如何：并行承载多个版本的工作流

项目
04/07/2023

WorkflowIdentity 为工作流应用程序开发人员提供了一种将名称和版本与工作流定义关联的方法，这种方法还可用于将此信息与持久化工作流实例相关联。工作流应用程序开发人员可以使用这些标识信息，为一些情景（如并行执行一个工作流定义的多个版本）提供支持，并为其他功能（如动态更新）提供基础。该教程中的此步骤演示了如何使用 WorkflowIdentity 来同时承载多个版本的工作流。

本主题内容

在该教程的此步骤中，工作流中的 WriteLine 活动已得到修改以提供其他信息，并且添加了一个新的 WriteLine 活动。将存储原始工作流程序集的副本，并更新主机应用程序以便其可同时在原始工作流和更新后的工作流中运行。

注意

在执行本主题中的步骤之前，请运行该应用程序，启动每个类型的多个工作流，并针对每个工作流进行一个或两个猜测。在此步骤和下一步骤如何：更新正在运行的工作流实例的定义中，将使用这些持久化工作流。

制作 NumberGuessWorkflowActivities 项目的副本

在 Visual Studio 2012 中打开 WF45GettingStartedTutorial 解决方案（如果其尚未打开）。
按 CTRL+SHIFT+B 生成解决方案。
关闭 WF45GettingStartedTutorial 解决方案。
打开 Windows 资源管理器并定位到该教程解决方案文件和项目文件夹所在的文件夹。
在 NumberGuessWorkflowHost 和 NumberGuessWorkflowActivities 所在的同一文件夹中创建名为 PreviousVersions 的新文件夹。此文件夹用于放置包含在后续教程步骤中使用的不同版本工作流的程序集。
定位到“NumberGuessWorkflowActivities\bin\debug”文件夹（或“bin\release”，具体取决于项目设置）。复制 NumberGuessWorkflowActivities.dll，然后将其粘贴到 PreviousVersions 文件夹中。
将 PreviousVersions 文件夹中的 NumberGuessWorkflowActivities.dll 重命名为 NumberGuessWorkflowActivities_v1.dll。

注意

本主题中的步骤演示了一种对用于包含多个版本的工作流的程序集进行管理的方法。也可以使用其他方法，例如，对程序集进行强命名，并在全局程序集缓冲中注册这些程序集。
在与 NumberGuessWorkflowHost、NumberGuessWorkflowActivities 以及新添加的 PreviousVersions 文件夹所在的同一文件夹中创建一个名为 NumberGuessWorkflowActivities_du 的新文件夹，并将 NumberGuessWorkflowActivities 文件夹中的所有文件和子文件夹复制到新的 NumberGuessWorkflowActivities_du 文件夹中。如何：更新正在运行的工作流实例的定义中使用了项目针对初始版本活动的此备份副本。
在 Visual Studio 2012 中重新打开 WF45GettingStartedTutorial 解决方案。

更新工作流

在本节中，将会更新工作流定义。将会更新针对用户猜测提供反馈的两个 WriteLine 活动，并添加一个新的 WriteLine 活动，此活动提供猜测了数字之后有关该游戏的其他信息。

更新 StateMachine 工作流

在解决方案资源管理器中的“NumberGuessWorkflowActivities”项目下面，双击“StateMachineNumberGuessWorkflow.xaml”。
双击状态机上的“Guess Incorrect”转换。

更新 Text 活动中最左侧 WriteLine 的 If。

Guess & " is too low."

Guess + " is too low."

更新 Text 活动中最右侧 WriteLine 的 If。

Guess & " is too high."

Guess + " is too high."

通过单击工作流设计器顶部的痕迹显示中的“StateMachine”，返回到工作流设计器中的整体状态机视图。
双击状态机上的“Guess Correct”转换。
拖动“工具箱”的“基元”部分中的一个“WriteLine”活动，然后将其放置在该转换的“在此处放置操作活动”标签上。

在 Text 属性框中键入以下表达式。

Guess & " is correct. You guessed it in " & Turns & " turns."

