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ValueTypePropertyReference<TOperand, TResult> Class

Represents a property on a value type that can be used as an l-value in an expression.

System.Object
  System.Activities.Activity
    System.Activities.ActivityWithResult
      System.Activities.Activity<Location<TResult>>
        System.Activities.CodeActivity<Location<TResult>>
          System.Activities.Expressions.ValueTypePropertyReference<TOperand, TResult>

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

public sealed class ValueTypePropertyReference<TOperand, TResult> : CodeActivity<Location<TResult>>

Type Parameters

TOperand

The value type.

TResult

The property type.

The ValueTypePropertyReference<TOperand, TResult> type exposes the following members.

  NameDescription
Public methodValueTypePropertyReference<TOperand, TResult>Initializes a new instance of the ValueTypePropertyReference<TOperand, TResult> class.
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  NameDescription
Protected propertyCacheIdGets the identifier of the cache that is unique within the scope of the workflow definition. (Inherited from Activity.)
Public propertyDisplayNameGets or sets an optional friendly name that is used for debugging, validation, exception handling, and tracking. (Inherited from Activity.)
Public propertyIdGets an identifier that is unique in the scope of the workflow definition. (Inherited from Activity.)
Protected propertyImplementationVersionGets or sets the implementation version of the activity. (Inherited from CodeActivity<TResult>.)
Public propertyOperandLocationGets or sets the instance of the value type that contains the property.
Public propertyPropertyNameGets or sets the name of the property.
Public propertyResultGets or sets the result argument for the Activity<TResult>. (Inherited from Activity<TResult>.)
Public propertyResultTypeWhen implemented in a derived class, gets the type of an activity OutArgument. (Inherited from ActivityWithResult.)
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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 methodShouldSerializeDisplayNameIndicates whether the DisplayName property should be serialized. (Inherited from Activity.)
Public methodToStringReturns a String that contains the Id and DisplayName of the Activity. (Inherited from Activity.)
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The following code example uses ValueTypePropertyReference<TOperand, TResult> in an Assign activity to assign a string value to a property and prints the property value to the console. The Assign activity is equivalent to the following statement when using the struct defined in the following example: myStructVariable.AProperty = "Hello";.

NoteNote

Instead of instantiating the ValueTypePropertyReference<TOperand, TResult> l-value expression activity directly, it is strongly recommended that you call ConvertReference<TResult>, which provides a higher level of abstraction and enables you to implement your workflow more intuitively.

    // Define a struct with a property named AProperty.
    struct StructWithProperty
    {
        public string AProperty { get; set; }
    }

    public static void ValueTypePropertyReferenceSample()
    {
        // Create a variable of type StructWithProperty to store the property.
        var swpvar = new Variable<StructWithProperty>("swpvar", new StructWithProperty());

        // Create the top-level activity to be invoked later.
        Activity myActivity = new Sequence
        {
            Variables = { swpvar },
            Activities = 
            {                    
                // Create an Assign activity for a property named AProperty.
                new Assign<string>
                {
                    To = new ValueTypePropertyReference<StructWithProperty, string>
                    {
                        OperandLocation = swpvar,
                        PropertyName = "AProperty",
                    },
                    // Assign a string literal to AProperty.
                    Value = "Hello",
                },
                // Create a WriteLine activity to write the value of AProperty to the console.
                new WriteLine()
                {
                    Text = ExpressionServices.Convert<string>(ctx => swpvar.Get(ctx).AProperty),
                }
            }
        };

        // Invoke the Sequence activity.
        WorkflowInvoker.Invoke(myActivity);
    }

.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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