Expression.TryCatchFinally(Expression, Expression, CatchBlock[]) Yöntem

Tanım

Ad Alanı:

System.Linq.Expressions

Bütünleştirilmiş Kod:

System.Linq.Expressions.dll

Kaynak:

TryExpression.cs

Herhangi bir TryExpression sayıda catch deyimi ve bir finally bloğu ile try bloğunu temsil eden bir oluşturur.

public:
 static System::Linq::Expressions::TryExpression ^ TryCatchFinally(System::Linq::Expressions::Expression ^ body, System::Linq::Expressions::Expression ^ finally, ... cli::array <System::Linq::Expressions::CatchBlock ^> ^ handlers);

public static System.Linq.Expressions.TryExpression TryCatchFinally (System.Linq.Expressions.Expression body, System.Linq.Expressions.Expression? finally, params System.Linq.Expressions.CatchBlock[]? handlers);

static member TryCatchFinally : System.Linq.Expressions.Expression * System.Linq.Expressions.Expression * System.Linq.Expressions.CatchBlock[] -> System.Linq.Expressions.TryExpression

Public Shared Function TryCatchFinally (body As Expression, finally As Expression, ParamArray handlers As CatchBlock()) As TryExpression

Parametreler

body

Expression

Try bloğunun gövdesi.

finally

Expression

Finally bloğunun gövdesi.

handlers

CatchBlock[]

Try bloğuyla ilişkilendirilecek catch deyimlerini temsil eden sıfır veya daha fazla CatchBlock ifade dizisi.

Döndürülenler

TryExpression

Oluşturulan TryExpression.

Örnekler

Aşağıdaki örnekte catch deyimi ve finally deyimi içeren bir TryExpression nesnenin nasıl oluşturulacağı gösterilmektedir.

// Add the following directive to the file.
// using System.Linq.Expressions;

// A TryExpression object that has a catch statement and a finally statement.
// The return types of the try block and all catch blocks must be the same.
TryExpression tryCatchExpr =
    Expression.TryCatchFinally(
        Expression.Block(
            Expression.Throw(Expression.Constant(new DivideByZeroException())),
            Expression.Constant("Try block")
        ),
        Expression.Call(typeof(Console).GetMethod("WriteLine", new Type[] { typeof(string) }), Expression.Constant("Finally block")),
        Expression.Catch(
            typeof(DivideByZeroException),
            Expression.Constant("Catch block")
        )
    );

// The following statement first creates an expression tree,
// then compiles it, and then runs it.
// If the exception is caught,
// the result of the TryExpression is the last statement
// of the corresponding catch statement.
Console.WriteLine(Expression.Lambda<Func<string>>(tryCatchExpr).Compile()());

// This code example produces the following output:
//
// Finally block
// Catch block

' Add the following directive to the file:
' Imports System.Linq.Expressions 

' A TryExpression object that has a catch statement and a finally statement.
' The return types of the try block and all catch blocks must be the same.
Dim tryCatchExpr As TryExpression =
    Expression.TryCatchFinally(
        Expression.Block(
            Expression.Throw(Expression.Constant(New DivideByZeroException())),
            Expression.Constant("Try block")
         ),
    Expression.Call(
        GetType(Console).GetMethod("WriteLine", New Type() {GetType(String)}),
        Expression.Constant("Finally block")
    ),
    Expression.Catch(
        GetType(DivideByZeroException),
        Expression.Constant("Catch block")
    )
)

' The following statement first creates an expression tree,
' then compiles it, and then runs it.
' If the exception is caught, 
' the result of the TryExpression is the last statement 
' of the corresponding catch statement.
Console.WriteLine(Expression.Lambda(Of Func(Of String))(tryCatchExpr).Compile()())

' This code example produces the following output:
'
' Finally block
' Catch block