Guess + " is correct. You guessed it in " + Turns + " turns."

更新 Flowchart 工作流

在解决方案资源管理器中的“NumberGuessWorkflowActivities”项目下面，双击“FlowchartNumberGuessWorkflow.xaml”。

更新最左侧 Text 活动的 WriteLine。

Guess & " is too low."

Guess + " is too low."

更新最右侧 Text 活动的 WriteLine。

Guess & " is too high."

Guess + " is too high."

拖动“工具箱”的“基元”部分中的一个“WriteLine”活动，然后将其放置在最右侧 FlowDecision 的 True 操作的放置点上。 WriteLine 活动将添加到流程图并链接到 True 的 FlowDecision 操作。

在 Text 属性框中键入以下表达式。

Guess & " is correct. You guessed it in " & Turns & " turns."

Guess + " is correct. You guessed it in " + Turns + " turns."

更新 Sequential 工作流

在解决方案资源管理器中的“NumberGuessWorkflowActivities”项目下面，双击“SequentialNumberGuessWorkflow.xaml”。

更新 Text 活动中最左侧 WriteLine 的 If。

Guess & " is too low."

Guess + " is too low."

更新 Text 活动中最右侧 WriteLine 活动的 If。
```
Guess & " is too high."
```
```
Guess + " is too high."
```
拖动“工具箱”的“基元”部分中的一个“WriteLine”活动，然后将其放置在“DoWhile”活动的后面，以便让“WriteLine”称为根 Sequence 活动中的最终活动。

在 Text 属性框中键入以下表达式。

Guess & " is correct. You guessed it in " & Turns & " turns."

Guess + " is correct. You guessed it in " + Turns + " turns."

更新 WorkflowVersionMap 以包括以前的工作流版本

右键单击“NumberGuessWorkflowHost”项目下的“WorkflowVersionMap.cs”（或“WorkflowVersionMap.vb”），将其打开。
向包含其他 using（或 Imports）语句的文件的顶部添加以下 using（或 Imports）语句。
```
Imports System.Reflection
Imports System.IO
```
```
using System.Reflection;
using System.IO;
```

紧接在现有的三个工作流标识声明下面添加三个新工作流标识。这些新的 v1 工作流标识用于为在进行更新前启动的工作流提供正确的工作流定义。

'Current version identities.
Public StateMachineNumberGuessIdentity As WorkflowIdentity
Public FlowchartNumberGuessIdentity As WorkflowIdentity
Public SequentialNumberGuessIdentity As WorkflowIdentity

'v1 Identities.
Public StateMachineNumberGuessIdentity_v1 As WorkflowIdentity
Public FlowchartNumberGuessIdentity_v1 As WorkflowIdentity
Public SequentialNumberGuessIdentity_v1 As WorkflowIdentity

// Current version identities.
static public WorkflowIdentity StateMachineNumberGuessIdentity;
static public WorkflowIdentity FlowchartNumberGuessIdentity;
static public WorkflowIdentity SequentialNumberGuessIdentity;

// v1 identities.
static public WorkflowIdentity StateMachineNumberGuessIdentity_v1;
static public WorkflowIdentity FlowchartNumberGuessIdentity_v1;
static public WorkflowIdentity SequentialNumberGuessIdentity_v1;

在 WorkflowVersionMap 构造函数中，将三个当前工作流标识的 Version 属性更新为 2.0.0.0。

'Add the current workflow version identities.
StateMachineNumberGuessIdentity = New WorkflowIdentity With
{
    .Name = "StateMachineNumberGuessWorkflow",
    .Version = New Version(2, 0, 0, 0)
}

FlowchartNumberGuessIdentity = New WorkflowIdentity With
{
    .Name = "FlowchartNumberGuessWorkflow",
    .Version = New Version(2, 0, 0, 0)
}

