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TryCatchFinally Method
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Expression.TryCatchFinally Method

Creates a TryExpression representing a try block with any number of catch statements and a finally block.

Namespace:  System.Linq.Expressions
Assemblies:   System.Core (in System.Core.dll)
  System.Linq.Expressions (in System.Linq.Expressions.dll)

public static TryExpression TryCatchFinally(
	Expression body,
	Expression finally,
	params CatchBlock[] handlers
)

Parameters

body
Type: System.Linq.Expressions.Expression

The body of the try block.

finally
Type: System.Linq.Expressions.Expression

The body of the finally block.

handlers
Type: System.Linq.Expressions.CatchBlock[]

The array of zero or more CatchBlock expressions representing the catch statements to be associated with the try block.

The following example demonstrates how to create a TryExpression object that contains a catch statement and a finally statement.

// 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

.NET Framework

Supported in: 4.6, 4.5, 4

.NET Framework Client Profile

Supported in: 4

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone Silverlight 8.1, Windows Phone Silverlight 8

Portable Class Library

Supported in: Portable Class Library
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