对异常消息框编程
可以使用应用程序中的异常消息框，它与 MessageBox 类相比，可以大大提高对消息传送的控制。 有关详细信息，请参阅异常消息框编程。 有关如何获取和部署异常消息框 .dll 的信息，请参阅部署异常消息框应用程序。
过程
通过使用异常消息框处理异常
将托管代码项目中的某个引用添加到 Microsoft.ExceptionMessageBox.dll 程序集。
（可选）添加 using (C#) 或 Imports (Microsoft Visual Basic .NET) 指令以使用 Microsoft.SqlServer.MessageBox 命名空间。
创建 try-catch 块处理预期异常。
在 catch 块中，创建 ExceptionMessageBox 类的实例。 传递由 try-catch 块处理的 Exception 对象。
（可选）为 ExceptionMessageBox 设置下列一个或多个属性：
Buttons - ExceptionMessageBoxButtons 枚举，用于指定要在异常消息框中显示的按钮。
DefaultButton - ExceptionMessageBoxDefaultButton 枚举，用于指定异常消息框的默认按钮。
Options - ExceptionMessageBoxOptions 枚举，用于控制异常消息框的其他行为。
Symbol - ExceptionMessageBoxSymbol 枚举，用于指定要在异常消息框中显示的符号。
调用 Show 方法。 传递异常消息框所属的父窗口。
（可选）如果需要确定用户单击的按钮，请注明返回的 DialogResult 枚举值。
显示没有异常的异常消息框
将托管代码项目中的某个引用添加到 Microsoft.ExceptionMessageBox.dll 程序集。
（可选）添加 using (C#) 或 Imports (Visual Basic .NET) 指令以使用 Microsoft.SqlServer.MessageBox 命名空间。
创建 ExceptionMessageBox 类的实例。 将消息文本作为 String 值传递。
（可选）为 ExceptionMessageBox 设置下列一个或多个属性：
Buttons - ExceptionMessageBoxButtons 枚举，用于指定要在异常消息框中显示的按钮。
Caption - 异常消息框的对话框标题。
DefaultButton - ExceptionMessageBoxDefaultButton 枚举，用于指定异常消息框对话框的默认按钮。
Options - ExceptionMessageBoxOptions 枚举，用于控制异常消息框的其他行为。
Symbol - ExceptionMessageBoxSymbol 枚举，用于指定要在异常消息框中显示的符号。
调用 Show 方法。 传递异常消息框所属的父窗口。
（可选）如果需要确定用户单击的按钮，请注明返回的 DialogResult 枚举值。
显示具有自定义按钮的异常消息框
将托管代码项目中的某个引用添加到 Microsoft.ExceptionMessageBox.dll 程序集。
（可选）添加 using (C#) 或 Imports (Visual Basic .NET) 指令以使用 Microsoft.SqlServer.MessageBox 命名空间。
按以下两种方式之一创建 ExceptionMessageBox 类的实例：
为 Buttons 设置以下值之一：
AbortRetryIgnore - 显示**“中止”、“重试”和“忽略”**按钮。
Custom - 显示自定义按钮。
OK - 显示**“确定”**按钮。
OKCancel - 显示**“确定”和“取消”**按钮。
RetryCancel - 显示**“重试”和“取消”**按钮。
YesNo - 显示**“是”和“否”**按钮。
YesNoCancel - 显示**“是”、“否”和“取消”**按钮。
（可选）如果使用自定义按钮，请调用 SetButtonText 方法的重载之一以指定最多五个自定义按钮的文本。
调用 Show 方法。 传递异常消息框所属的父窗口。
（可选）如果需要确定用户单击的按钮，请注明返回的 DialogResult 枚举值。 如果使用自定义按钮，请注明 CustomDialogResult 属性的 ExceptionMessageBoxDialogResult 值以确定用户单击的自定义按钮。
允许用户决定是否要显示异常消息框
将托管代码项目中的某个引用添加到 Microsoft.ExceptionMessageBox.dll 程序集。
（可选）添加 using (C#) 或 Imports (Visual Basic .NET) 指令以使用 Microsoft.SqlServer.MessageBox 命名空间。
按以下两种方式之一创建 ExceptionMessageBox 类的实例：
将 ShowCheckbox 属性设置为 true。
（可选）指定请用户决定以后是否还为 CheckboxText 显示异常消息框的文本。 默认文本为“不再显示此消息”。
如果需要仅在应用程序执行期间保留用户的决定，请将 IsCheckboxChecked 的值设置为全局 Boolean 变量。 在创建异常消息框的实例前计算此值。
如果需要永久存储用户的决定，请执行以下操作：
调用 CreateSubKey(String) 方法以打开您的应用程序使用的自定义注册表项，然后将 CheckboxRegistryKey 设置为返回的 RegistryKey 对象。
将 CheckboxRegistryValue 设置为使用的注册表值的名称。
将 CheckboxRegistryMeansDoNotShowDialog 设置为 true。
