IIdentifierCreationService.EnsureUniqueIdentifiers 方法

定义

提供一个用于确保添加到 CompositeActivity 中的活动都是唯一命名的活动的机制。

public:
 void EnsureUniqueIdentifiers(System::Workflow::ComponentModel::CompositeActivity ^ parentActivity, System::Collections::ICollection ^ childActivities);
public void EnsureUniqueIdentifiers (System.Workflow.ComponentModel.CompositeActivity parentActivity, System.Collections.ICollection childActivities);
abstract member EnsureUniqueIdentifiers : System.Workflow.ComponentModel.CompositeActivity * System.Collections.ICollection -> unit
Public Sub EnsureUniqueIdentifiers (parentActivity As CompositeActivity, childActivities As ICollection)

参数

parentActivity
CompositeActivity

将包含唯一命名的活动的 CompositeActivity

childActivities
ICollection

一个活动集合,用于确保活动是唯一命名的。

示例

下面的示例演示 IIdentifierCreationService 的实现。 此服务确保当前工作流中使用的每个标识符都是唯一的。

void IIdentifierCreationService.EnsureUniqueIdentifiers(CompositeActivity parentActivity, ICollection childActivities)
{
    if (parentActivity == null)
        throw new ArgumentNullException("parentActivity");
    if (childActivities == null)
        throw new ArgumentNullException("childActivities");

    List<Activity> allActivities = new List<Activity>();

    Queue activities = new Queue(childActivities);
    while (activities.Count > 0)
    {
        Activity activity = (Activity)activities.Dequeue();
        if (activity is CompositeActivity)
        {
            foreach (Activity child in ((CompositeActivity)activity).Activities)
                activities.Enqueue(child);
        }

        //If we are moving activities, we need not regenerate their identifiers
        if (((IComponent)activity).Site != null)
            continue;

        allActivities.Add(activity);
    }

    // get the root activity
    CompositeActivity rootActivity = GetRootActivity(parentActivity) as CompositeActivity;
    ArrayList identifiers = new ArrayList(); // all the identifiers in the workflow
    identifiers.AddRange(GetIdentifiersInCompositeActivity(rootActivity));

    foreach (Activity activity in allActivities)
    {
        string finalIdentifier = activity.Name;

        // now loop until we find a identifier that hasn't been used.
        string baseIdentifier = GetBaseIdentifier(activity);
        int index = 0;

        identifiers.Sort();
        while (finalIdentifier == null || finalIdentifier.Length == 0 || identifiers.BinarySearch(finalIdentifier.ToLower(), StringComparer.OrdinalIgnoreCase) >= 0)
        {
            finalIdentifier = string.Format("{0}{1}", baseIdentifier, ++index);
        }

        // add new identifier to collection
        identifiers.Add(finalIdentifier);
        activity.Name = finalIdentifier;
    }
}

private static IList GetIdentifiersInCompositeActivity(CompositeActivity compositeActivity)
{
    ArrayList identifiers = new ArrayList();
    if (compositeActivity != null)
    {
        identifiers.Add(compositeActivity.Name);
        IList<Activity> allChildren = GetAllNestedActivities(compositeActivity);
        foreach (Activity activity in allChildren)
            identifiers.Add(activity.Name);
    }
    return ArrayList.ReadOnly(identifiers);
}

private static string GetBaseIdentifier(Activity activity)
{
    string baseIdentifier = activity.GetType().Name;
    StringBuilder b = new StringBuilder(baseIdentifier.Length);
    for (int i = 0; i < baseIdentifier.Length; i++)
    {
        if (char.IsUpper(baseIdentifier[i]) && (i == 0 || i == baseIdentifier.Length - 1 || char.IsUpper(baseIdentifier[i + 1])))
        {
            b.Append(char.ToLower(baseIdentifier[i]));
        }
        else
        {
            b.Append(baseIdentifier.Substring(i));
            break;
        }
    }
    return b.ToString();
}

private static Activity GetRootActivity(Activity activity)
{
    if (activity == null)
        throw new ArgumentException("activity");

    while (activity.Parent != null)
        activity = activity.Parent;

    return activity;
}

private static Activity[] GetAllNestedActivities(CompositeActivity compositeActivity)
{
    if (compositeActivity == null)
        throw new ArgumentNullException("compositeActivity");

    ArrayList nestedActivities = new ArrayList();
    Queue compositeActivities = new Queue();
    compositeActivities.Enqueue(compositeActivity);
    while (compositeActivities.Count > 0)
    {
        CompositeActivity compositeActivity2 = (CompositeActivity)compositeActivities.Dequeue();

        foreach (Activity activity in compositeActivity2.Activities)
        {
            nestedActivities.Add(activity);
            if (activity is CompositeActivity)
                compositeActivities.Enqueue(activity);
        }

        foreach (Activity activity in compositeActivity2.EnabledActivities)
        {
            if (!nestedActivities.Contains(activity))
            {
                nestedActivities.Add(activity);
                if (activity is CompositeActivity)
                    compositeActivities.Enqueue(activity);
            }
        }
    }
    return (Activity[])nestedActivities.ToArray(typeof(Activity));
}
Sub EnsureUniqueIdentifiers(ByVal parentActivity As CompositeActivity, ByVal childActivities As ICollection) Implements IIdentifierCreationService.EnsureUniqueIdentifiers

