[转]Using the Interop Activity in a .NET Framework 4 Workflow
本文转自:http://msdn.microsoft.com/en-us/library/ee264174(v=vs.100).aspx
This topic applies to Windows Workflow Foundation 4 (WF4).
Activities created using .NET Framework 3.0 or .NET Framework 3.5 can be used in a .NET Framework 4 workflow by using the Interop activity. This topic provides an overview of using the Interop activity.
![]() |
---|
The Interop activity does not appear in the workflow designer toolbox unless the workflow's project has its Target Framework setting set to .Net Framework 4. |
Using the Interop Activity in .NET Framework 4 Workflows
In this topic, a .NET Framework 3.5 activity library is created that contains a DiscountCalculator
activity. The DiscountCalculator
calculates a discount based on a purchase amount and consists of a SequenceActivity that contains a PolicyActivity.
![]() |
---|
The .NET Framework 3.5 activity created in this topic uses a PolicyActivity to implement the logic of the activity. It is not required to use a custom .NET Framework 3.5 activity or the Interop activity in order to use rules in a .NET Framework 4 workflow. For an example of using rules in a .NET Framework 4 workflow without using the Interop activity, see the Policy Activity in .NET Framework 4 sample. |
To create the .NET Framework 3.5 activity library project
Open Visual Studio 2010 and select New and then Project… from the File menu.
Expand the Other Project Types node in the Installed Templates pane and select Visual Studio Solutions.
Select Blank Solution from the Visual Studio Solutions list. Type PolicyInteropDemo in the Name box and click OK.
Right-click PolicyInteropDemo in Solution Explorer and select Add and then New Project….
Tip:
If the Solution Explorer window is not visible, select Solution Explorer from the View menu. In the Installed Templates list, select Visual C# and then Workflow. Select .NET Framework 3.5 from the .NET Framework version drop-down list, and then select Workflow Activity Library from the Templates list.
Type PolicyActivityLibrary in the Name box and click OK.
Right-click Activity1.cs in Solution Explorer and select Delete. Click OK to confirm.
To create the DiscountCalculator activity
Right-click PolicyActivityLibrary in Solution Explorer and select Add and then Activity….
Select Activity (with code separation) from the Visual C# Items list. Type DiscountCalculator in the Name box and click OK.
Right-click DiscountCalculator.xoml in Solution Explorer and select .
Add the following three properties to the
DiscountCalculator
class.Right-click DiscountCalculator.xoml in Solution Explorer and select View Designer.
Drag a Policy activity from the Windows Workflow v3.0 section of the Toolbox and drop it in the DiscountCalculator activity.
Tip:
If the Toolbox window is not visible, select Toolbox from the View menu.
To configure the rules
Click the newly added Policy activity to select it, if it is not already selected.
Click the RuleSetReference property in the Properties window to select it, and click the ellipsis button to the right of the property.
Tip:
If the Properties window is not visible, choose Properties Window from the View menu. Select Click New….
Click Add Rule.
Type the following expression into the Condition box.
this.Subtotal >= 50 && this.Subtotal < 100
Type the following expression into the Then Actions box.
this.DiscountPercent = 0.075
Click Add Rule.
Type the following expression into the Condition box.
this.Subtotal >= 100
Type the following expression into the Then Actions box.
this.DiscountPercent = 0.15
Click Add Rule.
Type the following expression into the Condition box.
this.DiscountPercent > 0
Type the following expression into the Then Actions box.
this.Total = this.Subtotal - this.Subtotal * this.DiscountPercent
Type the following expression into the Else Actions box.
this.Total = this.Subtotal
Click OK to close the Rule Set Editor dialog box.
Ensure that the newly-created RuleSet is selected in the Name list, and click OK.
Press CTRL+SHIFT+B to build the solution.
The rules added to the DiscountCalculator
activity in this procedure are shown in the following code example.
Rule1: IF this.Subtotal >= 50 && this.Subtotal < 100
THEN this.DiscountPercent = 0.075 Rule2: IF this. Subtotal >= 100
THEN this.DiscountPercent = 0.15 Rule3: IF this.DiscountPercent > 0
THEN this.Total = this.Subtotal - this.Subtotal * this.DiscountPercent
ELSE this.Total = this.Subtotal
When the PolicyActivity executes, these three rules evaluate and modify the Subtotal
, DiscountPercent
, and Total
property values of the DiscountCalculator
activity to calculate the desired discount.
