While 构造函数

定义

命名空间:

System.Activities.Statements

程序集:

System.Activities.dll

创建 While 活动的新实例。

重载

While()	创建 While 活动的新实例。
While(Activity<Boolean>)	创建 While 活动的新实例。
While(Expression<Func<ActivityContext,Boolean>>)	创建 While 活动的新实例。

示例

下面的代码示例演示如何创建 While 活动。

new While
{
    Condition = true,
    Body = new Receive
    {
        ServiceContractName = Constants.POContractName,
        OperationName = Constants.UpdatePOName,
        CorrelatesWith = poidHandle, // identifies that the UpdatePO operation is waiting on the PurchaseOrderId that was used to initialize this handle
        CorrelatesOn = new MessageQuerySet // the query that is used on an incoming message to find the requisite PurchaseOrderId specified in the correlation
        {
            // Id is the name of the incoming parameter within the PurchaseOrder
            { "PoId", new XPathMessageQuery("sm:body()/defns:PurchaseOrder/defns:Id", Constants.XPathMessageContext) }
        },
        Content = ReceiveContent.Create(new OutArgument<PurchaseOrder>(po)) // creates a ReceiveMessageContent
    }
},

While()

创建 While 活动的新实例。

public:
 While();

public While ();

Public Sub New ()

示例

下面的代码示例演示如何创建 While 活动。

new While
{
    Condition = true,
    Body = new Receive
    {
        ServiceContractName = Constants.POContractName,
        OperationName = Constants.UpdatePOName,
        CorrelatesWith = poidHandle, // identifies that the UpdatePO operation is waiting on the PurchaseOrderId that was used to initialize this handle
        CorrelatesOn = new MessageQuerySet // the query that is used on an incoming message to find the requisite PurchaseOrderId specified in the correlation
        {
            // Id is the name of the incoming parameter within the PurchaseOrder
            { "PoId", new XPathMessageQuery("sm:body()/defns:PurchaseOrder/defns:Id", Constants.XPathMessageContext) }
        },
        Content = ReceiveContent.Create(new OutArgument<PurchaseOrder>(po)) // creates a ReceiveMessageContent
    }
},

While(Activity<Boolean>)

创建 While 活动的新实例。

public:
 While(System::Activities::Activity<bool> ^ condition);

public While (System.Activities.Activity<bool> condition);

new System.Activities.Statements.While : System.Activities.Activity<bool> -> System.Activities.Statements.While

Public Sub New (condition As Activity(Of Boolean))

参数

condition

Activity<Boolean>

活动依据其进行迭代的条件。

While(Expression<Func<ActivityContext,Boolean>>)

创建 While 活动的新实例。

public:
 While(System::Linq::Expressions::Expression<Func<System::Activities::ActivityContext ^, bool> ^> ^ condition);

public While (System.Linq.Expressions.Expression<Func<System.Activities.ActivityContext,bool>> condition);

new System.Activities.Statements.While : System.Linq.Expressions.Expression<Func<System.Activities.ActivityContext, bool>> -> System.Activities.Statements.While

Public Sub New (condition As Expression(Of Func(Of ActivityContext, Boolean)))

参数

condition

Expression<Func<ActivityContext,Boolean>>

活动依据其进行迭代的条件。