调用 Show 方法。 计算指定的注册表项，仅当注册表项中存储的数据为 0 时才显示异常消息框。 如果显示对话框且用户在单击按钮前选中复选框，则注册表项中的数据设置为 1。
示例
以下示例使用只具有**“确定”**按钮的异常消息框，用于显示某应用程序异常的信息，该信息包括处理的异常以及其他应用程序特定信息。
try
{
// Do something that may generate an exception.
throw new ApplicationException("An error has occured");
}
catch (ApplicationException ex)
{
// Define a new top-level error message.
string str = "The action failed.";
// Add the new top-level message to the handled exception.
ApplicationException exTop = new ApplicationException(str, ex);
exTop.Source = this.Text;
// Show an exception message box with an OK button (the default).
ExceptionMessageBox box = new ExceptionMessageBox(exTop);
box.Show(this);
}
Try
' Do something that may generate an exception.
Throw New ApplicationException("An error has occured")
Catch ex As ApplicationException
' Define a new top-level error message.
Dim str As String = "The action failed."
' Add the new top-level message to the handled exception.
Dim exTop As ApplicationException = New ApplicationException(str, ex)
exTop.Source = Me.Text
' Show an exception message box with an OK button (the default).
Dim box As ExceptionMessageBox = New ExceptionMessageBox(exTop)
box.Show(Me)
End Try
以下示例使用一个异常消息框，该框具有供用户选择的**“是”和“否”**按钮。
// Define the message and caption to display.
string str = @"Are you sure you want to delete file 'c:\somefile.txt'?";
string caption = "Confirm File Deletion";
// Show the exception message box with Yes and No buttons.
ExceptionMessageBox box = new ExceptionMessageBox(str,
caption, ExceptionMessageBoxButtons.YesNo,
ExceptionMessageBoxSymbol.Question,
ExceptionMessageBoxDefaultButton.Button2);
if (DialogResult.Yes == box.Show(this))
{
// Delete the file.
}
' Define the message and caption to display.
Dim str As String = "Are you sure you want to delete file 'c:\somefile.txt'?"
Dim caption As String = "Confirm File Deletion"
' Show the exception message box with Yes and No buttons.
Dim box As ExceptionMessageBox = New ExceptionMessageBox(str, _
caption, ExceptionMessageBoxButtons.YesNo, _
ExceptionMessageBoxSymbol.Question, _
ExceptionMessageBoxDefaultButton.Button2)
If Windows.Forms.DialogResult.Yes = box.Show(Me) Then
' Delete the file.
End If
以下示例使用具有自定义按钮的异常消息框。
try
{
// Do something that may cause an exception.
throw new ApplicationException("An error has occured");
}
catch (ApplicationException ex)
{
string str = "Action failed. What do you want to do?";
ApplicationException exTop = new ApplicationException(str, ex);
exTop.Source = this.Text;
// Show the exception message box with three custom buttons.