SequentialNumberGuessIdentity = New WorkflowIdentity With
{
    .Name = "SequentialNumberGuessWorkflow",
    .Version = New Version(2, 0, 0, 0)
}

map.Add(StateMachineNumberGuessIdentity, New StateMachineNumberGuessWorkflow())
map.Add(FlowchartNumberGuessIdentity, New FlowchartNumberGuessWorkflow())
map.Add(SequentialNumberGuessIdentity, New SequentialNumberGuessWorkflow())

// Add the current workflow version identities.
StateMachineNumberGuessIdentity = new WorkflowIdentity
{
    Name = "StateMachineNumberGuessWorkflow",
    // Version = new Version(1, 0, 0, 0),
    Version = new Version(2, 0, 0, 0)
};

FlowchartNumberGuessIdentity = new WorkflowIdentity
{
    Name = "FlowchartNumberGuessWorkflow",
    // Version = new Version(1, 0, 0, 0),
    Version = new Version(2, 0, 0, 0)
};

SequentialNumberGuessIdentity = new WorkflowIdentity
{
    Name = "SequentialNumberGuessWorkflow",
    // Version = new Version(1, 0, 0, 0),
    Version = new Version(2, 0, 0, 0)
};

map.Add(StateMachineNumberGuessIdentity, new StateMachineNumberGuessWorkflow());
map.Add(FlowchartNumberGuessIdentity, new FlowchartNumberGuessWorkflow());
map.Add(SequentialNumberGuessIdentity, new SequentialNumberGuessWorkflow());

向字典添加当前版本的工作流的代码使用项目中引用的当前版本，因此，无需对初始化工作流定义的代码进行更新。

紧接在向字典添加当前版本的代码的后面添加以下代码。

'Initialize the previous workflow version identities.
StateMachineNumberGuessIdentity_v1 = New WorkflowIdentity With
{
    .Name = "StateMachineNumberGuessWorkflow",
    .Version = New Version(1, 0, 0, 0)
}

FlowchartNumberGuessIdentity_v1 = New WorkflowIdentity With
{
    .Name = "FlowchartNumberGuessWorkflow",
    .Version = New Version(1, 0, 0, 0)
}

SequentialNumberGuessIdentity_v1 = New WorkflowIdentity With
{
    .Name = "SequentialNumberGuessWorkflow",
    .Version = New Version(1, 0, 0, 0)
}

// Initialize the previous workflow version identities.
StateMachineNumberGuessIdentity_v1 = new WorkflowIdentity
{
    Name = "StateMachineNumberGuessWorkflow",
    Version = new Version(1, 0, 0, 0)
};

FlowchartNumberGuessIdentity_v1 = new WorkflowIdentity
{
    Name = "FlowchartNumberGuessWorkflow",
    Version = new Version(1, 0, 0, 0)
};

SequentialNumberGuessIdentity_v1 = new WorkflowIdentity
{
    Name = "SequentialNumberGuessWorkflow",
    Version = new Version(1, 0, 0, 0)
};

这些工作流标识与相应工作流定义的初始版本相关联。

接下来，加载包含初始版本的工作流定义的程序集，然后创建相应工作流定义，并将这些定义添加到字典。

'Add the previous version workflow identities to the dictionary along with
'the corresponding workflow definitions loaded from the v1 assembly.
'Assembly.LoadFile requires an absolute path so convert this relative path
'to an absolute path.
Dim v1AssemblyPath As String = "..\..\..\PreviousVersions\NumberGuessWorkflowActivities_v1.dll"
v1AssemblyPath = Path.GetFullPath(v1AssemblyPath)
Dim v1Assembly As Assembly = Assembly.LoadFile(v1AssemblyPath)

map.Add(StateMachineNumberGuessIdentity_v1,
    v1Assembly.CreateInstance("NumberGuessWorkflowActivities.StateMachineNumberGuessWorkflow"))

map.Add(SequentialNumberGuessIdentity_v1,
    v1Assembly.CreateInstance("NumberGuessWorkflowActivities.SequentialNumberGuessWorkflow"))

map.Add(FlowchartNumberGuessIdentity_v1,
    v1Assembly.CreateInstance("NumberGuessWorkflowActivities.FlowchartNumberGuessWorkflow"))

