Exception.ToString Exception.ToString Exception.ToString Exception.ToString Method

定义

创建并返回当前异常的字符串表示形式。Creates and returns a string representation of the current exception.

public:
 override System::String ^ ToString();
public override string ToString ();
override this.ToString : unit -> string
Public Overrides Function ToString () As String

返回

当前异常的字符串表示形式。A string representation of the current exception.

实现

示例

下面的示例会导致异常,并显示调用的结果ToString上该异常。The following example causes an exception and displays the result of calling ToString on that exception. 请注意,Exception.ToString的参数列表中出现的异常类实例时,方法隐式调用Console.WriteLine方法。Note that the Exception.ToString method is called implicitly when the Exception class instance appears in the argument list of the Console.WriteLine method.

using namespace System;

public ref class TestClass{};

int main()
{
   TestClass^ test = gcnew TestClass;
   array<Object^>^ objectsToCompare = { test, test->ToString(), 123,
                                        (123).ToString(), "some text",
                                        "Some Text" };
   String^ s = "some text";
   for each (Object^ objectToCompare in objectsToCompare) {
      try {
         Int32 i = s->CompareTo(objectToCompare);
         Console::WriteLine("Comparing '{0}' with '{1}': {2}",
                            s, objectToCompare, i);
      }
      catch (ArgumentException^ e) {
            Console::WriteLine("Bad argument: {0} (type {1})",
                              objectToCompare,
                              objectToCompare->GetType()->Name);
            Console::WriteLine("Exception information: {0}", e);
      }
      Console::WriteLine();
   }
}
// The example displays the following output:
//     Bad argument: TestClass (type TestClass)
//     Exception information: System.ArgumentException: Object must be of type String.
//        at System.String.CompareTo(Object value)
//        at Example.Main()
//     
//     Comparing 'some text' with 'TestClass': -1
//     
//     Bad argument: 123 (type Int32)
//     Exception information: System.ArgumentException: Object must be of type String.
//        at System.String.CompareTo(Object value)
//        at Example.Main()
//     
//     Comparing 'some text' with '123': 1
//     
//     Comparing 'some text' with 'some text': 0
//     
//     Comparing 'some text' with 'Some Text': -1
using System;

public class TestClass
{}

public class Example 
{
   public static void Main()
   {
      var test = new TestClass();
      Object[] objectsToCompare = { test, test.ToString(), 123,
                                    123.ToString(), "some text",
                                    "Some Text" };
      string s = "some text";
      foreach (var objectToCompare in objectsToCompare) {
         try {
            int i = s.CompareTo(objectToCompare);
            Console.WriteLine("Comparing '{0}' with '{1}': {2}",
                              s, objectToCompare, i);
         }
         catch (ArgumentException e) {
            Console.WriteLine("Bad argument: {0} (type {1})",
                              objectToCompare,
                              objectToCompare.GetType().Name);
            Console.WriteLine("Exception information: {0}", e);
         }
         Console.WriteLine();
      }
   }
}
// The example displays the following output:
//     Bad argument: TestClass (type TestClass)
//     Exception information: System.ArgumentException: Object must be of type String.
//        at System.String.CompareTo(Object value)
//        at Example.Main()
//     
//     Comparing 'some text' with 'TestClass': -1
//     
//     Bad argument: 123 (type Int32)
//     Exception information: System.ArgumentException: Object must be of type String.
//        at System.String.CompareTo(Object value)
//        at Example.Main()
//     
//     Comparing 'some text' with '123': 1
//     
//     Comparing 'some text' with 'some text': 0
//     
//     Comparing 'some text' with 'Some Text': -1
Public Class TestClass
End Class 

Public Class Example
   Public Shared Sub Main()
      Dim test As New TestClass()
      Dim objectsToCompare() As Object = { test, test.ToString(), 123,
                                           123.ToString(), "some text",
                                           "Some Text" }
      Dim s As String = "some text"
      For Each objectToCompare In objectsToCompare
         Try
            Dim i As Integer = s.CompareTo(objectToCompare)
            Console.WriteLine("Comparing '{0}' with '{1}': {2}",
                              s, objectToCompare, i)
         Catch e As ArgumentException
            Console.WriteLine("Bad argument: {0} (type {1})",
                              objectToCompare,
                              objectToCompare.GetType().Name)
            Console.WriteLine("Exception information: {0}", e)
         End Try
         Console.WriteLine()
      Next
   End Sub 
End Class 
' The example displays the following output:
'     Bad argument: TestClass (type TestClass)
'     Exception information: System.ArgumentException: Object must be of type String.
'        at System.String.CompareTo(Object value)
'        at Example.Main()
'     
'     Comparing 'some text' with 'TestClass': -1
'     
'     Bad argument: 123 (type Int32)
'     Exception information: System.ArgumentException: Object must be of type String.
'        at System.String.CompareTo(Object value)
'        at Example.Main()
'     
'     Comparing 'some text' with '123': 1
'     
'     Comparing 'some text' with 'some text': 0
'     
'     Comparing 'some text' with 'Some Text': -1

注解

ToString 返回用于为人所理解的当前异常的表示形式。ToString returns a representation of the current exception that is intended to be understood by humans. 当该异常包含区分区域性的数据,返回的字符串表示形式ToString所需的当前系统区域性考虑在内。Where the exception contains culture-sensitive data, the string representation returned by ToString is required to take into account the current system culture. 虽然没有返回字符串的确切格式要求,但它应尝试反映形式从用户的角度的对象的值。Although there are no exact requirements for the format of the returned string, it should attempt to reflect the value of the object as perceived by the user.

默认实现ToString获取引发当前异常、 消息、 调用的结果的类的名称ToString上的内部异常,并因调用Environment.StackTraceThe default implementation of ToString obtains the name of the class that threw the current exception, the message, the result of calling ToString on the inner exception, and the result of calling Environment.StackTrace. 如果任何这些成员为null,其值不包括在返回的字符串。If any of these members is null, its value is not included in the returned string.

如果没有任何错误消息或为空字符串 (""),则不返回任何错误消息。If there is no error message or if it is an empty string (""), then no error message is returned. 仅当它们不是返回的内部异常和堆栈跟踪名称nullThe name of the inner exception and the stack trace are returned only if they are not null.

此方法重写 Object.ToStringThis method overrides Object.ToString.

适用于