ExceptionMessageBox box = new ExceptionMessageBox(exTop);
// Set the names of the three custom buttons.
box.SetButtonText("Skip", "Retry", "Stop Processing");
// Set the Retry button as the default.
box.DefaultButton = ExceptionMessageBoxDefaultButton.Button2;
box.Symbol = ExceptionMessageBoxSymbol.Question;
box.Buttons = ExceptionMessageBoxButtons.Custom;
box.Show(this);
// Do something, depending on the button that the user clicks.
switch (box.CustomDialogResult)
{
case ExceptionMessageBoxDialogResult.Button1:
// Skip action
break;
case ExceptionMessageBoxDialogResult.Button2:
// Retry action
break;
case ExceptionMessageBoxDialogResult.Button3:
// Stop processing action
break;
}
}
Try
' Do something that may cause an exception.
Throw New ApplicationException("An error has occured")
Catch ex As ApplicationException
Dim str As String = "Action failed. What do you want to do?"
Dim exTop As ApplicationException = New ApplicationException(str, ex)
exTop.Source = Me.Text
' Show the exception message box with three custom buttons.
Dim box As ExceptionMessageBox = New ExceptionMessageBox(exTop)
' Set the names of the three custom buttons.
box.SetButtonText("Skip", "Retry", "Stop Processing")
' Set the Retry button as the default.
box.DefaultButton = ExceptionMessageBoxDefaultButton.Button2
box.Symbol = ExceptionMessageBoxSymbol.Question
box.Buttons = ExceptionMessageBoxButtons.Custom
box.Show(Me)
' Do something, depending on the button that the user clicks.
Select Case box.CustomDialogResult
Case ExceptionMessageBoxDialogResult.Button1
' Skip action
Case ExceptionMessageBoxDialogResult.Button2
' Retry action
Case ExceptionMessageBoxDialogResult.Button3
' Stop processing action
End Select
End Try
以下示例使用复选框来确定是否显示异常消息框。
try
{
// Do something that may cause an exception.
throw new ApplicationException("An error has occured.");
}
catch (ApplicationException ex)
{
string str = "The action failed.";
ApplicationException exTop = new ApplicationException(str, ex);
exTop.Source = this.Text;
// Show a message box if the global variable is true.
if (alwaysShow)
{
ExceptionMessageBox box = new ExceptionMessageBox(exTop);
box.ShowCheckBox = true;
box.IsCheckBoxChecked = true;
box.CheckBoxText = "Always show this message";
box.Show(this);
// Set the global variable.
alwaysShow = box.IsCheckBoxChecked;
}
}
Try
' Do something that may cause an exception.
Throw New ApplicationException("An error has occured.")
Catch ex As ApplicationException
Dim str As String = "The action failed."
Dim exTop As ApplicationException = New ApplicationException(str, ex)
exTop.Source = Me.Text
' Show a message box if the global variable is true.
If alwaysShow Then
Dim box As ExceptionMessageBox = New ExceptionMessageBox(exTop)
box.ShowCheckBox = True
box.IsCheckBoxChecked = True
box.CheckBoxText = "Always show this message"
box.Show(Me)
' Set the global variable.
alwaysShow = box.IsCheckBoxChecked
End If
End Try
以下示例使用复选框和注册表项来确定是否显示异常消息框。
try
{
// Do something that could generate an exception.
throw new ApplicationException("An error has occured.");
}
catch (ApplicationException ex)
{
string str = "The action failed. Do you want to continue?";
ApplicationException exTop = new ApplicationException(str, ex);
exTop.Source = this.Text;
// Show a message box with Yes and No buttons
ExceptionMessageBox box = new ExceptionMessageBox(exTop,
ExceptionMessageBoxButtons.YesNo,
ExceptionMessageBoxSymbol.Question,
ExceptionMessageBoxDefaultButton.Button2);
// Enable the check box.
