Exception.ToString 方法
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
建立並傳回目前例外狀況的字串表示。
public:
override System::String ^ ToString();
public override string ToString ();
override this.ToString : unit -> string
Public Overrides Function ToString () As String
傳回
目前例外狀況的字串表示。
實作
範例
下列範例會造成例外狀況,並顯示在該例外狀況上呼叫 ToString 的結果。 請注意, Exception.ToString 當 Exception 類別實例出現在方法的 Console.WriteLine 引數清單中時,會隱含呼叫 方法。
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
open System
type TestClass() = class end
let test = TestClass()
let objectsToCompare: obj[] =
[| test; test.ToString(); 123
string 123; "some text"
"Some Text" |]
let s = "some text"
for objectToCompare in objectsToCompare do
try
let i = s.CompareTo objectToCompare
printfn $"Comparing '{s}' with '{objectToCompare}': {i}"
with :? ArgumentException as e ->
printfn $"Bad argument: {objectToCompare} (type {objectToCompare.GetType().Name})"
printfn $"Exception information: {e}"
printfn ""
// The example displays the following output:
// Bad argument: Example+TestClass (type TestClass)
// Exception information: System.ArgumentException: Object must be of type String.
// at System.String.CompareTo(Object value)
// at <StartupCode$fs>.$Example.main@()
//
// Comparing 'some text' with 'Example+TestClass': -1
//
// Bad argument: 123 (type Int32)
// Exception information: System.ArgumentException: Object must be of type String.
// at System.String.CompareTo(Object value)
// at <StartupCode$fs>.$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
備註
ToString 會傳回目前例外狀況的標記法,此例外狀況旨在供人類瞭解。 如果例外狀況包含區分文化特性的資料,則需要傳 ToString
回的字串標記法,才能考慮目前的系統文化特性。 雖然傳回字串的格式沒有確切的需求,但應該嘗試反映使用者所察覺的物件值。
的預設實 ToString 作會取得擲回目前例外狀況的類別名稱、訊息、在內部例外狀況上呼叫 ToString 的結果,以及呼叫 Environment.StackTrace 的結果。 如果其中任一成員為 null
,則傳回的字串中不包含其值。
如果沒有錯誤訊息,或它是空字串 (「」) ,則不會傳回任何錯誤訊息。 只有在不是 時 null
,才會傳回內部例外狀況和堆疊追蹤的名稱。
這個方法會覆寫 Object.ToString。