// Add the previous version workflow identities to the dictionary along with
// the corresponding workflow definitions loaded from the v1 assembly.
// Assembly.LoadFile requires an absolute path so convert this relative path
// to an absolute path.
string v1AssemblyPath = @"..\..\..\PreviousVersions\NumberGuessWorkflowActivities_v1.dll";
v1AssemblyPath = Path.GetFullPath(v1AssemblyPath);
Assembly v1Assembly = Assembly.LoadFile(v1AssemblyPath);

map.Add(StateMachineNumberGuessIdentity_v1,
    v1Assembly.CreateInstance("NumberGuessWorkflowActivities.StateMachineNumberGuessWorkflow") as Activity);

map.Add(SequentialNumberGuessIdentity_v1,
    v1Assembly.CreateInstance("NumberGuessWorkflowActivities.SequentialNumberGuessWorkflow") as Activity);

map.Add(FlowchartNumberGuessIdentity_v1,
    v1Assembly.CreateInstance("NumberGuessWorkflowActivities.FlowchartNumberGuessWorkflow") as Activity);

下面的示例完整列出了已更新的 WorkflowVersionMap 类。

Public Module WorkflowVersionMap
    Dim map As Dictionary(Of WorkflowIdentity, Activity)

    'Current version identities.
    Public StateMachineNumberGuessIdentity As WorkflowIdentity
    Public FlowchartNumberGuessIdentity As WorkflowIdentity
    Public SequentialNumberGuessIdentity As WorkflowIdentity

    'v1 Identities.
    Public StateMachineNumberGuessIdentity_v1 As WorkflowIdentity
    Public FlowchartNumberGuessIdentity_v1 As WorkflowIdentity
    Public SequentialNumberGuessIdentity_v1 As WorkflowIdentity

    Sub New()
        map = New Dictionary(Of WorkflowIdentity, Activity)

        'Add the current workflow version identities.
        StateMachineNumberGuessIdentity = New WorkflowIdentity With
        {
            .Name = "StateMachineNumberGuessWorkflow",
            .Version = New Version(2, 0, 0, 0)
        }

        FlowchartNumberGuessIdentity = New WorkflowIdentity With
        {
            .Name = "FlowchartNumberGuessWorkflow",
            .Version = New Version(2, 0, 0, 0)
        }

        SequentialNumberGuessIdentity = New WorkflowIdentity With
        {
            .Name = "SequentialNumberGuessWorkflow",
            .Version = New Version(2, 0, 0, 0)
        }

        map.Add(StateMachineNumberGuessIdentity, New StateMachineNumberGuessWorkflow())
        map.Add(FlowchartNumberGuessIdentity, New FlowchartNumberGuessWorkflow())
        map.Add(SequentialNumberGuessIdentity, New SequentialNumberGuessWorkflow())

        'Initialize the previous workflow version identities.
        StateMachineNumberGuessIdentity_v1 = New WorkflowIdentity With
        {
            .Name = "StateMachineNumberGuessWorkflow",
            .Version = New Version(1, 0, 0, 0)
        }

        FlowchartNumberGuessIdentity_v1 = New WorkflowIdentity With
        {
            .Name = "FlowchartNumberGuessWorkflow",
            .Version = New Version(1, 0, 0, 0)
        }

        SequentialNumberGuessIdentity_v1 = New WorkflowIdentity With
        {
            .Name = "SequentialNumberGuessWorkflow",
            .Version = New Version(1, 0, 0, 0)
        }

