WF4.0 基礎篇(二十九) WorkflowInspectionServices

WorkflowInspectionServices 類

WorkflowInspectionServices可以得到流程中的Activity，由於WF4.0的ActivityTree相對復雜,並不是象 WF3.X的結構那樣清晰, 在WF4.0中Activitys,Body,Implementation等了Activity屬性比效多,要循環Activity 就要做很多判斷,這時可以使用WorkflowInspectionServices得到ActivityTree上的所有Activity.

WorkflowInspectionServices可自動判斷Activitys,Body,Implementation等

與自已實現遞歸相比,自已實現遞歸可以操作更多細節,WorkflowInspectionServices則可以快速得到全部 Activity

注意:由於WorkflowInspectionServices只得到Activity,所以流程圖中的

FlowNode

FlowStep

FlowSwitch

FlowDecision

不是從Activity中繼承的,所以WorkflowInspectionServices無法得到這些元素,但這些元素中所包含的 Activity可以得到

靜態方法 GetActivities 基本功能

基於XAML文件名得到Activity：

static Activity getActivity(string filePathName)

{

string valueString = "";

using (System.IO.FileStream fileStream = new System.IO.FileStream(filePathName, System.IO.FileMode.Open, System.IO.FileAccess.Read, System.IO.FileShare.Read))

{

using (System.IO.StreamReader streamReader = new System.IO.StreamReader (fileStream))

{

valueString = streamReader.ReadToEnd();

}

}

System.IO.StringReader stringReader = new System.IO.StringReader(valueString);

Activity activity = System.Activities.XamlIntegration.ActivityXamlServices.Load (stringReader);

WorkflowInspectionServices.CacheMetadata(activity);

return activity;

}

GetActivities方式：

static　void　printActivityTree(Activity　activity,string　tag)
{

Console.WriteLine(tag　+　"{0},type:{1}",　activity.DisplayName,　activity.GetType ());

System.Collections.Generic.IEnumerator<Activity>　list　=　 WorkflowInspectionServices.GetActivities(activity).GetEnumerator();

while　(list.MoveNext())
{
printActivityTree(list.Current,"　"+　tag　);
}
}

遞歸方式：

static　void　printActivityStruce(Activity　activity,　string　tag)
{

System.Console.WriteLine(tag　+　"{0},Type:{1}",　activity.DisplayName,　 activity.GetType());

//如果是表達式　
VisualBasicValue<string>　a　=　activity　as　 VisualBasicValue<string>;

if　(a　!=　null)
{
System.Console.WriteLine(tag　+　a.ExpressionText);
}

//如果是[DynamicActivity]
DynamicActivity　dynamicActivity　=　activity　as　DynamicActivity;
if　(dynamicActivity　!=　null)
{
System.Console.WriteLine(tag　+　"　Properties:");
foreach　(var　item　in　dynamicActivity.Properties)
{
System.Console.WriteLine(tag　+　"　Name:{0},　Type:{1}",　item.Name,　item.Type);
}

System.Console.WriteLine(tag　+　"　Implementation:");

tag　=　tag　+　"　";
printActivityStruce(dynamicActivity.Implementation(),　tag);
}

//如果是[Sequence]
Sequence　sequence　=　activity　as　Sequence;
if　(sequence　!=　null)
{
System.Console.WriteLine(tag　+　"　Variables　:");
foreach　(var　item　in　sequence.Variables)
{
System.Console.WriteLine(tag　+　"　Name:{0},　Type:{1},　Default:{2}",　item.Name,　 item.Type,　item.Default);
}

System.Console.WriteLine(tag　+　"　Activities:");
foreach　(var　item　in　sequence.Activities)
{
tag　=　tag　+　"　";
printActivityStruce(item,　tag);
}
}

}

例子1:Sequence嵌套

static　void　showTestAWorkflow()
{
Activity　wf　=　getActivity("testAWorkflow.xaml");
printActivityTree(wf,　"");

System.Console.WriteLine("=======================");
printActivityStruce(wf,　"");
}