Using the DiscountCalculator Activity with the Interop Activity
To use the DiscountCalculator
activity inside a .NET Framework 4 workflow, the Interop activity is used. In this section two workflows are created, one using code and one using the workflow designer, which show how to use the Interop activity with the DiscountCalculator
activity. The same host application is used for both workflows.
To create the host application
Right-click PolicyInteropDemo in Solution Explorer and select Add, and then New Project….
Ensure that .NET Framework 4 is selected in the .NET Framework version drop-down list, and select Workflow Console Application from the Visual C# Items list.
Type PolicyInteropHost into the Name box and click OK.
Right-click PolicyInteropHost in Solution Explorer and select Properties.
In the Target framework drop-down list, change the selection from .NET Framework 4 Client Profile to .NET Framework 4. Click Yes to confirm.
Right-click PolicyInteropHost in Solution Explorer and select Add Reference….
Select PolicyActivityLibrary from the Projects tab and click OK.
Right-click PolicyInteropHost in Solution Explorer and select Add Reference….
Select System.Workflow.Activities, System.Workflow.ComponentModel, and then System.Workflow.Runtime from the .NET tab and click OK.
Right-click PolicyInteropHost in Solution Explorer and select Set as StartUp Project.
Press CTRL+SHIFT+B to build the solution.
Using the Interop Activity in Code
In this example, a workflow definition is created using code that contains the Interop activity and the DiscountCalculator
activity. This workflow is invoked using WorkflowInvoker and the results of the rule evaluation are written to the console using a WriteLine activity.
To use the Interop activity in code
Right-click Program.cs in Solution Explorer and select .
Add the following
using
statement at the top of the file.Remove the contents of the
Main
method and replace with the following code.Create a new method in the
Program
class calledCalculateDiscountUsingCodeWorkflow
that contains the following code.static void CalculateDiscountUsingCodeWorkflow()
{
Variable<double> Subtotal = new Variable<double>
{
Default = 75.99,
Name = "Subtotal"
}; Variable<double> DiscountPercent = new Variable<double>
{
Name = "DiscountPercent"
}; Variable<double> Total = new Variable<double>
{
Name = "Total"
}; Activity wf = new Sequence
{
Variables = { Subtotal, DiscountPercent, Total },
Activities =
{
new Interop
{
ActivityType = typeof(DiscountCalculator),
ActivityProperties =
{
{ "Subtotal", new InArgument<double>(Subtotal) },
{ "DiscountPercentOut", new OutArgument<double>(DiscountPercent) },
{ "TotalOut", new OutArgument<double>(Total) }
}
},
new WriteLine
{
Text = new InArgument<string>(env =>
string.Format("Subtotal: {0:C}, Discount {1}%, Total {2:C}",
Subtotal.Get(env), DiscountPercent.Get(env) * 100, Total.Get(env)))
}
}
}; WorkflowInvoker.Invoke(wf);
}Note:
The Subtotal
,DiscountPercent
, andTotal
properties of theDiscountCalculator
activity are surfaced as arguments of the Interop activity, and bound to local workflow variables in the Interop activity’s ActivityProperties collection.Subtotal
is added as an In argument because theSubtotal
data flows into the Interop activity, andDiscountPercent
andTotal
are added as Out arguments because their data flows out of the Interop activity. Note that the two Out arguments are added with the namesDiscountPercentOut
andTotalOut
to indicate that they represent Out arguments. TheDiscountCalculator
type is specified as the Interop activity’s ActivityType.Press CTRL+F5 to build and run the application. Substitute different values for the
Subtotal
value to test out the different discount levels provided by theDiscountCalculator
activity.
Using the Interop Activity in the Workflow Designer
In this example, a workflow is created using the workflow designer. This workflow has the same functionality as the previous example, except than instead of using a WriteLine activity to display the discount, the host application retrieves and displays the discount information when the workflow completes. Also, instead of using local workflow variables to contain the data, arguments are created in the workflow designer and the values are passed in from the host when the workflow is invoked.
To host the PolicyActivity using a Workflow Designer-created workflow
Right-click Workflow1.xaml in Solution Explorer and select Delete. Click OK to confirm.