        'Add the previous version workflow identities to the dictionary along with
        'the corresponding workflow definitions loaded from the v1 assembly.
        'Assembly.LoadFile requires an absolute path so convert this relative path
        'to an absolute path.
        Dim v1AssemblyPath As String = "..\..\..\PreviousVersions\NumberGuessWorkflowActivities_v1.dll"
        v1AssemblyPath = Path.GetFullPath(v1AssemblyPath)
        Dim v1Assembly As Assembly = Assembly.LoadFile(v1AssemblyPath)

        map.Add(StateMachineNumberGuessIdentity_v1,
            v1Assembly.CreateInstance("NumberGuessWorkflowActivities.StateMachineNumberGuessWorkflow"))

        map.Add(SequentialNumberGuessIdentity_v1,
            v1Assembly.CreateInstance("NumberGuessWorkflowActivities.SequentialNumberGuessWorkflow"))

        map.Add(FlowchartNumberGuessIdentity_v1,
            v1Assembly.CreateInstance("NumberGuessWorkflowActivities.FlowchartNumberGuessWorkflow"))
    End Sub

    Public Function GetWorkflowDefinition(identity As WorkflowIdentity) As Activity
        Return map(identity)
    End Function

    Public Function GetIdentityDescription(identity As WorkflowIdentity) As String
        Return identity.ToString()
    End Function
End Module

public static class WorkflowVersionMap
{
    static Dictionary<WorkflowIdentity, Activity> map;

    // Current version identities.
    static public WorkflowIdentity StateMachineNumberGuessIdentity;
    static public WorkflowIdentity FlowchartNumberGuessIdentity;
    static public WorkflowIdentity SequentialNumberGuessIdentity;

    // v1 identities.
    static public WorkflowIdentity StateMachineNumberGuessIdentity_v1;
    static public WorkflowIdentity FlowchartNumberGuessIdentity_v1;
    static public WorkflowIdentity SequentialNumberGuessIdentity_v1;

    static WorkflowVersionMap()
    {
        map = new Dictionary<WorkflowIdentity, Activity>();

        // Add the current workflow version identities.
        StateMachineNumberGuessIdentity = new WorkflowIdentity
        {
            Name = "StateMachineNumberGuessWorkflow",
            // Version = new Version(1, 0, 0, 0),
            Version = new Version(2, 0, 0, 0)
        };

        FlowchartNumberGuessIdentity = new WorkflowIdentity
        {
            Name = "FlowchartNumberGuessWorkflow",
            // Version = new Version(1, 0, 0, 0),
            Version = new Version(2, 0, 0, 0)
        };

        SequentialNumberGuessIdentity = new WorkflowIdentity
        {
            Name = "SequentialNumberGuessWorkflow",
            // Version = new Version(1, 0, 0, 0),
            Version = new Version(2, 0, 0, 0)
        };

        map.Add(StateMachineNumberGuessIdentity, new StateMachineNumberGuessWorkflow());
        map.Add(FlowchartNumberGuessIdentity, new FlowchartNumberGuessWorkflow());
        map.Add(SequentialNumberGuessIdentity, new SequentialNumberGuessWorkflow());

        // Initialize the previous workflow version identities.
        StateMachineNumberGuessIdentity_v1 = new WorkflowIdentity
        {
            Name = "StateMachineNumberGuessWorkflow",
            Version = new Version(1, 0, 0, 0)
        };

        FlowchartNumberGuessIdentity_v1 = new WorkflowIdentity
        {
            Name = "FlowchartNumberGuessWorkflow",
            Version = new Version(1, 0, 0, 0)
        };

        SequentialNumberGuessIdentity_v1 = new WorkflowIdentity
        {
            Name = "SequentialNumberGuessWorkflow",
            Version = new Version(1, 0, 0, 0)
        };

