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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
Assembly:  System.Core (in System.Core.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.
outputBlock.Text += Expression.Lambda<Func<string>>(tryCatchExpr).Compile()() + "\n";

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


Silverlight

Supported in: 5, 4

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

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