。Displays a message box with the specified text, caption, buttons, icon, default button, options, and Help button.

Show(String, String, MessageBoxButtons, MessageBoxIcon, MessageBoxDefaultButton, MessageBoxOptions, String)

使用指定的帮助文件显示一个具有指定文本、标题、按钮、图标、默认按钮、选项和“帮助”按钮的消息框。Displays a message box with the specified text, caption, buttons, icon, default button, options, and Help button, using the specified Help file.

Show(String, String, MessageBoxButtons, MessageBoxIcon, MessageBoxDefaultButton, MessageBoxOptions, String, HelpNavigator)

使用指定的帮助文件和 HelpNavigator 显示一个具有指定文本、标题、按钮、图标、默认按钮、选项和“帮助”按钮的消息框。Displays a message box with the specified text, caption, buttons, icon, default button, options, and Help button, using the specified Help file and HelpNavigator.

Show(String, String, MessageBoxButtons, MessageBoxIcon, MessageBoxDefaultButton, MessageBoxOptions, String, HelpNavigator, Object)

使用指定的帮助文件、HelpNavigator 和帮助主题显示一个具有指定文本、标题、按钮、图标、默认按钮、选项和“帮助”按钮的消息框。Displays a message box with the specified text, caption, buttons, icon, default button, options, and Help button, using the specified Help file, HelpNavigator, and Help topic.

Show(String, String, MessageBoxButtons, MessageBoxIcon, MessageBoxDefaultButton, MessageBoxOptions, String, String)

使用指定的帮助文件和帮助关键字显示一个具有指定文本、标题、按钮、图标、默认按钮、选项和“帮助”按钮的消息框。Displays a message box with the specified text, caption, buttons, icon, default button, options, and Help button, using the specified Help file and Help keyword.

ToString()

返回表示当前对象的字符串。Returns a string that represents the current object.

(继承自 Object)

适用于

另请参阅