        // Add the previous version workflow identities to the dictionary along with
        // the corresponding workflow definitions loaded from the v1 assembly.
        // Assembly.LoadFile requires an absolute path so convert this relative path
        // to an absolute path.
        string v1AssemblyPath = @"..\..\..\PreviousVersions\NumberGuessWorkflowActivities_v1.dll";
        v1AssemblyPath = Path.GetFullPath(v1AssemblyPath);
        Assembly v1Assembly = Assembly.LoadFile(v1AssemblyPath);

        map.Add(StateMachineNumberGuessIdentity_v1,
            v1Assembly.CreateInstance("NumberGuessWorkflowActivities.StateMachineNumberGuessWorkflow") as Activity);

        map.Add(SequentialNumberGuessIdentity_v1,
            v1Assembly.CreateInstance("NumberGuessWorkflowActivities.SequentialNumberGuessWorkflow") as Activity);

        map.Add(FlowchartNumberGuessIdentity_v1,
            v1Assembly.CreateInstance("NumberGuessWorkflowActivities.FlowchartNumberGuessWorkflow") as Activity);
    }

    public static Activity GetWorkflowDefinition(WorkflowIdentity identity)
    {
        return map[identity];
    }

    public static string GetIdentityDescription(WorkflowIdentity identity)
    {
        return identity.ToString();
    }
}

生成并运行应用程序

按 Ctrl+Shift+B 以生成应用程序，然后按 Ctrl+F5 启动该应用程序。
通过单击“新游戏”启动新工作流。工作流的版本显示在状态窗口下面，它反映了关联 WorkflowIdentity 的更新版本。请记下 InstanceId，这样您就可以在工作流完成时查看该工作流的跟踪文件，然后在游戏完成之前输入猜测。请注意用户猜测基于 WriteLine 活动的更新在状态窗口中的信息中显示的方式。
```
Please enter a number between 1 and 10
5 is too high.
Please enter a number between 1 and 10
3 is too high.
Please enter a number between 1 and 10
1 is too low.
Please enter a number between 1 and 10
Congratulations, you guessed the number in 4 turns.
```
注意

将显示 WriteLine 活动的更新文本，但不显示已在本主题中添加的最终 WriteLine 活动的输出。这是因为，此状态窗口将由 PersistableIdle 处理程序进行更新。由于该工作流在最终活动之后完成且不会转为空闲状态，因此不会调用 PersistableIdle 处理程序。但是，Completed 处理程序会在状态窗口中显示类似的消息。如果需要，可以向 Completed 处理程序添加代码，以便从 StringWriter 提取文本并在状态窗口中显示。
打开 Windows 资源管理器，导航到“NumberGuessWorkflowHost\bin\debug”文件夹（或“bin\release”，具体取决于项目设置），然后使用记事本打开已完成工作流的对应跟踪文件。如果你未记下 InstanceId，则可以使用 Windows 资源管理器中的“修改日期”信息来识别正确的跟踪文件。
```
Please enter a number between 1 and 10
5 is too high.
Please enter a number between 1 and 10
3 is too high.
Please enter a number between 1 and 10
1 is too low.
Please enter a number between 1 and 10
2 is correct. You guessed it in 4 turns.
```
该跟踪文件中包含已更新的 WriteLine 输出，包括在本主题中添加的 WriteLine 的输出。
切换回数字猜测应用程序，然后选择在进行更新前启动的一个工作流。您可通过查看在状态窗口下面显示的版本信息来识别当前选择的工作流的版本。输入一些猜测，并注意状态更新与前一个版本的 WriteLine 活动输出相符，并且不包括用户猜测。这是因为，这些工作流使用的是不具有 WriteLine 更新的前一个工作流定义。

在下一步如何：更新正在运行的工作流实例的定义中，将更新正在运行的 v1 工作流实例，以便它们包含新功能作为 v2 实例。

如何：并行承载多个版本的工作流

本主题内容

制作 NumberGuessWorkflowActivities 项目的副本

更新工作流

更新 StateMachine 工作流

更新 Flowchart 工作流

更新 Sequential 工作流

更新 WorkflowVersionMap 以包括以前的工作流版本

生成并运行应用程序

反馈

其他资源