Right-click PolicyInteropHost in Solution Explorer and select Add, New Item….
Expand the Visual C# Items node and select Workflow. Select Activity from the Visual C# Items list.
Type DiscountWorkflow into the Name box and click Add.
Click the Arguments button on the lower left side of the workflow designer to display the Arguments pane.
Click Create Argument.
Type Subtotal into the Name box, select In from the Direction drop-down, select Double from the Argument type drop-down, and then press ENTER to save the argument.
Note:
If Double is not in the Argument type drop-down list, select Browse for Types …, type System.Double in the Type Name box, and click OK. Click Create Argument.
Type DiscountPercent into the Name box, select Out from the Direction drop-down, select Double from the Argument type drop-down, and then press ENTER to save the argument.
Click Create Argument.
Type Total into the Name box, select Out from the Direction drop-down, select Double from the Argument type drop-down, and then press ENTER to save the argument.
Click the Arguments button on the lower left side of the workflow designer to close the Arguments pane.
Drag a Sequence activity from the Control Flow section of the Toolbox and drop it onto the workflow designer surface.
Drag an Interop activity from the Migration section of the Toolbox and drop it in the Sequence activity.
Click the Interop activity on the Click to browse… label, type DiscountCalculator in the Type Name box, and click OK.
Note:
When the Interop activity is added to the workflow and the DiscountCalculator
type is specified as its ActivityType, the Interop activity exposes three In arguments and three Out arguments that represent the three public properties of theDiscountCalculator
activity. The In arguments have the same name as the three public properties, and the three Out arguments have the same names with Out appended to the property name. In the following steps, the workflow arguments created in the previous steps are bound to the Interop activity’s arguments.Type DiscountPercent into the Enter a VB expression box to the right of the DiscountPercentOut property and press TAB.
Type Subtotal into the Enter a VB expression box to the right of the Subtotal property and press TAB.
Type Total into the Enter a VB expression box to the right of the TotalOut property and press TAB.
Right-click Program.cs in Solution Explorer and select .
Add the following
using
statement at the top of the file.Comment out the call to the
CalculateDiscountInCode
method in theMain
method and add the following code.Note:
If you did not follow the previous procedure and the default Main
code is present, replace the contents ofMain
with the following code.Create a new method in the
Program
class calledCalculateDiscountUsingDesignerWorkflow
that contains the following code.static void CalculateDiscountUsingDesignerWorkflow()
{
double SubtotalValue = 125.99;
Dictionary<string, object> wfargs = new Dictionary<string, object>
{
{"Subtotal", SubtotalValue}
}; Activity wf = new DiscountWorkflow(); IDictionary<string, object> outputs =
WorkflowInvoker.Invoke(wf, wfargs); Console.WriteLine("Subtotal: {0:C}, Discount {1}%, Total {2:C}",
SubtotalValue, (double)outputs["DiscountPercent"] * 100,
outputs["Total"]);
}Press CTRL+F5 to build and run the application. To specify a different
Subtotal
amount, change the value ofSubtotalValue
in the following code.
Rules Features Overview
The WF rules engine provides support for processing rules in a priority-based manner with support for forward chaining. Rules can be evaluated for a single item or for items in a collection. For an overview of rules and information on specific rules functionality, please refer to the following table.
Rules Feature | Documentation |
---|---|
Rules Overview |
Introduction to the Windows Workflow Foundation Rules Engine |
RuleSet |
|
Evaluation of Rules |
|
Rules Chaining |
|
Processing Collections in Rules |
|
Using the PolicyActivity |
Workflows created in .NET Framework 4 do not use all of the rules features provided by WF, such as declarative activity conditions and conditional activities such as the ConditionedActivityGroup and ReplicatorActivity. If required, this functionality is available for workflows created using .NET Framework 3.0 and .NET Framework 3.5. For more information, seeMigrating Workflows.
[转]Using the Interop Activity in a .NET Framework 4 Workflow的更多相关文章
- Activity、Task、应用和进程
http://www.cnblogs.com/franksunny/archive/2012/04/17/2453403.html Activity.Task.应用和进程 为了阅读方便,将文档转成pd ...
