IParametersInProvider.NoParametersIn 事件

请注意：此 API 现在已过时。

没有可用于发送到使用者 Web 部件的参数列表时，发生此事件。

命名空间：  Microsoft.SharePoint.WebPartPages.Communication
程序集：  Microsoft.SharePoint（位于 Microsoft.SharePoint.dll 中）

语法

声明
<ObsoleteAttribute("Use System.Web.UI.WebControls.WebParts.IWebPartParameters instead")> _
Event NoParametersIn As NoParametersInEventHandler
用法
Dim instance As IParametersInProvider
Dim handler As NoParametersInEventHandler

AddHandler instance.NoParametersIn, handler

[ObsoleteAttribute("Use System.Web.UI.WebControls.WebParts.IWebPartParameters instead")]
event NoParametersInEventHandler NoParametersIn

备注

ParametersInReady或NoParametersIn事件，应始终会引发实现IParametersInProvider接口的 Web 部件。如果没有收到此信息，某些 Web 部件可能不能正常工作。引发ParametersInReady事件发送参数。引发NoParametersIn事件，以指示不由参数中的任何更改。

示例

下面的代码示例演示将触发NoParametersIn事件重写的PartCommunicationMain方法。此代码示例是示例的一个更大提供的IParametersInProvider接口的一部分。

      Public Overrides Sub PartCommunicationMain()
            ' Ensure that all of the Web Part's controls are created.
            EnsureChildControls()

            'Check if connected
            If _connected Then
                ' Create the ParametersInReadyEventArgs object for the ParametersInReady event.
                Dim parametersInReadyEventArgs As New ParametersInReadyEventArgs()

                If _parametersReadyButtonClicked Then 'ParametersInReady Button was clicked

                    ' Set the parameter values to the text box values.
                    If Not (_fieldList Is Nothing) Then
                        parametersInReadyEventArgs.ParameterValues = New String(_fieldList.Length) {}

                        Dim index As Integer
                        For index = 0 To _fieldList.Length - 1
                            parametersInReadyEventArgs.ParameterValues(index) = _fontAttributeTextBox(index).Text
                        Next index

                        ' Fire the ParametersInReady event.
                        RaiseEvent ParametersInReady(Me, parametersInReadyEventArgs)
                        '_fieldList is null
                    Else
                        ' Fire the event.
                        RaiseEvent NoParametersIn(Me, New EventArgs())
                    End If
                    _parametersReadyButtonClicked = False
                ElseIf _noParametersInButtonClicked Then 'NoParametersIn Button was clicked                       
                    ' Fire the NoParametersIn event.
                    RaiseEvent NoParametersIn(Me, New EventArgs())
                    _noParametersInButtonClicked = False
                End If
            End If
        End Sub

// Step #7: Implement the PartCommunicationMain() method.
// The PartCommunicationMain method is called by the Web Part 
// infrastructure on the client during the ASP.NET PreRender
// event to allow the part to pass its primary data to the other 
// connected parts.
// It is important to always fire either the ParametersInReady or the 
// NoParametersIn event. Some parts
// may not behave properly if they are left waiting for this 
// information.
// ParametersInReady should be fired to send the parameters.
// NoParametersIn should be fired to indicate that there is no change 
// in the parameters.
public override void PartCommunicationMain()
{
    // Ensure that all of the Web Part's controls are created.
    EnsureChildControls();

    //Check if connected
    if(_connected)
    {
        // If there is a listener, fire the ParametersInReady event.
        if(ParametersInReady != null)
        {
            // Create the ParametersInReadyEventArgs object for the ParametersInReady event.
            ParametersInReadyEventArgs parametersInReadyEventArgs = new ParametersInReadyEventArgs();

            if(_parametersReadyButtonClicked) //ParametersInReady Button was clicked
            {
                // If there is a listener, fire the ParametersInReady 
                // event.
                if(ParametersInReady != null)
                {
                    // Set the parameter values to the text box values.
                    if (_fieldList != null)
                    {
                        parametersInReadyEventArgs.ParameterValues = new string[_fieldList.Length];

                        for (int index = 0; index < _fieldList.Length; index++)
                        {
                            parametersInReadyEventArgs.ParameterValues[index] = _fontAttributeTextBox[index].Text;
                        }

                        // Fire the ParametersInReady event.
                        ParametersInReady(this, parametersInReadyEventArgs);
                    }
                    else //_fieldList is null
                    {
                        // If there is a listener, fire the NoParametersIn event.
                        if(NoParametersIn != null)
                        {
                            // Fire the event.
                            NoParametersIn(this, new EventArgs());
                        }
                    }
                    _parametersReadyButtonClicked = false;
                }
            }
            else if(_noParametersInButtonClicked) //NoParametersIn Button was clicked
            {
                // If there is a listener, fire the NoParametersIn 
                // event.
                if(NoParametersIn != null)
                {
                    // Fire the NoParametersIn event.
                    NoParametersIn(this, new EventArgs());

                    _noParametersInButtonClicked = false;
                }
            }
        }
    }
}

另请参阅

引用

IParametersInProvider 接口

IParametersInProvider 成员

Microsoft.SharePoint.WebPartPages.Communication 命名空间