    If parentActivity Is Nothing Then
        Throw New ArgumentNullException("parentActivity")
    End If
    If childActivities Is Nothing Then
        Throw New ArgumentNullException("childActivities")
    End If
    Dim allActivities As New List(Of Activity)()

    Dim activities As New Queue(childActivities)
    While activities.Count > 0

        Dim activity As Activity = CType(activities.Dequeue(), Activity)
        If TypeOf activity Is CompositeActivity Then
            For Each child As Activity In CType(activity, CompositeActivity).Activities
                activities.Enqueue(child)
            Next
        End If

        'If we are moving activities, we need not regenerate their identifiers
        If CType(activity, IComponent).Site IsNot Nothing Then
            Continue While
        End If

        allActivities.Add(activity)
    End While

    ' get the root activity
    Dim rootActivity As CompositeActivity = CType(GetRootActivity(parentActivity), CompositeActivity)
    Dim identifiers As New ArrayList() ' all the identifiers in the workflow
    identifiers.AddRange(GetIdentifiersInCompositeActivity(rootActivity))

    For Each activity As Activity In allActivities

        Dim finalIdentifier As String = activity.Name

        ' now loop until we find a identifier that hasn't been used.
        Dim baseIdentifier As String = GetBaseIdentifier(activity)
        Dim index As Integer = 0

        identifiers.Sort()
        While finalIdentifier Is Nothing Or _
        finalIdentifier.Length = 0 Or _
        identifiers.BinarySearch(finalIdentifier.ToLower(), StringComparer.OrdinalIgnoreCase) >= 0
            finalIdentifier = String.Format("0}1}", baseIdentifier, ++index)
        End While

        ' add new identifier to collection 
        identifiers.Add(finalIdentifier)
        activity.Name = finalIdentifier
    Next
End Sub

Private Shared Function GetIdentifiersInCompositeActivity(ByVal CompositeActivity As CompositeActivity) As IList
    Dim identifiers As New ArrayList()
    If CompositeActivity IsNot Nothing Then
        identifiers.Add(CompositeActivity.Name)
        Dim allChildren As IList(Of Activity) = GetAllNestedActivities(CompositeActivity)
        For Each activity As Activity In allChildren
            identifiers.Add(activity.Name)
        Next
    End If

    Return ArrayList.ReadOnly(identifiers)
End Function

Private Shared Function GetBaseIdentifier(ByVal activity As Activity)
    Dim baseIdentifier As String = activity.GetType().Name
    Dim b As New StringBuilder(baseIdentifier.Length)
    For i As Integer = 0 To baseIdentifier.Length
        If Char.IsUpper(baseIdentifier(i)) And (i = 0 Or i = baseIdentifier.Length - 1 Or Char.IsUpper(baseIdentifier(i + 1))) Then
            b.Append(Char.ToLower(baseIdentifier(i)))
        Else
            b.Append(baseIdentifier.Substring(i))
            Exit For
        End If
    Next
    Return b.ToString()
End Function

Private Shared Function GetRootActivity(ByVal activity As Activity) As Activity
    If activity Is Nothing Then
        Throw New ArgumentException("activity")
    End If

    While activity.Parent IsNot Nothing
        activity = activity.Parent
    End While

    Return activity
End Function

Private Shared Function GetAllNestedActivities(ByVal compositeActivity As CompositeActivity) As Activity()

    If compositeActivity Is Nothing Then
        Throw New ArgumentNullException("compositeActivity")
    End If

    Dim nestedActivities As New ArrayList()
    Dim compositeActivities As New Queue()
    compositeActivities.Enqueue(compositeActivity)
    While compositeActivities.Count > 0

        Dim compositeActivity2 As CompositeActivity = CType(compositeActivities.Dequeue(), CompositeActivity)

        For Each activity As Activity In compositeActivity2.Activities
            nestedActivities.Add(activity)
            If activity Is compositeActivity Then
                compositeActivities.Enqueue(activity)
            End If
        Next

        For Each activity As Activity In compositeActivity2.EnabledActivities
            If Not nestedActivities.Contains(activity) Then
                nestedActivities.Add(activity)
                If (activity Is compositeActivity) Then
                    compositeActivities.Enqueue(activity)
                End If
            End If
        Next
    End While
    Return CType(nestedActivities.ToArray(GetType(Activity)), Activity())

注解

使用 EnsureUniqueIdentifiers 可确保插入 CompositeActivity 中的活动都具有唯一的标识符。

适用于