- VS2012 开发SharePoint 2013 声明式workflow action(activity)之 HelloWorld
本文讲述VS2012 开发SharePoint 2013 声明式workflow action 之 HelloWorld. 使用VS2012开发客户化的workflow action是SharePoi ...
- activity 工作流学习(一)
一.了解工作流 1.工作流(Workflow),就是“业务过程的部分或整体在计算机应用环境下的自动化”,它主要解决的是“使在多个参与者之间按照某种预定义的规则传递文档.信息或任务的过程自动进行,从而实 ...
- Sharepoint学习笔记—习题系列--70-576习题解析 -(Q141-Q143)
Question 141 You are planning an upgrade to a SharePoint 2010 application. You have the following r ...
- EF 5 最佳实践白皮书
Performance Considerations for Entity Framework 5 By David Obando, Eric Dettinger and others Publish ...
- Software Engineering: 3. Project planning
recourse: "Software Engineering", Ian Sommerville Keywords for this chapter: planning sche ...
- android实现qq邮箱多个图标效果
前几天,蛋疼的技术主管非要实现类似装一个qq邮箱,然后能够使用qq邮箱日历的那么一个东西.相当于一个应用生成两个图标,可是不同的是点击不同的图标能够进入不同的应用,例如以下图的效果. 这效果百度了一天 ...
- Contoso 大学 - 10 - 高级 EF 应用场景
原文 Contoso 大学 - 10 - 高级 EF 应用场景 By Tom Dykstra, Tom Dykstra is a Senior Programming Writer on Micros ...
- Unity 接MM横屏闪退的原因
=.=研究了1天接SDK到处都在报错,于是使用logcat查看原因截取到这样的Exception. call to OpenGL ES API withno current context(logge ...
随机推荐
- java.lang.ClassCastException: $Proxy0 cannot be cast to javax.servlet.ServletRequestWrapper
我是在myeclipse 8.5使用代理的时候遇到这个问题的.因为我是跟着视频敲的,所以按道理代码是不会有问题..最后经过我百折不挠的折腾,我发现问题的根源 是 myeclipse自带的tomcat. ...
- 解决GitHub加载和下载慢问题
1. 修改HOSTS文件: 在“C:\Windows\System32\drivers\etc” 下的HOSTS文件,添加以下地址: 151.101.44.249 github.global.ss ...
- shell脚本常用(记)
1.变量检查,判空 a.直接变量判断 if [ ! $1 ];then ..empty..fi b.变量通过" "引号引起来 if [ ! -n "$1" ...
- 文件上传Apache
Map<String, Object> rtnMap = new HashMap<String, Object>(); // 获取文件 String tempPath = re ...
- YTU 2558: 游起来吧!超妹!
2558: 游起来吧!超妹! 时间限制: 1 Sec 内存限制: 128 MB 提交: 70 解决: 22 题目描述 夏天到了,无聊的超妹跑到了落雪湖里抓鱼吃.结果,游到湖的正中 央时被湖边保安看 ...
- BZOJ_2819_Nim_树状数组维护出栈入栈序
BZOJ_2819_Nim_树状数组维护出栈入栈序 Description 著名游戏设计师vfleaking,最近迷上了Nim.普通的Nim游戏为:两个人进行游戏,N堆石子,每回合可以取其中某一堆的任 ...
- [OS][FS]查看ext3文件系统分区的superblock
本文将介绍怎样读取一个分区的superblock: 1. 首先我们查看一下在磁盘上有哪些分区,通过fdisk -l 这里有三个分区,我们下面查看/dev/sda3(这是一个device file) 2 ...
- 使用反射机制恢复xml文件表示的对象
完成如下功能:1)有一个(任意)对象,里面有N个properties以及getter和setter方法2)有一个properties文件,有N个key,value来描述对象中property的值3)有 ...
- [转]响应式web设计之CSS3 Media Queries
开始研究响应式web设计,CSS3 Media Queries是入门. Media Queries,其作用就是允许添加表达式用以确定媒体的环境情况,以此来应用不同的样式表.换句话说,其允许我们在不改变 ...
- 关于XAMPP Apache无法启动问题解决方案
安装好XAMPP后,启动Apache服务启动失败,然后从xampp安装目录下执行apache_start.bat文件,如下图 显示443端口被占用. 解决方法: 启动cmd,输入netstat -a ...