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Catch<TException> Class

Contains the actions to be executed after an exception is raised in the corresponding Try block of a TryCatchFinally activity.

System.Object
  System.Activities.Statements.Catch
    System.Activities.Statements.Catch<TException>

Namespace:  System.Activities.Statements
Assembly:  System.Activities (in System.Activities.dll)

[ContentPropertyAttribute("Action")]
public sealed class Catch<TException> : Catch 
where TException : Exception

Type Parameters

TException

The type of exception that the Catch<TException> block is handling.

The Catch<TException> type exposes the following members.

  NameDescription
Public methodCatch<TException>Creates a new instance of the Catch<TException> class.
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  NameDescription
Public propertyActionThe handler for the exception being caught.
Public propertyExceptionTypeThe type of exception that the Catch block is handling. (Overrides Catch.ExceptionType.)
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  NameDescription
Public methodEquals(Object)Determines whether the specified object is equal to the current object. (Inherited from Object.)
Public methodGetHashCodeServes as the default hash function. (Inherited from Object.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)
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Once placed in the designer, Catch activities cannot be reordered in the designer. To reorder the collection of Catch activities, either delete and re-add them in the correct order, or use the xaml (code) view for the workflow.

The following code sample demonstrates creating a Catch<TException> activity. This example is from the Fault Handling in a Flowchart Activity Using TryCatch sample.

FlowStep mwkStep = new FlowStep
{
    Action = new TryCatch
    {
        DisplayName = "Try/Catch for Divide By Zero Exception",
        Try = new Assign
        {
            DisplayName = "discount = 15 + (1 - 1/numberOfKids)*10",
            To = new OutArgument<double>(discount),
            Value = new InArgument<double>((ctx) => (15 + (1 - 1 / numberOfKids.Get(ctx)) * 10))
        },
        Catches = 
        {
             new Catch<System.DivideByZeroException>
             {
                 Action = new ActivityAction<System.DivideByZeroException>
                 {
                     Argument = ex,
                     DisplayName = "ActivityAction - DivideByZeroException",
                     Handler =
                         new Sequence
                         {
                             DisplayName = "Divide by Zero Exception Workflow",
                             Activities =
                             {
                                new WriteLine() 
                                { 
                                    DisplayName = "WriteLine: DivideByZeroException",
                                    Text = "DivideByZeroException: Promo code is MWK - but number of kids = 0" 
                                },
                                new Assign<double>
                                {
                                    DisplayName = "Exception - discount = 0", 
                                    To = discount,
                                    Value = new InArgument<double>(0)
                                }
                             }
                         }
                 }
             }
        }
    },
    Next = flowDecision
};

.NET Framework

Supported in: 4.5, 4

.NET Framework Client Profile

Supported in: 4

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
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