box.ShowCheckBox = true;
// Define the registry key to use.
box.CheckBoxRegistryKey =
Microsoft.Win32.Registry.CurrentUser.CreateSubKey(
@"Software\TestApp");
box.CheckBoxRegistryValue = "DontShowActionFailedMessage";
box.CheckBoxRegistryMeansDoNotShowDialog = true;
box.DefaultDialogResult = DialogResult.Yes;
// The message box won�t be displayed if the
// "DontShowActionFailedMessage" value of the registry key
// contains a non-zero value.
if (box.Show(this) == DialogResult.No)
{
// Do something if the user clicks the No button.
this.Close();
}
}
Try
' Do something that could generate an exception.
Throw New ApplicationException("An error has occured.")
Catch ex As ApplicationException
Dim str As String = "The action failed. Do you want to continue?"
Dim exTop As ApplicationException = New ApplicationException(str, ex)
exTop.Source = Me.Text
' Show a message box with Yes and No buttons
Dim box As ExceptionMessageBox = New ExceptionMessageBox(exTop, _
ExceptionMessageBoxButtons.YesNo, _
ExceptionMessageBoxSymbol.Question, _
ExceptionMessageBoxDefaultButton.Button2)
' Enable the check box.
box.ShowCheckBox = True
' Define the registry key to use.
box.CheckBoxRegistryKey = _
Microsoft.Win32.Registry.CurrentUser.CreateSubKey( _
"Software\TestApp")
box.CheckBoxRegistryValue = "DontShowActionFailedMessage"
box.CheckBoxRegistryMeansDoNotShowDialog = True
box.DefaultDialogResult = Windows.Forms.DialogResult.Yes
' The message box won�t be displayed if the
' "DontShowActionFailedMessage" value of the registry key
' contains a non-zero value.
If box.Show(Me) = Windows.Forms.DialogResult.No Then
' Do something if the user clicks the No button.
Me.Close()
End If
End Try
以下示例使用异常消息框来显示对排除故障或调试有帮助的其他信息。
try
{
// Do something that you don't expect to generate an exception.
throw new ApplicationException("Failed to connect to the server.");
}
catch (ApplicationException ex)
{
string str = "An unexpected error occurred. Please call Helpdesk.";
ApplicationException exTop = new ApplicationException(str, ex);
exTop.Source = this.Text;
// Information in the Data property of an exception that has a name
// beginning with "HelpLink.Advanced" is shown when the user
// clicks the Advanced Information button of the exception message
// box dialog box.
exTop.Data.Add("AdvancedInformation.FileName", "application.dll");
exTop.Data.Add("AdvancedInformation.FilePosition", "line 355");
exTop.Data.Add("AdvancedInformation.UserContext", "single user mode");
// Show the exception message box with additional information that
// is helpful when a user calls technical support.
ExceptionMessageBox box = new ExceptionMessageBox(exTop);
box.Show(this);
}
Try
' Do something that you don't expect to generate an exception.
Throw New ApplicationException("Failed to connect to the server.")
Catch ex As ApplicationException
Dim str As String = "An unexpected error occurred. Please call Helpdesk."
Dim exTop As ApplicationException = New ApplicationException(str, ex)
exTop.Source = Me.Text
' Information in the Data property of an exception that has a name
' beginning with "HelpLink.Advanced" is shown when the user
' clicks the Advanced Information button of the exception message
' box dialog box.
exTop.Data.Add("AdvancedInformation.FileName", "application.dll")
exTop.Data.Add("AdvancedInformation.FilePosition", "line 355")
exTop.Data.Add("AdvancedInformation.UserContext", "single user mode")
' Show the exception message box with additional information that
' is helpful when a user calls technical support.
Dim box As ExceptionMessageBox = New ExceptionMessageBox(exTop)
box.Show(Me)
End Try