例子2:IF容器

static　void　showTestBWorkflow()
{
Activity　wf　=　getActivity("testBWorkflow.xaml");
printActivityTree(wf,　"");

System.Console.WriteLine("=======================");
printActivityStruce(wf,　"");

}

例子3:FlowChar

static　void　showTestCWorkflow()
{
Activity　wf　=　getActivity("testCWorkflow.xaml");
printActivityTree(wf,　"");

System.Console.WriteLine("=======================");
printActivityStruce(wf,　"");
}

例子4:自定義Activity

static　void　showTestDWorkflow()
{
Activity　wf　=　getActivity("testDWorkflow.xaml");
printActivityTree(wf,　"");

System.Console.WriteLine("=======================");
printActivityStruce(wf,　"");
}

public　sealed　class　muActivity　:　Activity
{
protected　override　Func<Activity>　Implementation
{
get
{
return　getActivity;
}
set
{
base.Implementation　=　value;
}
}

Activity　getActivity()
{
return　new　WriteLine　{　DisplayName　=　"wxwinter"　};
}
}

操作WCF服務中的工作流

xamlx文件中的工作流，可以用XamlServices.Load得到WorkflowService，WorkflowService的Body就對應 WCF服務中的Activity樹

FileStream　fs　=　new　FileStream("Service1.xamlx",　FileMode.Open);
WorkflowService　wfs　=　(WorkflowService)XamlServices.Load(fs);

printActivityTree(wf,"|--");

靜態方法 Resolve

返回流程樹中指定id的Activity

static　void　printActivityID(Activity　activity,　string　tag)
{

Console.WriteLine(tag　+　"{0},{1}",　activity.Id,　activity.DisplayName);

System.Collections.Generic.IEnumerator<Activity>　list　=　 WorkflowInspectionServices.GetActivities(activity).GetEnumerator();

while　(list.MoveNext())
{
printActivityID(list.Current,　"　"　+　tag);
}
}

static　void　findActivityByID()
{
Activity　wf　=　getActivity("testAWorkflow.xaml");
printActivityID(wf,　"");
System.Console.WriteLine("=======================");

Activity　act=　WorkflowInspectionServices.Resolve(wf,　"1.5");
Console.WriteLine("{0},{1}",　act.Id,　act.DisplayName);
}

靜態方法 CacheMetadata

CacheMetadata 方法用於驗證Activity,如果驗證不通過會產生異常,所以應該放入TryCatch中

Activity

public　sealed　class　myActivityA　:　CodeActivity
{

public　InArgument<string>　myText　{　get;　set;　}

protected　override　void　CacheMetadata(CodeActivityMetadata　metadata)
{
myText　=　new　VisualBasicValue<string>　{　ExpressionText　=　"myIn"　};
base.CacheMetadata(metadata);
}

protected　override　void　Execute(CodeActivityContext　context)
{

string　text　=　context.GetValue(this.myText);

System.Console.WriteLine("myActivityA:"　+　text);
}
}

static　void　testCacheMetadata()
{
try
{
System.Console.WriteLine("驗證　myActivityA");
WorkflowInspectionServices.CacheMetadata(new　myActivityA());
System.Console.WriteLine("驗證　myActivityA　通過");
}
catch(System.Exception　ex)
{
System.Console.WriteLine(ex.Message);
}

System.Console.WriteLine ("/====================================================================");

DynamicActivity　dynamicActivity　=　new　DynamicActivity();

dynamicActivity.Properties.Add(new　DynamicActivityProperty
{
Name　=　"myIn",　
Type　=　typeof(InArgument<string>),　
Value　=　new　InArgument<string>()
});

dynamicActivity.Implementation　=()=>new　myActivityA();

try
{
System.Console.WriteLine("驗證　dynamicActivity");
WorkflowInspectionServices.CacheMetadata(dynamicActivity);
System.Console.WriteLine("驗證　dynamicActivity　通ª過");
}
catch　(System.Exception　ex)
{
System.Console.WriteLine(ex.Message);
}
}

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